This PDF file contains the front matter associated with SPIE Proceedings Volume 7658, including the Title Page, Copyright information, Table of Contents, Introduction, and the Conference Committee listing.

Silicon thin-films are fabricated on quartz substrates in the substrate temperature range 500~600 °C by electron-beam evaporation (EBE). Scanning Electron Microscopy (SEM) is employed to characterize the surface morphology of the films and measure the grain size. It is found that, there is an optimum temperature for getting large grain size. The X-ray diffraction (XRD) results show that the preferred crystallographic orientation on quartz wafer is (111). Raman spectra demonstrate the crystallization condition of the films and the crystalline volume fraction are calculated. The results indicate that the growth characteristics of the films depend significantly on the substrate temperature. Silicon thin-films are observed to be amorphous under the temperature of 560 °; above this temperature, they are polycrystalline. In other words, 560 °C is the critical temperature of the films transforming from amorphous silicon to poly-Si. The optimum temperature at about 580 ° for the growth of the film on quartz substrates is obtained. The films exhibit the largest grain size, highest value of crystalline volume fraction and the best structural quality when the substrate is kept at this temperature.

The difficulty for no-reference image quality assessment is the lack of the information of the reference image. With the analysis of the mathematical model of the photoelectric imaging system and the reason for image blur, a method is proposed for constructing reference images, and at the same time the Structural Similarity index is introduced into noreference image quality assessment. A novel no-reference image quality assessment index called No-Reference Structural Sharpness is then proposed for quality evaluation of blurred images. This method constructs a reference image by a low-pass filter, and assesses the image quality by computing the structural similarity index between the original image and the reference one, thus considering the mathematical model of imaging system as well as the advantages of Structural Similarity index. The experimental results show that the new index is well in accordance with quality assessment results of both subjective evaluation and full-reference methods.

Photoluminescence (PL) and photovoltaic (PV) performance of poly3-octylthiophene (P3OT) and poly3-alkylthiophene (P3DT) were studied in detailed. The two kinds of polymer can exhibit strong deep red emission peaking at 688 nm for P3OT and 675 nm for P3DT under blue light excitation, the effective excitation wavelength is about 462 nm. The dynamic process of exciton induced by light excitation strongly determined the PL and PV characteristics. From the PL excitation spectra of P3OT and P3DT, it can be seen that there are wide and intense excitation wavelengths in the visible light range. Two kinds of polymer solar cells based on P3OT or P3DT doping with PCBM were fabricated and the characteristics of OPVs were measured, the short current density (Jsc) and open circuit voltage (Voc) are 0.84 mA/cm², 0.95 mA/cm² and 180 mV, 270 mV, respectively.

Optical Wireless Communication (OWC) adopts laser beam as the carrier to deliver the message. It combines with the advantages of Microwave Communication and Fiber Optic Communication. The key technologies of OWC system includes source coding, channel coding, laser diode modulation, auto-alignment and channel. In this paper, the research progress on OWC in Xi'an University of Technology is introduced. The research on source coding involves in baseband modulation, frequency modulation, OFDM transmission and vertical layered space-time codes. The research on channel coding includes RS codes, Turbo codes, LDPC codes and so on. And the adaptive coding method is analyzed to meet the different channel characteristics. Propagation performance of laser is studied and bit error rate (BER) is measured under various weather conditions of rainy days, snowy days, foggy days, hazy days and so on. The experiment results show that applying channel coding methods can improve the system performance of OWC, especially under rainy, snowy, foggy weather conditions, the BER after decoding is up to 10^-6. Based on many years of research, the technologies of MIMO, OFDM and space-time coding are proved to be the key technologies that need to solve in OWC.

The energy band of red light-emitting materials is usually very narrow, which easily results in non-radiative recombination of excited states. There also exists concentration quenching effect due to strong π-π interaction. To avoid this, host-guest doping system is mostly used. On the other hand, the ratio of singlet and triplet excited state caused by recombination is 1:3. In comparison with the fluorescence (singlet to singlet), phosphorescence (triplet to singlet, but spin-forbidden) is much weaker, and the quantum yield is much lower. To enhance it and make full use of triplet excited state energy, heavy atom effect is commonly used to induce strong spin-orbital coupling leading to mix of singlet and triplet and release the forbidden triplet energy. Based on this, we fabricated polymer light-emitting diodes adopting polyvinylcarbazole (PVK) as the host and a red fluorescent dye, 2-{2-methyl-6-[2-(2,3,6,7-tetrahydro-1H,5H-pyrido[ 3,2,1-ij]quinolin-9-yl)-vinyl]-pyran-4-ylidene}-alononitrile (DCM2), as the dopant, and materials containing heavy-ion, kalium idode (KI) and bromo-carbazole, as energy transfer bridge to obtain complete energy transfer from excited states of both singlet and triplet energy level of PVK to ground state of singlet of DCM2. We found the current density of devices with heavy-ion materials were higher than device without it, and the weak blue emission from PVK host, existing in device of PVK:DCM2 device, can not be observed in electroluminescence spectra of device with heavy-ion materials, which indicates a complete energy transfer from both triplet and singlet energy levels.

Surface acoustic wave (SAW) devices have been widely used for various chemical sensing applications because the sensor signal can be detected by simple and inexpensive electronics. The interactions between target analyte and the sensor surface cause changes in the mechanical, electrical, dielectric properties of the sensing coating deposited onto acoustic transducer. The changes in these properties will lead to changes in the velocity and amplitude of wave modes, which can be measured by frequency and insertion loss (IL) changes when the acoustic element is realized as a delay line or resonator. Among the different sensing coatings, the supermolecules are of considerable interest because the host molecules can be thought as original receptors allowing a specific recognition of guest molecules based on "key-lock" system. In this paper, SAW ethanol gas sensors that utilize the supermolecule of cryptophane-A as sensitive layer have been studied. We synthesized cryptophane-A from vanillyl alcohol using a double trimerisation method and deposited it on the SAW devices to fabricate cryptophane-A based SAW gas sensors. The SAW frequency and insertion loss (IL) were measured using a network analyzer. The frequency shift as the response of the cryptophane-A based SAW sensors to different concentration ethanol was measured at room temperature. It is found that the cryptophane-A based SAW sensor has high sensitivity and good reproductivity to ethanol. The frequency response increased linearly with the concentration of the ethanol.

Ag monodoped, N monodoped and (nN, Ag) codoped ZnO have been investigated by the first-principles calculations, where the formation energies and ionization energies of various complexes and the electronic structure for 3N-Ag complex are studied. The calculated results are that N prefers to substitute O site, and Ag substitutes Zn site under the most growth condition, which indicate NO and AgZn all act as acceptors. Meanwhile, it's shown that N-Ag, 2N-Ag complex contribute little to p-type conduction because of the relatively higher ionization energy. However, 3N-Ag complex may have the lowest ionization energy among various complexes, while the formation energy of 3N-Ag is lower than that of N monodoped, Ag monodoped, N-Ag and 2N-Ag complex under the Zn-rich condition, which indicates that 3N-Ag complex is energetically favorable for the formation of p-type ZnO. Furthermore, by studying the electronic structure of 3N-Ag complex, it may generate an additional impurity band above the valence band maximum of ZnO. It is found that NO generated holes around the top of the valence band, and at the same time, N 2p states hybridized with 4d states of AgZn at the Fermi energy, and the hybridization lowered the repulsive interaction between the two dual acceptors, which enhance the concentration of impurities and the stability of the system, indicating that the dual acceptors evidently improve p-type conductivity of ZnO. Thus, it is found that 3N-Ag complex is the better dopant configuration. That can gain a better quality p-type ZnO under the Zn-rich condition. Our theoretical results are consistent with the experiment results.

In this work, vanadium oxide thin films were grown on glass slides by using reactive direct current (DC) magnetron sputtering from a vanadium target in an Ar+O₂ atmosphere. It was found that the surface morphology, electrical and optical properties were strongly affected by the deposition temperature. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used to characterize the structure and surface morphology of the samples. The structures of these films showed amorphous nature according to the XRD patterns showing no sharp diffraction peak. Measurements of SEM indicated the smooth surface of film deposited at low deposition temperature and rough surface at relatively high deposition temperature. In addition, these surfaces showed no obvious crystalline morphologies, which supported the XRD results. Electrical measurement indicated that the square resistances of films showed an exponential increase from 33 kΩ/square to 46 MΩ/square as the deposition temperature decreased from 320 to 160 °C, and that the square resistancetemperature curves of films exhibited typical semiconducting behavior. The investigation of optical properties of films in near-infrared range indicated that transmittance varied from about 95 % to 55 % when the deposition temperature elevated. In the ultraviolet-visible range, optical transmission measurements revealed that films showed distinguished transmission spectra when they were grown at different deposition temperatures. In the range of 300 to 400 nm, a transmittance shoulder was observed in the spectra, and this shoulder enhanced when the deposition temperature increased. On the other hand, a transmission enhancement at 530 nm disappeared after the deposition temperature exceeded 240 °C.

Using reactive radio-frequency magnetron sputtering technique, ZnO films are grown on Si (111) substrates with ZnO buffer layers deposited under different temperature with optimal condition of working pressure, sputtering power, flux of gas and sputtering time. In order to study the influence of ZnO buffer depositing temperature on the characteristic of the ZnO film, atomic force microscope, X ray diffraction, Raman spectroscopy and photoluminescence spectrum are used to analyze the morphology, growth orientation, Raman spectrum and optical properties of the ZnO films. It is concluded that the optimal depositing temperature of the ZnO buffer for the growth of the top ZnO film is 350 °C.

In this paper, the high temperature solid state reaction method was applied to the preparation of SrTiO₃ ceramic target. The phase of the target has been researched in experiment by X-ray diffraction (XRD). We found that solid state reaction has achieved completely. Then SrTiO₃ thin films on MgO (100) substrate were manufactured by PLD using the triple-frequency harmonics of pulsed laser Nd: YAG. The thickness of the SrTiO₃ thin films was measured using a stylus profiler. Their microstructure and surface morphology were analyzed using X-ray diffraction (XRD) and atomic force microscopy (AFM). Their optical character was characterized using optical transmission spectrum. Additionally, X-ray photoelectron spectroscopy (XPS) spectra were used to characterize the surface chemical composition of the SrTiO₃ thin film. In accordance with the above text result, the relation between the substrate temperature and the SrTiO₃ thin films' the structure and character was analyzed and discussed. With increasing temperature of the substrate, film grain size gradually increased and then smaller. The optimized substrate temperature was found to be 700 °C at which the STO films' structure could uniformly dense. The STO films present a low optical absorption in the 400~1000nm wavelength range, and the substrate temperature is not the main reason for the impact of the optical absorption. The optical band gap energy was found to be about 3.5 ~ 4.0eV for the STO thin film. The valences of the three elements (Sr, Ti, and O) in the STO film prepared by PLD are 2+, 4+ and 2-, respectively.

A numerical model of multilayer organic light-emitting devices (OLED) is presented in this paper which was consisted of electrical and optical model. The electrical model is based on the drift-diffusion equations. Multilayer organic heterojunctions were mostly considered in this work. A simulation course was programmed with MATLAB. The I-V characteristics obtained show a good agreement with experiment data. The optical model utilizes the optical interface effect, the EL spectrum was calculated with Alq₃ thickness of 40 nm, 50 nm and 60 nm, respectively. The Brightness- Voltage characteristics was simulated, the results and experimental data in the literature are in good agreement on the magnitude.

The pyramid-like texture ZnO thin films were usually synthesized by MOCVD or etching the as-prepared RF magnetron sputtering films, and the expensive equipment cost and uncontrollable acid etching, respectively are two main disadvantages both the MOCVD and RF magnetron sputtered. In this paper, the pyramid-like texture ZnO thin films were prepared through a low-cost two-step process, firstly, a seed ZnO:Al layer was coated on the quartz substrates by sol-gel method and subsequently a ZnO thin film was fabricated by RF magnetron sputtered. It is shown from the XRD and SEM results that the ZnO thin film has (101) preferential orientation with a pyramid-like texture. According to the measurement results of ZnO films' resistivity and UV-Visible transmission spectra, the lower resistivity of 10^-3 Ω•cm and optical transmission of higher than 80 % were obtained for these ZnO films. It has shown that the pyramid-like ZnO thin film is a potential transparent conductive film used in amorphous silicon solar cell for front electrode, and the cell performance is comparable advantages for that of ITO conductive film.

In this paper, the effects of substrate temperature during film growth at relative high temperature have been reported. The IGZO thin films were fabricated by means of pulse laser deposition (PLD) with the InGaZnO (In₂O₃: Ga₂O₃: ZnO=1: 1: 8 mol %) target. The substrate temperature altered from room temperature (RT) to 800 °C. The product thin films were characterized rigorously by X-ray diffraction (XRD), atomic force microscopy (AFM), UV-VIS spectrometer, Halleffect investigation and X-ray photoelectron spectroscopy (XPS). The IGZO films was with smooth surface, high transmission in the visible spectral range (about 75-92 %), carrier mobility > 8.0 cm²/(V·s) and carrier concentration at about 10¹⁸ cm^-3. Finally, the character changes influenced by temperature were obtained from analysis results. This task may benefit to a flat panel display in the process of thin film transistors(TFT) fabrications and improvements.

Polymers are emerging as an important material in the field of integrated optics. In this paper, we propose a simple method to fabricate polymer waveguides by using a novel polymer PSQ-L. The high index polymer PSQ-LH is used as a core material and the low index polymer PSQ-LL is used as a cladding material. The waveguide circuits are replicated by using a UV-based soft lithography process. Unlike in conventional imprint processes, the imprint step for structuring is done first on the cladding layer rather than on the core layer and is followed by a spin-coating step to fill the imprinted features with core layer material. The all-polymer microring resonators are fabricated by this method. The coupling efficiency between the straight waveguides and the ring is adjusted by controlling the gap distance between the straight waveguides and the ring. About 20dB extinction ratio and a high Q factor of 3.4×10⁴ is obtained for critically coupled PSQ-L ring resonator.

Balanced charge carrier and appropriate exciton confinement are considered as the key factors for the realization of highly efficient and stable organic light-emitting devices (OLEDs). An effective way to reach a loss free hole-electron recombination and exciton leakage is to use suitable electron transporting layers (ETLs). To investigate the influence of triplet energy and electron transporting properties of ETLs on the performance of iridium complex yellow phosphorescent OLEDs, we fabricated three devices based on bis[2-(4-tert-butylphenyl)benzothiazolato-N,C2']iridium (acetylacetonate) [(t-bt)2Ir(acac)] doped 4,4'-bis(carbazol-9-yl) biphenyl (CBP) host by using 2,9-dimethyl-4,7-diphenyl- 1,10-phenanthroline (BCP), 1,3,5-tris(N-phenylbenzimidazole-2-yl)benzene (TPBi), and 4,7-diphyenyl-1,10- phenanthroline (BPhen) as ETLs, respectively. It was found that there was no apparent correlation between the device efficiency and the triplet energy of ETLs. Instead, device efficiency was determined by the electron mobility of ETLs only. With an optimized device using BPhen as ETL, a power efficiency of 23.1 lm/W and a current efficiency of 28.0 cd/A at 0.08 mA/cm² were achieved, which was much higher than that of the control devices (7.5 lm/W for BCP-device and 8.5 lm/W for TPBi-device). The improved efficiency was attributed to that BPhen had the highest electron mobility and provided better charge balance in the hole-dominant devices. Moreover, the EL spectra of three devices showed no obvious difference with a light emission from iridium complex peaked at 562 nm and a shoulder peak at 600 nm. This indicated that no matter BCP, TPBi or BPhen acted as ETLs, the (t-bt)₂Ir(acac) triplet exciton can be confined within the emissive layer effectively.

The controllable preparation of platinum nanoparticles with defined shapes, including sphere, octahedron, octapods and tetrapods, was realized by varying the concentration of NaNO₃ in the solvothermal process. NaNO3 plays a critical role in synthesizing Pt nanoparticles with different shapes. These Pt nanoparticles were self-assembled on glass substrates to study the influence of metal nanoparticles' shape on their SERS enhancement using 4-mercaptopyridine as molecules probes. Thanks to the enhanced local field effect around their sharp corners and edges, those Pt tetrapods exhibit enhanced SERS properties than those particles with other shapes.

A novel proposal for phase locking based on cubic susceptibility medium has been theoretically proposed and experimentally demonstrated. The expression for phase difference between injected waves is yielded from the coupled wave equations, which implies the phase noise can be eliminated through low-efficiency four-wave mixing (FWM). Beat-note signal and autocorrelation trace heterodyned by the injected waves with small and large detune are adopted to assess phase locking effect, and they are monitored by electrical spectrum analyzer (ESA) and autocorrelator (AC) respectively. Moreover, the influence of polarization state on phase locking is also investigated, and experimental results match well with the theoretical predictions.

Efficient organic photovoltaic cells based on a phosphor of (t-bt)₂Ir(acac) were demonstrated. Also, the photovoltaic performances of organic solar cells with a device structure of ITO/(t-bt)₂Ir(acac):CuPc (doping rate R=0 and 0.25)/C₆₀/BCP/Ag were determined based on the current density (J)-voltage (V) curves of a series of devices. The absorption spectra of doping layer (t-bt)₂Ir(acac):CuPc and C₆₀ films on quart substrates were measured to gain a direct insight of absorption ability of dopant (t-bt)₂Ir(acac). Then, revised optical transfer matrix theory was adopted to study inner effect of dopant (t-bt)₂Ir(acac) on the enhanced device performance, which shows that (t-bt)₂Ir(acac) dopant increases the light density of doping layer by reorganizing the light distribution inside organic films. However, the light absorption efficiency η_A of device with R=0.25 does not improve. According to the unchanging value of open circuit voltage V_OC and similar fill factor FF, the assumption that two devices with R=0 and 0.25 possess similar charge carrier collection efficiency ηCTηCC can be made. Thus, the inner enhancement of exciton diffusion efficiency η_ED is discovered with the assistance of longer triplet exciton diffusion length of (t-bt)₂Ir(acac).

The film thickness and the composition of the fiber can be controlled by ALD (Atomic Layer Deposition) process at atomic level. Therefore, a special fiber with the structure of alternating deposition of doped Nano-semiconductor materials (such as PbS, InP etc.) and SiO2 can be manufactured by ALD process. In a word, this would not only change the manufacturing technology of fiber, but also greatly changed the structure of fiber. In this paper the Band-gap energy and absorption wavelength is calculated for different nano-particle size by the influence of Quantum Size Effect. Considering the 1550 nm wavelength used widely in optical communication, the particle size is calculated, which is used in a simulated structure of the special fiber. Then Based on the simulation of the distribution of optical field, we draw a conclusion that the light field intensity in the special fiber is lower than the single fiber. Therefore, a high-power pumping light should be added if the special fiber is used as amplifying fiber.

Single-photon detector based on an InGaAs avalanche photodiode is one of hot research on the quantum photon, and is one of the key technologies on quantum communication and quantum image. It is widely used in applications as high sensitive photon spectrum, high speed optic measurement and so on. A suitable delay and comparator with latch function circuit are used to prevent positive and negative transient pulses from influencing the detection of true photon induced avalanches. A dead time modulation feedback control circuit decreases the after-pulse. Especially, ECL difference circuit is the key of high speed single photon detector. In addition, the detector uses the hot tube fan-cooling method. From the performance test, the lowest temperature reaches -62°C, the minimum gate pulse width is 2ns (Full-Width-Half-Max, FWHM) and the dark counter rate is 2.5×10^-6 ns^-1 with a detection rate of 10MHz when the quantum efficiency is more than 10%.

Images of scenes acquired in bad weather have poor contrasts and colors. In this paper, we exploit the idea of interactive method and recover the images based on physical model. First, a simple method is proposed to estimate the scene depths. Second, the parameters in the depths model can be obtained automatically from a single image. Experiments show that our method can remove the haze effectively. Especially, it is easy to serve for the practice.

In practical application of Liquid crystal optical phased array (LCOPA) device, diffraction efficiency and deflection range are two important performance parameters, which should be improved further more. Both diffraction efficiency and deflection range are directly related to the width of flyback region. Therefore, the flyback region problem was analyzed quantitatively in this paper. According to elastic continuum theory of liquid crystal and crystal optics theory, we calculated LC director and its phase delay profile. Then we analyzed quantitatively the influence of device parameters including electrode size, alignment layer thickness and LC cell thickness on the width of flyback region. Results show that there exists a critical value of electrode size. When electrode size is larger than this critical value, the width of flyback region increases nearly linear to the increase of electrode size. The width of flyback region is not sensitive to alignment layer thickness and increases monotonously with the increase of LC cell thickness.

It is a review about the industrialization of Nano-Optical Microscope (NOM, also referred to as the Near-field Optical Microscope). Two comparisons of AF/PSTM (Transmission Mode) with the first generation commercial A-SNOM and AF/RNOM(Reflective Mode) with A-RNOM have discussed. The commercially used A-SNOM can only obtain a transmissivity image of A-SNOM-T(x,y), but AF/PSTM can obtain the separating the transmissivity image PSTM-T(x,y) and the refractive index imge PSTM-n₁(x,y). AF/RNOM can obtain the lower contrast reflective index image but ARNOM cannot. The reason how could Pohl have obtained the first A-SNOM image with a resolution of 20-25nm in 1984 but the commercial A-SNOM-T(x,y) only with the resolution in the 50~100nm range is also discussed. Conclusion on the proposal of AF/PSTM and combined AF/RNOM may be the best candidate for the second generation commercial use of NOM.

There are much more need to characterize and evaluate performance of IRFPA in field. MRTD, MTF, NETD and operating range R are some of the key parameters of IR devices and used to characterize their performance. Around of these parameters there are two ways: analysis in theory and test. The research of these parameters in theory can be used to predict the performance of IR devices and these parameters can be proved by experiments. Whereas these parameters are hard to be tested in field, their test reports are based on experiment in laboratory. So it is very hard to explain or predict the test results of IR devices in theory because of the influence of atmosphere. This paper presents research of transfer function of atmosphere. A model of transfer function with the modified absorption and scatter coefficient is introduced based on the theory of transfer function. The operating range can be modified by transfer function of atmosphere. The experiment results show this model can be used together with operating range in some circumstances. It could be used in the predicting the operating range of IR devices in theory.

The pyroelectric LiTaO₃ thin film has low heat capacity, low thermal loss, high pyroelectric response and high possibility to make infrared detector, so the LiTaO₃ thin film infrared detector preparation is considered in this paper. During the fabricated experiments, the silicon substrate thickness effect on performance of the LiTaO₃ thin film device is very large, and therefore it has been theoretically investigated by using the MATLAB software and by employing one-dimensional heat conduction equation. The simulation results show the thinner the silicon substrate, the less the thermal loss by conduction, and thus, the higher the pyroelectric response of the LiTaO₃ thin film device. To verify the theoretical analysis, the LiTaO₃ thin film device deposited on the Pt/Ti/SiN_x/SiO₂/Si(100) substrate with different silicon substrate thickness are fabricated and the etching process of the silicon substrate have been discussed in details. The experimental results of the current responsivitiy and the specific detectivity of the LiTaO₃ thin film device agree with the theoretical analysis. The theoretically and experimental results are together determined that, thoroughly etched-off the silicon substrate is the best method to reduce thermal loss and improve the property of the LiTaO₃ thin film device.

Small-molecule organic photovoltaic (OPV) cell with a large open circuit voltage (V_OC) has been achieved by introducing 4-(dicyanomethylene)-2-t-butyl-6-(1,1,7,7-tetramethyljulolidyl-9-enyl)-4H-pyran (DCJTB) as donor layer. In order to obtain large V_OC of standard copper phthalocyanine (CuPc)/C₆₀ OPV cell, a very thin layer of DCJTB was inserted between CuPc and C₆₀. It was found that the device formed multicharge separation interfaces. The VOC of device with 2 nm DCJTB layer was increased from 0.44 to 0.58 V. Also, the atomic force microscope (AFM) 3D-images of the donor surfaces were characterize to discuss OPV cell performance improvement. Furthermore, the absorption spectrum shows that an additional thin DCJTB layer enhances the light harvest capability of the cell.

A new structure of organic light-emitting diode (OLED) was fabricated by inserting a thin molybdenum trioxide (MoO₃) layer into hole transport layer (HTL) N,N'-diphenyl-N,N'-bis(1-napthyl-phenyl)-1,1'-biphenyl-4,4'-diamine (NPB). The device structure is ITO/NPB(10 nm)/MoO₃(3 nm)/NPB (30 nm)/tris-(8-hydroxyquinoline) aluminum (Alq₃) (60 nm)/LiF(0.5 nm)/Al. The control device is set without MoO₃ interlayer. The driving voltage at 100 cd/m² is only 4.87 V corresponding to the device with MoO₃ interlayer, which is much lower than the control device of 6.40 V. The novel device also shows higher power efficiency compared to the control device. The improvement of device performance is attributed to the Charge Transfer complex (CT complex), generated at the NPB/MoO₃/NPB interfaces, contributing here as hole transfer enhancer. Our finding additionally demonstrates the practical applicability of MoO₃ as a buffer layer in OLEDs.

Taking the rectangular hole as an example, this paper addresses the theoretical calculation and experimental observation of Fraunhofer diffraction field when the object plane is inclined to the system optical axis and compares it with that when the object plane is perpendicular to the system optical axis. The author finds in the experiment that the diffraction pattern changes when the object plane is inclined to the system optical axis. The theoretical significance of the paper lies in that it gives a general expression for Fraunhofer diffraction field. The situation that the object plane is perpendicular to the system optical axis is only a particular case for the above expression.

Compared with ordinary linear CCD, one of the most remarkable advantages of TDI/CCD is that it can work under low illumination conditions with imaging clearly. Meanwhile, multiple exposures can reduce pixel inconsistency and the fixed-pattern noise; enhance the Sensitivity and Uniformity of visible light CCD. As a result, TDI/CCD has an extensive application in the aerospace industry. To meet the needs of orientation of TDI/CCD's application towards high-speedy, miniaturization and intellectualization, in this paper,Fairchild Imaging CCD525 is chosen as image sensor,by means of programming on XC2V1000 which is one type of Virtex-II serials FPGA, using the key technology such as IP reuse,DCM and timing constrain, realized the functions of real-time adjustment of TDI integration time,number of integration stages,VGA gain and digital quantitative deviation. The whole system not merely passed the software simulation on ModelSim,and achieved satisfactory effect in practical application.

A new type of accelerometer is advanced which is based on optical fiber multi-mode interference (MMI). We use a structure that a multi-mode fiber connected to two single mode fibers as the sensing part of the accelerometer. By measuring the changes of the output spectrum can get the acceleration. This paper describes the principle of the accelerometer based on multi-mode interference, and a theoretical simulation is performed. In the experiment a Piezoelectric Ceramic is applied to simulate the Static Acceleration. The result manifests that this type of accelerometer has a great dynamic range and a good resolution, also it's easy to fabricate and low cost.

A new hydrogen-bond acidic carbosiloxane polymer for quartz crystal microbalance sensors (QCMs) application was synthesized via O-alkylation, Claisen rearrange, hydrosilylation reaction and functionalized the polysiloxane with trifluoroacetone groups (TFA). The trifluoroisopropanol functionalized polysiloxane was characterized by FT-IR and ¹HNMR. And this novel siloxane polymer was coated onto AT-cut 8 MHz QCM sensors to investigate its gas sensitive responses to the organophosphorus nerve agent stimulant dimethyl methylphosphonate (DMMP) vapor as well as other interfering organic vapors. The research work indicated that frequency shifts of the trifluoroisopropanol functionalized polysiloxane based QCM sensor to the DMMP vapor were completely linear, and with a regression coefficient of 0.9973 in the concentration range of 10-60 ppm. In addition, the sensitivity of the fabricated QCM sensors to DMMP was up to 10.64 Hz/ ppm, and much higher than the other interfering vapors, limits of detection (LODs) of the QCM sensors was 0.28 ppm, thus high selectivity to DMMP was demonstrated in this work.

This work studied the formation of spatial solitons in a SBN: 75 photorefractive crystal by 532 nm continuous-wave laser beam from a single frequency solid laser. It was found that the behaviors of the spatial solitons varied with background light. While white light and 632 nm red light are used as background, the solitons perform like first-order light soliton. The compressed-amplitude, in measured with laser beam's size before and after passing the crystal, is proportional to the applied voltage of a dc electric field, i.e., they are quasi-steady-state solitons formed in a time window. However, as the background is changed to an incoherent 532 nm light output from the same laser, the solitons vary periodically and the compressed-amplitude is not proportional to the voltage of applied dc electric field any more. In this case, solitons form instantaneously at applied field of 900 V/cm and hold the shape for 7 seconds which is less than the one with white or red light as background, and then break slowly. We tried to present reasonable explanation for above observation.

How to see the stars in daytime? A new idea is described here in this paper which uses a combination of two methods: one is traditional spectral filtering method and the other is a new attempt on daytime star detection--polarization method. Each of these two method's principle of work, scope of application and limitation on daytime star detection are introduced in detail; and the advantage of the combination is discussed accordingly. Based on the demand of the daytime star detection, a device is designed and its optical system and mechanical structure are also analyzed in this paper. At last, a further discussion of the existing problems and the possible improvements of the current device are presented.

In order to resolve the problem of quantitative identifying, in pulsed thermography, taking the highest temperature difference and the best testing time as input, and taking defect depth and diameter as output, made use of BP Neural Networks to achieve it, and it was done. According to result, when testing value was in area of swatch, identifying precision was high, and error is less than 3.5%. The feasibility of BP Neural Networks was validated, and it has very important meaning to quantitative identifying of factual application.

Quantum teleportation is an important component element of quantum information theory and is an effective method to realize quantum communication. This paper presents the realization method and survey technology of quantum teleportation, introduces the theory and experiment research process of quantum communication field and its broad prospect.

The effect of carrier gas on thick GaN film grown by hydride vapour phase epitaxy on (0001) sapphire substrate has been studied by double crystal X-ray diffraction (DCXRD), field emission scanning electron microscope (FE-SEM), photoluminescence (PL) and Hall tester. H₂, as carrier, is propitious to two-dimension growth pattern of GaN film, but it causes production of more defects and impurities. Red shift of band edge emission of PL and a wider FWHM (full wave at half maximum) of DCXRD appear under H₂ atmosphere. N₂, as carrier, reduces the content of defects and impurities. However, the growth interface of GaN forms easily crystallographic facets but not epitaxial (0002) plane, which leads to appearing of embossed surface. It may gain high-quality HVPE-GaN that H₂ and N₂ are adopted as carrier gas sequentially.

A double CCD Camera 3D measurement system, which is based on the Marr vision calculation theory, classical disparity imaging theory and stereo model, was designed. Method and related techniques have been described in this paper after analyzing and comparing deferent kinds of 3D testing methods, which provide references for the setting up of hardware system. Based on both eyes vision model, a set of 3D testing program based on disparity is designed. By analyzing the sample data: while the confidence is 0.99, the system precision is 0.01mm.

Thermal inertia and finite heat conduction make the acquired temperature from temperature sensor be not reliable enough. So, it is necessary to make a dynamic calibration to the sensor. The frequency-response characteristics of high speed radiation thermometer surpass that of the temperature sensor; therefore it can be used as the reference value to calibrate the latter and let system error is corrected. The traceable dynamic calibration method is used to calibrate CHAL-010 thermocouple (manufactured by OMEGA Company). The thermocouple's time constant as well as error correction value of dynamic temperature measurement is obtained from it. The traceability is accomplished successfully through unbroken chain of comparisons with appropriate standard at the system.

A new time constant measurement means of the surface temperature sensor is proposed, in which a high frequency modulated high power CO₂ laser acts as the driving source. The measurement system is designed and practiced in thermocouples with different temperature ranges. It is proved that the system can be used to measure transient surface temperature sensor which be with a time response from the sub-millisecond level to the second level, and the temperature provided by the driving source can range from the room temperature to the high temperature.

Preliminary site testing shows that Antarctic inland Dome A is likely to be the best astronomical observatory site on the ground, Chinese first Antarctic astronomical equipment CSTAR has been successfully run Dome A. Three Antarctic Schmidt Telescopes (AST3) is the next important Antarctic astronomical equipment, one of which will be mounted Dome A. In the year of 2010, and the three will be installed Dome A finally. Because of the very low temperature and saturation vapor pressure, and the temperature gradient changes fast near the ground layer at Dome A, the mirror is easy to be frosted, which is one of difficulties to AST3.Indium Tin Oxide (ITO)is an N-type semiconductor material, because it has few resistors, good light transmission, good weather resistance, small environmental impact, low cost, and it is easy for large area coating, so it is widely used in many fields. The mirror is heated by ITO that is coated on the surface of the mirror, the voltage on the ITO will be tuned by changing the output pulse width, and then the system achieves a closed-loop control. The difference between the mirror temperature and ambient temperature will be maintained in an ideal range, and this will not only ensure that the mirror surface will not get frosting, but to minimize the impact of mirror seeing to guarantee the image quality of the telescope. The experimental results show that the temperature control system can control the different temperature between the mirror surface and the ambient less than 2 degree in real time, which can improve the mirror's working environment, and the overall effectiveness of the telescope's observations.

Viewing angle changeable display can change the display viewing angle as needed: In the public place the display could have a narrow viewing angle for privacy, while in the private place the displays could have a wide viewing angle for the convenience of the operation and better viewing experience. This article propose a novel adjustable optical transmission device to realize the viewing angle changes for LCD by using the principle of guest- host effect of liquid crystal. The major technology is to insert a special equipment between the backlight and the LCD, through which the backlight will display either parallel or scattered features to get an either narrow or wide viewing angle. The equipment is an adjustable transmission cell (ATC) which is actually a black G-H LC cell. This ATC is the main focus of our invention. The ATC consists of a polarizer sheet and a special guest-host liquid crystal device filled with the two-phase dye (called as GH-LC in this report), to achieve the viewing angle change in the LCD. When an electrical field charges to the ATC, only the so-called near-axis lights can pass through the ATC within a relatively small angle, while the other scattered lights are absorbed sequentially by GH-LC and the polarizer sheet. On the other hand, when there is no electrical charge to the ATC, the cell behaves like a normal polarizer; and the scattered light can pass through the cell and polarizer in a normal way. This paper describes the principle and structure of the device, applies the electric field on the sample to observe the electro-optical properties, combine the theoretical and experimental research, getting the viewing angle effects of the display.

The paper discusses the circuit design and working principles of VMOS PWM type 75KV10mA high frequency X-ray machine. The system mainly consists of silicon controlled rectifier, VMOS tube PWM type high-frequency and highvoltage inverter circuit, filament inverter circuit, high-voltage rectifier filter circuit and as X-ray tube. The working process can be carried out under the control of a single-chip microcomputer. Due to the small size and high resolution in imaging, the X-ray machine is mostly adopted for emergent medical diagnosis and specific circumstances where nondestructive tests are conducted.

In order to improve the radiation hardness of free-space optical communication system, this paper theoretically deduces the radiation damage model of laser diodes' output power. For this model, the theory of Gaussian distribution is used to study the radiation influence on detection threshold of free-space optical communication on the condition that the bit error rate keeps invariable. The result shows that both the output power and detection threshold are the linear functions of total dose.

Mechanical vibration is the main source limiting and damaging the resolution of aerial cameras. It is necessary to stabilize the line of sight (LOS) to guarantee the image quality. Using dynamic MTF to evaluate image quality and establish reasonable stabilization system performance standard, is a common artifice during the design process. Linear motion and high frequency vibration MTF have been expressed in closed form; however, low frequency vibration still cannot be solved analytically. A numerical dynamic MTF calculation method was developed. With this method and corresponding results, the image quality as well as affordable residual vibration under particular oscillations can be predicted. As a result, passive isolators and other image system devices can be selected effectively and properly.

The high brightness InGaAlP light emitting diodes(LED) is a novel solid-state lighting in recent years. As the absorption of the red light by the GaAs substrates decreased external quantum efficiency, the development and application of LED are limited. If all the light incident to the substrate can be reflected, the influences of substrate absorption are radically improved. Therefore, a novel distributed Bragg reflector(DBR) is proposed. The defect layer whose crystal lattice constant matched with the substrate grows among the DBR to change the reflectivity spetrum by regulating the defect layer meterial and thickness. According to matrices-optic theoretics, analogically compute the reflectivity and transmission spectrum of Al_0.5Ga_0.5As/AlAs DBR in which has defect layer, corresponding to the wavelength is 610nm and period is 15. The experimental results show that the reflectivity is not less than 0.6 as the incident angle is greater than 45°. Hence, a novel method is obtained for enhancing the LED external quantum efficiency.

Laser altimetry is a new measurement technique. Altimeter receives the return signals after launching laser pulses to the ground. Three-dimensional information on the ground is obtained by analyzing the corresponding relationship between return signal features and topographical features. But there is an apparent deficiency when using the data points to establish the three-dimensional DSM. That is the accurate time information of the return signal cannot be obtained when positioning the edge lines of the ladder terrain. In this article, the distribution of the echo waveform over the ladder terrain of city buildings is simulated by a self-designed altimeter waveform simulator under different direction angles and parameters of the terrain. The best extraction method of the return time information at the edge line is identified by analyzing the waveform characteristics at the edge line of this terrain, which enhances the accuracy of applications of the ladder terrain modeling. The time information of the return signal is extracted under various parameters by applying five methods which are accepted internationally, namely Peak point, Mean point, 50% Rise time point, Center of Area point, and Midpoint. Then the experiment values are compared to the actual values. According to the results of the simulations, the difference between the experiment value of the 50% Rise time point and the actual value is minimal. Its resolution ratio is about ten time units maintaining in a narrow range. It proves that this method can effectively improve the accuracy of the extracted time information of the return signal at the edge line over ladder terrain. And it provides a valid data source for establishing a more accurate DSM model.

The active photo-excited carrier has been identified in reverse biased quantum dot resonant tunneling diode (QDRTD) for light detection. The QD is embedded on the AlAs/GaAs/AlAs double barrier part of the material structure and is found with strong charge memory effect. The QD is charged with electrons in forward bias and the charge storage of QD is maintained well in reverse bias until the voltage of QD resonant tunneling peak. With this charge memory effect, the photo-excited holes are charged into QDs in forward bias and still influence the reverse bias behavior of QDRTD at dark. Compared to the illuminated QDRTD in reverse bias, the active photo-excited carrier of reverse biased QDRTD is unambiguously identified as photo-excited holes. The potential profile of QDRTD structure is also calculated and the potential near charged QDs is found greatly pushed up above GaAs E_C. This may explain the trapping of photo-excited hole by QD for QDRTD in reverse bias.

Position sensitive detector (PSD) is based on the lateral photoelectric effect (LPE) to produce an electrical. The photocurrents output from the electrodes, so the amplitude and phase of the output signal are related to the distance between the light spot and the electrodes. The information of the phase was detached from photocurrent signal. The diversification of phase along with the distance was analyzed, and phase difference between the corresponding electrode signal current as well as the associated difference with the change of PSD related parameters. The result of experiment on one-dimensional and two-dimensional PSD is shown that the position detection error and the linearity all can meet the test requirements.

In this paper, a novel Human-Computer Interaction (HCI) system based on IR tracking technology is proposed for big projection screen real-time HCI applications. The proposed system has been successfully applied in a multiple-user shooting game. In this system, each user holds an interactive device, which is based on an ADSP-BF533 hardware platform, to interact with the shooting game on the big projection screen. IR tracking technology is introduced and theories for projective transformation are studied in detail. A fast IR marker identification algorithm is developed for real-time interaction. Two groups of IR markers are adopted in the proposed system for IR tracking, which are fixed on the border of the big projection screen. To utilize the theories for projective transformation, each group of IR marker is composed of 4 IR LEDs with a rectangular arrangement. There is a CMOS sensor inside each interactive device to capture the image of IR markers. The captured image is then used for image processing and IR marker identification on the ADSP-BF533 hardware platform. According to the theories for projective transformation, the target position on the big projection screen of each interactive device can be obtained after the projective transformation from the CMOS image to the big projection screen. An experimental environment is set up and experiments are implemented to test the validation of the performance of the IR marker identification algorithm, i.e. tracking accuracy, time consuming and effective region of the proposed system. Experimental results show that the proposed system is very efficient and robust for big projection screen interaction application. The IR markers can be correctly identified with the identification algorithm developed in this paper. Experimental results also show that the developed system can achieve real-time processing and work with high tracking accuracy. The proposed system works well in a large effective region that allows multiple-user interaction. Moreover, the proposed system can be extended to bigger projection screen interaction applications with the adoption of more groups of IR marker.

The applications of Fiber Bragg grating (FBG) sensors have been concerned considerably for many years. However, it is usually difficult to obtain an accurate result by single FBG in practical applications, since the phenomenon of cross sensitivity caused by the multi-external fields always exists. In the past, most of researchers presented their studies only on the cross sensitivity of two parameters including temperature and axial strain, temperature and transverse pressure, and so on. Actually, FBG sensors might be affected by temperature field, axial strain field and transverse pressure field simultaneously in some applications, but no previous analysis has been presented on the cross sensitivity caused by these three parameters. This work extends the previous works on the cross sensitivity of two parameters to that of three parameters in a FBG sensor. The sensing model of FBG in three external fields is deduced and analyzed theoretically from the perspective of its physical mechanism, through which the expression of the cross sensitivity function is obtained. Meanwhile, examples of different external physical factors and fiber parameters are considered for illustration purposes, and the cross sensitivity term is discussed by the numerical simulation. The simulated results show that the properties of cross sensitivity would change in a certain regulation with the changes of external effects and fiber parameters. Compared to the two-parameter analyzing method, this work makes a more comprehensive analysis to the research object. Some valuable suggestions about how to reduce the systematic error and improve the measurement accuracy are put forward as well.

In the Λ three-level system, we will make use of semi-classical density matrix method to analyze cesium (Cs) hyperfine structure of coherent population trapping (CPT) phenomenon. Coherent population trapping has been widely used in electromagnetically induced transparency, non-inversion laser, optical storage and ultra-slow speed of light fields, then strong-coupling light and weak detecting light form coherent laser light to change the hyperfine structure energy levels of particles number distribution, which impacts on laser pumping magnetic resonance. In this paper, we will discuss the theoretical analysis and system design of laser pumping cesium magnetometer, cesium atomic energy level formed hyperfine structure with the I-J coupling, the hyperfine structure has been further split into Zeeman sublevels for the effects of magnetic field. To use laser pump and RF magnetic field make electrons transition in the Zeeman sublevels to produce the results of magneto-optical double resonance and on this basis we analyze the influence of laser pumping magnetic resonance based on coherent population trapping.

Negative electron affinity (NEA) Gallium Nitride (GaN) photocathode is an ideal new kind of UV photocathode. NEA GaN photocathode is widely used in such fields as high-performance ultraviolet photoelectric detector, electron beam lithography etc. The preparation of negative electron affinity gallium nitride photocathode relates to the growth technology, the cleaning method, the activation method and the evaluation of photocathode. The mainstream growth technology of GaN photocathode such as metal organic chemistry vapor phase deposits technology, molecule beam epitaxial technology and halide vapor phase epitaxial technology were discussed. The chemical cleaning method and the heat cleaning method for GaN photocathode were given in detail. After the chemical cleaning, the atom clean surface was gotten by a 700 °C heat about 20 minutes in the vacuum system. The activation of GaN photocathode can be realized with only Cs or with Cs/O alternately. Using the activation and evaluation system for NEA photocathode, the photocurrent curve during Cs activation process for GaN photocathode was gotten. The evaluation of photocathode can be done by measuring the quantum efficiency. Employing the UV spectral response measurement instrument, the spectral response and quantum efficiency of NEA GaN photocathode were measured. The measured quantum efficiency of reflection-mode NEA GaN photocathode reached up to 37% at 230 nm.

The method of Spatial convolution is applied to analyze the imaging process of the CCD imaging system, which involves optical imaging process and CCD integral sampling process, and the ratio between GRD and GSD that is called Kell coefficient is introduced, based on which, analysis of effect of Kell coefficient on the quality of aerial photography is educed. Imaging process of the target is simulated with different Kell coefficient values by matlab. The method of the gray difference between the target and the image on CCD which is regarded as the evaluation criteria is proposed to evaluate the image quality. The simulation results show that when Kell coefficient equals 2.8, the target characteristics can be distinguished.

BaAl₂Si₂O₈:xEu²⁺, yMn²⁺ was prepared by high-temperature solid state reaction and X-ray powder diffraction analysis confirmed the formation of it. It was found experimentally that, its emission peaks situated at 420 nm and 570 nm respectively under excitation of 380 nm irradiation. The emission peaks at 420 nm originate from the transition 5d to 4f of Eu²⁺ ions that occupy the Ba²⁺ sites in the crystal of BaAl₂Si₂O₈, while the 580nm emission is attributed to the energy transfer from Eu²⁺ ions to Mn²⁺ ions. The white light can be obtained by combining the 380 nm chip with the phosphor. When the concentrations of the Eu²⁺ ions and Mn²⁺ ions were 0.05 mol and 0.35 mol respectively, the sample presented intense white emitting. The near-ultraviolet InGaN-based BaAl₂Si₂O₈:0.05Eu²⁺, 0.35Mn²⁺ LED achieves good color rendering of 85 with the CIE coordinate of (0.3183, 0.3036).

The location and identification of targets in grey images could be determined by wavelet space frequency domain identification filter according to coherent space frequency domain technology. Also the infrared spectrum radiation distribution about the targets could be got by the same algorithm. By making a comparison between the coherent and non-coherent wavelet space frequency domain filtering algorithms, we knew the former way could filter most clutter noises, leaving the primary elements about the targets. Both from target grey images and spectrum radiation, the primary content involved in the target images could be stressed by the former way. Especially more important is the extraction of target signatures by use of the coherent wavelet space frequency domain filtering algorithm in the spectrum radiation domain.

A class of wide band-gap semiconductor offers an attractive alternative to Si and X-ray diode (XRD) detector technologies for x-ray detection in Inertial Confinement Fusion (ICF) experiments. Because diamond presents high thermal conductivity, resistance and breakdown field, fast charge collection, low leakage current, wide band-gap, low dielectric constant, large carrier drift velocity and outstanding radiation hardness. Using chemical vapor deposited (CVD) technology, 1 mm×1 mm×2 mm, 1 mm×1 mm×3 mm diamond was synthesized. And the detectors were fielded with metal-semiconductor-metal structure. Characteristics of the detectors have been studied on a pulse laser equipment. The results indicate that the rise time and FWHM of the detector reach 60 ps and 120 ps respectively.

We have investigated the geometrical structures, the electronic properties, and the formation energies of nN-Mg codoped ZnO in neutral state by adopting the first-principles calculations based on the density function theory (DFT). The calculated results indicate that N atoms prefer to occupy the substitution O site and Mg substitutes the Zn site of the nearest site of N, which act as an acceptor. Compared with the formation energies of various configurations in neutral state, it is found that 4N-Mg complex has the lowest formation energy using NO as dopant resource under Zn-rich condition, indicating that 4N-Mg codoping can enhance the N dopant solubility under this condition. Meanwhile, the Znrich condition is better for p-type doping than the O-rich condition. It demonstrates that 4N-Mg complex is in favor of achieving p-type conduction in ZnO. Simultaneously, analysis of density of states (DOS) of nN-Mg complex find that the valence band maximum (VBM) has a little raise near the Fermi energy level, indicating that the complexes are the typical p-type characteristic. However, for 4N-Mg complex, the Fermi level is located near the top of valence band. Furthermore, from the band structure and PDOS of 4N-Mg complex, it is observed that the complex produces an additional impurity band at the top of the valence band. Meanwhile, the PDOS value of 4N-Mg complex at the Fermi level is relatively large. In addition, 4N-Mg complex has much lower ionization energy of 0.167eV than that of other complexes. Therefore, better quality p-type conductivity is achieved by codoping 4N-Mg in ZnO.

The way of improving the thickness uniformity of the thin film deposited by magnetron sputtering system is presented in this paper. A simple model for the magnetron sputtering system with a baffle between cathode target and substrate is described. Based on this model, it is possible to predict the relative deviation of film thickness with this baffle-model by taking the shape and size of baffle into the consideration. The purpose of this article is to explain how different baffle parameters affect the uniformity of thin film using the method of finite element with rectangle target in this magnetron system. It is found that there may exist optimum baffle conditions where the relative deviation of thin film thickness is less than 3 % with a diameter of Φ 150 mm substrate.

A systematic simulation based on Berg's model and theoretic study of co-reactive sputtering of titanium and vanadium targets is presented. It enables one to predict the hysteresis effect and intermediate composition of the deposited film as a function of different targets current in the co-reactive sputtering process. With this approach, it is possible to obtain different stoichiometry of thin film by choosing different ratio of vanadium target current to titanium target current. In this case, the material composition in the thin film with respect to the fraction of these two targets current can be optimized. Finally, the deposition rate of co-reactive sputtering as a function of total sputtering rate of two metal material atoms is also described.

The emission dynamics properties of InAs self-assembled quantum dots (QDs) embedded in InGaAs/GaAs quantum well with different strain reducing layer (thin InAlAs and GaAs) were systematically investigated by time-resolved and temperature dependent photoluminescence (TR and TD PL) measurements. We observe that a thin 10 monolayer (ML) GaAs layer may increase the emission wavelength, and 1 nm additional InAlAs layer results a significant nonlinear redshift of above 1.3 μm photoluminescence (PL) peak, which can be explained from the strain analysis. TDPL spectra display an anomalous enhancement behavior of the integrated PL intensity around 150 K for the InAs QD structures without the InAlAs layer, which may be described by the reduced carrier transition at higher temperature for the higher energy barrier of the InAlAs layer. We study systematically PL decay time of the InAs with different structures. The PL lifetime of quantum dots grown on a 10 ML GaAs layer is a littler longer than those without the layer, and a more InAlAs layer may result in a greatly increase of PL lifetime, which implies that the InAlAs layer with higher energy barrier may enhance the quantum restriction of carriers in InAs QDs. The above phenomena also approve the facts that the main mode of carrier migration is quantum tunneling effects at lower temperature, while it is the quantum transition at the higher temperature. We explained these measuring results from the competition between the carrier recombination, escape and redistribution.

At present, the domestic and international third-generation anti-tank missiles, laser-guided missiles are mostly divided into active laser-guided and laser semi-active guidance, this guidance system, there are vulnerable to electronic interference, can not be fully realized after launching deficiencies. Article based on this, an in-depth understanding of imaging-guided laser-active working principle, based on the pairs of third-generation anti-tank missile guidance system, boldly proposed to improve the anti-tank missiles, laser-active small-scale integration of imaging guidance system design, the main purpose is to improve a certain type of The optical target missile, TV angle measurement, laser-guided instruction transmission means, so that anti-tank missiles to achieve forward-looking, the next obstacle avoidance TV and multi-functional integration of the entire after launching smart missiles, and in theory be able to study the new antitank missiles play a certain reference.

In recent years, TiO_2-δ thin films as a kind of thermal sensitive material have been attracting more and more attention on the application of infrared devices. In this article, TiO_2-δ thin films from the technology of DC reactive magnetron sputtering were deposited on glass substrates under the same sputtering conditions while different annealing conditions. Annealing effects on electrical properties and thermal sensitivity characteristics were systematically investigated under different annealing conditions including annealing circumstance, annealing time and annealing temperature. Results indicated that the sheet resistance (R) and temperature coefficient of resistance (TCR) of TiO_2-δ thin films would decrease after vacuum-annealing and would increase after oxygen-annealing. Furthermore, they would increase more and more when the annealing time and the oxygen flux increased during oxygen-annealing. On the contrary, R and TCR would decrease when the annealing temperature went up. Based on that, TiO_2-δ thin films could be better applied on related devices under proper technique of annealing.

It presents a new approach for detecting building footprints in a combination of registered aerial image with multispectral bands and airborne laser scanning data synchronously obtained by Leica-Geosystems ALS40 and Applanix DACS-301 on the same platform. A two-step method for building detection was presented consisting of selecting 'building' candidate points and then classifying candidate points. A digital surface model(DSM) derived from last pulse laser scanning data was first filtered and the laser points were classified into classes 'ground' and 'building or tree' based on mathematic morphological filter. Then, 'ground' points were resample into digital elevation model(DEM), and a Normalized DSM(nDSM) was generated from DEM and DSM. The candidate points were selected from 'building or tree' points by height value and area threshold in nDSM. The candidate points were further classified into building points and tree points by using the support vector machines(SVM) classification method. Two classification tests were carried out using features only from laser scanning data and associated features from two input data sources. The features included height, height finite difference, RGB bands value, and so on. The RGB value of points was acquired by matching laser scanning data and image using collinear equation. The features of training points were presented as input data for SVM classification method, and cross validation was used to select best classification parameters. The determinant function could be constructed by the classification parameters and the class of candidate points was determined by determinant function. The result showed that associated features from two input data sources were superior to features only from laser scanning data. The accuracy of more than 90% was achieved for buildings in first kind of features.

We investigated the up-conversion fluorescence characteristics of the bismuth doped silica fibers with and without Al codopant (BA fiber and BI fiber). Unusual up-conversion fluorescence was discovered in both of these two fibers when excited by pump lasers. After more experiments, it was found that the BI fiber showed more complicated and distinct upconversion spectrum than the BA fiber, but with different and weaker NIR emission as we reported before. And it was implied that the up-conversion fluorescence should be mainly responsible for the Bi²⁺ ions which was rich in BI fiber. Thus, by properly improve the Al co-doping concentration could alleviate the fluorescence up-conversion thus improve the efficiency of the NIR band fluorescence. Besides, the complicated up-conversion fluorescence bands may helpful to clarify the energy levels of the Bi ions in silica materials.

Photoconductive GaAs/AlGaAs quantum well infrared photodetector (QWIP) achieves best performance when the well has its first excited state resonant with barrier height. Optimum QWIP structure parameters can be designed according to this rule. The parameters calculated by simple square well model taking account of variable effective mass are not accurate enough and can merely provide a rough estimation for actual QWIP devices. Higher order effects including band nonparabolicity, quantum confined Stark-effect and Coulomb interaction of large number of charge carriers (also known as Many-body effect) can have considerable influence on the energy level of quantum wells. Band nonparabolicity effect was included in the calculation in this paper. And a group of optimized GaAs/AlGaAs n-type QWIP structure parameters covering wavelength from 7 μm to 16 μm were systematically calculated, using one band effective mass approximation (EMA) and shooting method. These calculated results were carefully compared with those where band nonparabolicity was not considered, and 4 ± 2% discrepancy was found. Since a photoconductive QWIP normally works under a certain bias, change of the confined state energy level and shift of peak wavelength caused by the quantum confined Stark-effect were calculated and discussed. All the calculated quantum well structure parameters in this paper will offer a more accurate guide for QWIP fabrication.

Liquid crystal writable grating technology is being developed for beam steering in laser radar systems. It is ability to steer broad-spectral -band radiation for us in passive sensors. There is potential for these devices in microscan systems because there is little or no dispersion for the small scan angles required in microscanning. The dispersion that is less than the resolution of the sensor considered here. For large angle steering, the dispersion correction or a narrowing of the spectral bandwidth is required. The degradation in sensitivity resulting from narrowing the spectral bandwidth is considered. A high quantum efficiently step-stare sensor with a two-dimensional focal plane array responsive over a narrow spectral width can achieve the same sensitivity as current linear scanning sensors while being able to steer the field of view(FOV) over a larger field of regard with no moving parts. A promising approach for steering a narrow FOV with broad spectral content and good resolution is described.

The methods of detecting small moving targets in infrared image sequences that contain moving nuisance objects and background noise is analyzed in this paper. A novel infrared small target detection algorithm based on improved SUSAN operator is put forward. The algorithm selects double templates for the infrared small target detection: one size is greater than the small target point size and another size is equal to the small target point size. First, the algorithm uses the big template to calculate the USAN of each pixel in the image and detect the small target, the edge of the image and isolated noise pixels; Then the algorithm uses the another template to calculate the USAN of pixels detected in the first step and improves the principles of SUSAN algorithm based on the characteristics of the small target so that the algorithm can only detect small targets and don't sensitive to the edge pixels of the image and isolated noise pixels. So the interference of the edge of the image and isolate noise points are removed and the candidate target points can be identified; At last, the target is detected by utilizing the continuity and consistency of target movement. The experimental results indicate that the improved SUSAN detection algorithm can quickly and effectively detect the infrared small targets.

In gas discharge, various self-organized structures are formed as the applied voltage is increased. A noticeable phenomenon is that the system undergoes twice hexagon structure. One is observed in the lower voltage range and the other is in the higher voltage range. To study the intrinsic mechanism, the light signal, electric signal, and the emission spectrum of the two hexagons is measured by photoelectric detect method. The electric signal is detected by high-voltage probe. The light signal is measured distinguished in time and space by using diaphragm. The electron excitation temperature is measured using spectrum method. It is conclude that the forming mechanism of the two kinds of hexagon is different. The lower-voltage hexagon is a dynamic multiplex structure, while the higher-voltage hexagon is a single static structure. The excitation temperature of higher-voltage hexagon is higher than that of lower-voltage hexagon.

With the rapid development of optoelectronic tracking and measurement technology, tracking equipments become more complex and more precise, and the system faults happen at higher probability. The fault orientation, the fault analysis and the fault exclusion change more difficult. The single information and the simple process of multi-information have many deficiencies, which need fusion to improve the reliability. The D-S theory of evidence is a way to resolve the uncertain problems, which fuses evidences to reason the decision results in the same recognition frame used at the decisional level. Using the D-S theory of evidence, a diagnosis frame of multi-feature information fusion is proposed. The deviation ranks of the fault characters is defined according to their offsets from the normal and their happening probabilities were also computed by using the statistical results and the existing knowledge. The data reasoning of rough set theory is employed to construct the key fault evidence space from the multi features. Further, Gaussian subjection function from the fuzzy theory is used to describe the distribution of the key evidences and the distribution of the test data, and the basic probabilities of the evidence are weighed by the matching degree of the two distributions. The multiperiod and space feature information are employed and fused, and the final diagnosis decision is made by some effective methods. A multi-feature information fusion diagnosis for the servo system of the tracking equipment is discussed. The test shows that the diagnosis reliability is improved and the diagnosis uncertainty is reduced, and the fault diagnosis for the precise device and other parts are also effectively resolved by using this fusion method.

Vanadium oxide films were prepared onto glass and KBr substrates at various deposition temperatures by DC reactive magnetron sputtering. X-Ray photoelectron spectroscopy (XPS), Atomic force microscope (AFM), Fourier transform infrared spectroscopy (FT-IR) were employed to analyze the VOx films, respectively. Experimental results indicated that deposition temperature has a great impact on the surface morphology of vanadium oxide films. The XPS analysis confirmed that the vanadium oxide films prepared are V₂O₅. From Fourier transform infrared spectroscopy, it can be see that the infrared active mode corresponding to V-O-V stretching vibration and the stretching vibration of unshared V=O bonds appeared at about 840 cm^-1 and 915 cm^-1 in the films formed at 240 , respectively. A shift in the peak position towards higher frequency was found with increasing the deposition temperature which indicated that the films formed at higher deposition temperature were structural disorder.

The modulation transfer function (MTF) is measured at different illuminance in order to guarantee the veracity of measuring MTF of the third generation low-light-level image intensifier, the measuring result is analyzed. It is concluded that the law of MTF and illumiance, which is valuable for measuring MTF of the third generation low-light-level image intensifier and similar device.

The microcrystalline silicon films in the phase transition regime from amorphous to microcrystalline were fabricated by microwave electron-cyclotron-resonance chemical vapor deposition (MWECR CVD) system. The influence of deposition temperature and deposition pressure on the structure and electrical properties of microcrystalline silicon films was investigated. It is shown that the films in the phase transition regime from amorphous to microcrystalline are easier to fabricate under the condition of lower deposition pressure and higher substrate temperature. For example, the films in the phase transition regime whose crystalline volume fraction is about 30 %, were deposited at substrate temperature of 170 °C and deposition pressure of 0.7 Pa. The films' μτ product is about the order of magnitude of 10^-5, whose magnitude is two order higher than that of amorphous silicon films, and their photosensitivity is about 10³~10⁴. Therefore, having both high stability and excellent optoelectric properties of the high-quality and device grade film, it is suitable to fabricate the intrinsic materials for amorphous silicon based solar cells.

The CCD plane of the space tridimensional mapping camera will be deviated from the focal plane(including the CCD plane deviated due to camera focal length changed), under the condition of space environment and vibration, impact when satellite is launching, image resolution ratio will be descended because defocusing. For tridimensional mapping camera, principal point position and focal length variation of the camera affect positioning accuracy of ground target, conventional solution is under the condition of vacuum and focusing range, calibrate the position of CCD plane with code of photoelectric encoder, when the camera defocusing in orbit, the magnitude and direction of defocusing amount are obtained by photoelectric encoder, then the focusing mechanism driven by step motor to compensate defocusing amount of the CCD plane. For tridimensional mapping camera, under the condition of space environment and vibration, impact when satellite is launching, if the camera focal length changes, above focusing method has been meaningless. Thus, the measuring and focusing method was put forward based on astigmation, a quadrant detector was adopted to measure the astigmation caused by the deviation of the CCD plane, refer to calibrated relation between the CCD plane poison and the asrigmation, the deviation vector of the CCD plane can be obtained. This method includes all factors caused deviation of the CCD plane, experimental results show that the focusing resolution of mapping camera focusing mechanism based on astigmatic method can reach 0.25 μm.

The technique of weak small target detection and recognition has been the key technique of the electro-optical detecting system, many scholars are engaging the research of detection for weak and small targets. The effective detection for small targets in low SNR images is still a hot research field. Because infrared sensor is easily affected by atmosphere hot radiation, long distance and sensor noise, the detected targets in infrared images often present like small targets and drowned in noise. The basic problem inherent to extent the detection range is the detection of small, low observable, no obvious structural information in images and complicated background. In order to improve the detection ratio of weak small targets and decrease the false alarming ratio in the condition of complicated background, the paper presents the technology of pretreatment of infrared images and the technology of detection for weak small targets, mainly including the technology of Sobel edge algorithm and multi-degree and multi-orientation gradient. Based upon horizon-correlative characteristic of infrared images which were gotten by scanning, considering of the target properties in complicated background, an algorithm of weak and small target detection is presented. Because the images appear horizon-correlative characteristic, Sobel horizontal operator is adopted. By this algorithm, the background clutter was suppressed. Then an adaptive threshold was proposed to extract the precise location of small target. Incorporated with the two methods, a single frame weak and small target detection algorithm was built. Its high performance was then proved in a serial of experiments. In order to solve the detection problems of weak and small infrared targets under complicated background, a detection algorithm integrating with multi-degree and multi-orientation gradient fusion is proposed. Based on the principle of infrared radiation property of target, i.e., the gradient variations of pixel gray scale in horizontal and vertical directions, the algorithm handles the property of weak and small target into analysis of image singularity and detects targets by means of multi-degree gradient step length. Then the detected results show this method can remove most false targets. As a result, the algorithms have fulfilled the engineering demands for reliability and real-time property.

Silicon nitride (SiNx) thin films were deposited by low frequency (LF) plasma enhanced chemical vapor deposition (PECVD) technology. By systematic variation of the process parameters, e.g. reactive gas flow rate, LF power, chamber gas pressure and substrate temperature. Influences of above parameters on the intrinsic stress of SiN_x films were studied and analyzed by combining with the measured refractive index (RI), density, infrared spectra results of deposited SiN_x films. The results showed that intrinsic stress of SiN_x film was roughly proportional to film density, which was inversely proportional to hydrogen content in the SiN_x film. Substrate temperature during deposition was the most important factor affecting hydrogen content in deposited film and, accordingly, the density and intrinsic stress of SiN_x film.

The detection of explosives and related compounds is important in both forensic and environmental applications. In this paper, we report on the preparation of novel plastic optical fiber explosive sensor based on fluorescence quenching. A low priced LED light source and PIN detector were used in this sensor system, a U-shaped plastic optical fiber with high sensitivity act as sensor head. We use amplifying fluorescent polymers (AFP) MEH-PPV as fluorescence indictor. MEHPPV was dip coated on to the surface of the U-shaped plastic optical fiber. For the first time as far as we know we detected the fluorescence lifetime by the phase-fluorometry method to measure the concentration of TNT, which has a merit of immunity to fluctuation of the light source and is more reliable than measuring intensity alone. In the experimental set-up the phase shift between excitation light and fluorescence is calculated by correlation method. Two degree phase difference was measured when the sensor head was exposed to TNT vapor and air in primary experiments.

Lithium Niobate (LN) crystal has excellent piezoelectric properties, it can be used as substrates of surface acoustic wave (SAW) devices, for example delay line, filter, oscillator, convolver and so on. Intrinsic SAW velocity is determined by the internal property of crystals. In this paper, SAW acoustic basic equation group and SAW mechanical boundary condition equation group are deduced. Intrinsic SAW velocities are calculated systematically using a circle iterative method in zx, xy and yz three coordinate planes of LN along different directions. Stiffness coefficient of piezoelectric crystal can be changed by piezoelectric effect and it is named as piezoelectric modified stiffness coefficient. Reciprocal velocity Curves of LN in the three coordinate planes using the non-modified stiffness coefficients and the modified stiffness coefficients are drawn. Many characters of the SAW device are related to the acoustic velocities, so research results lay a solid base for design and manufacture of the SAW device. It has theoretical significance and practical value.

A cut direction, rotated ZY cut of Lithium Niobate (LN), is studied. LN is a good piezoelectric crystal and it can be used as substrate of surface acoustic wave devices. In this paper, surface acoustic wave equations, including basic equations and boundary condition equations, are deduced. According to these equations the surface acoustic wave velocities are systematically calculated using a circle iterative method for LN along different directions in optimum decoupling acoustic sagittal YZ plane. The electromechanical coupling coefficients for rotated ZY cut LN are also calculated. The optimum cut direction of the LN crystal piece as substrate of surface acoustic wave devices is determined by the largest electromechanical coupling coefficient.

A co-axial transmission elastic-backscattered lidar aiming to detect the optical properties of the clouds is presented in this paper. The modular co-axial design can guarantee the consistency of the transmitting part and the receiving part. In practice a specific diaphragm is used to suppress the stray light of the primary mirror and background light to improve SNR of the backscattered signal in the daytime. So the near ground signal must be corrected with the appropriate overlap factor. A Licel transient recorder is used for data acquisition in analog and photon counting combined in one acquisition system. With the 15 MHz sampling rate, the spatial resolution of 10 m can be attained. The control over the transient recorder and the treatment of the data is performed on a PC. After getting the correctional backscattered signal, retrieving and analyzing the extinction coefficient profile, the cloud base, cloud peak and related optical parameters of the clouds can be confirmed. In order to testify the feasibility of our lidar, it was implemented with a Finland ceilometer Vaisala simultaneously in May in 2008 in Hefei. Results show the lidar system is stable and the data is reliable.

Zn_0.9Co_0.1O bulks were prepared by solid state reaction at various fritting temperatures in order to investigate the structural and optical properties of the bulks. The valence electron and doping concentration in bulk was measured by Xray photoelectron spectroscopy (XPS) instrument. Some basic properties of the bulk material in powder were examined to enhance the comprehension of magnetism in these semiconductors. The corresponding magnetic properties were evaluated by field-cooling and zero-field-cooling magnetization measurements, while the optical properties were tested by Fourier transformed infrared spectrum (FTIR). It is indcated that Co ions are well inserted in the ZnO structure and surrounded by four oxygen. It means that a series of Co have substituted Zn and the sample all the same maintains original wurtzite structure in lattice with a sintered temperature of 1200 °C, then it leads to chemical bond formation of Co-O. Furthermore, the fritting temperature do not play a crucial role in the determination of Co content.

To improve the accuracy of image motion measurement for panoramic aerial cameras, the paper proposed a method of real-time image motion measurement based on 2D spatial correlation. An auxiliary area CCD is positioned paralleled to the main linear TDI CCD in the focal plane of the camera. For every frame of the image sequence taken by the auxiliary CCD, a prediction on the displacement of the current image in the flight direction is made based on the forward image motion velocity. The current and the reference images are combined together for 2D-correlation, which products an image motion vector. By decomposing the vector, both the forward and pendulum-swing image motions can be determined. The demanding computational requirements for the real-time 2D-correlation are covered by a joint transform optical correlator. Simulation test results show that the accuracy is improved and the measurement error is within 0.2 pixels for input images with SNR=1 dB.

How CCD camera causes vertical blooming was investigated. The technique based on vertical driving timing, which can clear vertical blooming up the high-intensity pixels, was presented. The saturated charge of photo diode, which is produced by high-intensity-pixel during the exposure time of a line, enters the vertical shift register. On the control of CCD vertical driving timing, all pixels of the same column add the saturation charge, and then the image has vertical blooming. The vertical blooming up the high-intensity-pixel is produced by the saturation charge of the last frame. Depended on the control method of charge transfer, a special driving timing, which can transfer the remaining charge, is used for clearing the vertical blooming up the high-intensity-pixel. The driving timing is tested on a CCD demo board of ICX205, and the testing showed that the vertical blooming up the high-intensity-pixel is deleted. This method has been applied to intelligent traffic monitoring.

The signal-to-noise ratio of the charge coupled devices (CCD) output can be improved by the optimization of control parameters of correlated double sampling (CDS), however, the control parameters of CDS of high-speed CCD is difficult to determine from experiments. In this paper, an adaptive algorithm is proposed to adjust the control parameters of CDS. With fixed target and exposure parameters, the CDS control parameters such as the width of reset pulse, the timing of noise sampling and data sampling are tuned. The images on all combination of the CDS control parameters are acquired. The square sum of the Tenengrad function of all pixels on each image is used to evaluate the quality of the image. The combination of the three CDS parameters corresponding to the maximum sum is chosen as the CDS control parameters, and then the signal-to-noise ratio of the CCD out is the best. Finally, the algorithm is implemented in FPGA and the experiments results show that, compared with the best image acquired without adaptive algorithm, the parameters of edge profile improved from 507.4 to 763.8, the parameters of MTF50 improved from 526.5 to 937.8.

A liquid crystal display (LCD) recently comes into common use. It is possible for this display unit to provide the same size of displaying area as the image screen on the panel. Thus the conventional display can show only one screen, but it is impossible to enlarge the size of a screen, for example twice. To enlarge the display area, the authors have developed an enlarging method of display area using a mirror. Our extension method enables the observers to show the virtual image plane and to enlarge a screen area twice. In the developed display unit, we made use of an image separating technique using polarized glasses, a parallax barrier or a lenticular lens screen for 3D imaging. The mirror can generate the virtual image plane and it enlarges a screen area only twice. In this paper, we present a new extension method to enlarge a screen area quadruple.

We developed a glasses-free 3D stereoscopic display using an LCD display panel and a special grating film for stereoscopic viewing. The display screen is divided in half in order that left and right regions provide the stereoscopic images for left and right eyes. Because both stereoscopic images are not in the same position, it is difficult for the observer to view the 3D image by the stereoviewing. The grating film can solve this problem because it shifts both left and right images to the same position. Moreover this grating film can give us glassesfree 3D viewing because of its view control effect. As the result, the observer can watch overlapped stereoscopic images for left and right eyes without special glasses such as polarized glasses.

The authors have researched support system of the reminiscence and life review activity. This support system consists of an interactive tabletop display and interface system. On the reminiscence and life review activity, a therapist puts pictures on the table so as to trigger a talk. However some observers may perceive upside down images if they sit down opposite the therapist. To overcome this problem, we have developed the display system which can be viewed from any direction. In this paper, we propose a 4-views tabletop flat display system for cooperative activity on a round table.

The human vision system has visual functions for viewing 3D images with a correct depth. These functions are called accommodation, vergence and binocular stereopsis. Most 3D display system utilizes binocular stereopsis. The authors have developed a monocular 3D vision system with accommodation mechanism, which is useful function for perceiving depth. This vision unit needs an image shift optics for generating monocular parallax images. But conventional image shift mechanism is heavy because of its linear actuator system. To improve this problem, we developed a light-weight 3D vision unit for presenting monocular stereoscopic images using a polypyrrole linear actuator.

9,10-Diphenylanthracene (DPA) nanocrystals were prepared using a reprecipitation method. Morphologies and Optical properties of DPA nanocrystals were investigated by a scanning electron microscope (SEM), UV-Visible absorption and fluorescence emission spectra, respectively. The results showed that a large amount of DPA nanocrystals form and have a width of about 300-500 nm, a length of 500 nm, a thickness of a few tens of nanometers. Optical properties of the nanocrystals are obviously different from those of DPA monomer. All absorption peaks for DPA nanocrystals experience a bathochromic shift with respect to those of DPA monomer due to the formation of J-aggregates in the nanocrystals. The emission peaks of DPA nanocrystals are red-shifted compared with those of the diluted solution, which are attributed to the intermolecular force difference between the monomer and nanocrystals. In addition, the mechanisms of nanocrystals formation were also analyzed and discussed in detail.

Stereo matching is the process of finding corresponding points in two or more images. The description of interest points is a critical aspect of point correspondence which is vital in stereo matching. SIFT descriptor has been proven to be better on the distinctiveness and robustness than other local descriptors. However, SIFT descriptor does not involve color information of feature point which provides powerfully distinguishable feature in matching tasks. Furthermore, in a real scene, image color are affected by various geometric and radiometric factors,such as gamma correction and exposure. These situations are very common in stereo images. For this reason, the color recorded by a camera is not a reliable cue, and the color consistency assumption is no longer valid between stereo images in real scenes. Hence the performance of other SIFT-based stereo matching algorithms can be severely degraded under the radiometric variations. In this paper, we present a new improved SIFT stereo matching algorithms that is invariant to various radiometric variations between left and right images. Unlike other improved SIFT stereo matching algorithms, we explicitly employ the color formation model with the parameters of lighting geometry, illuminant color and camera gamma in SIFT descriptor. Firstly, we transform the input color images to log-chromaticity color space, thus a linear relationship can be established. Then, we use a log-polar histogram to build three color invariance components for SIFT descriptor. So that our improved SIFT descriptor is invariant to lighting geometry, illuminant color and camera gamma changes between left and right images. Then we can match feature points between two images and use SIFT descriptor Euclidean distance as a geometric measure in our data sets to make it further accurate and robust. Experimental results show that our method is superior to other SIFT-based algorithms including conventional stereo matching algorithms under various radiometric changes.

The spectral power distribution of side emission from erbium-doped fibers lateral was measured by an integrating sphere and was evaluated quantitatively. The power of side upconversion is very low and the evidence of the contribution of signal laser to the upconversion is observed. The side spontaneous emission power was much larger than ASE power and nearly saturated at the lower pump power. With increasing Er³⁺ ions concentration, the contribution of signal laser to the green upconversion decreases and the side spontaneous emission are almost same under the strong 100mW pumping. According to the side emission and scattering power and the end output power, the energy budget is tabulated.

Band selection has been widely used in hyperspectral image processing for dimension reduction. In this paper, a recursive SAM-based band selection (RSAM-BBS) method is proposed. Once two initial bands are given, RSAM-BBS is performed in a sequential manner, and at each step the band that can best describe the spectral separation of two hyperspectral signatures is added to the bands already selected until the spectral angle reaches its maximum. In order to demonstrate the utility of the proposed band selection method, an anomaly detection algorithm is developed, which first extracts the anomalous target spectrum from the original image using automatic target detection and classification algorithm (ATDCA), followed by maximum spectral screening (MSS) to estimate the background average spectrum, then implements RSAM-BBS to select bands that participate in the subsequent adaptive cosine estimator (ACE) target detection. As shown in the experimental result on the AVIRIS dataset, less than five bands selected by the RSAM-BBS can achieve comparable detection performance using the full bands.

When the target is several miles away from the ultra-wide field of view (UWFV) infrared warning system, it will be a point target in the infrared image, so there is no the target information of distance, geometry and texture without which it is hard to assess the threat of target accurately. It is very important for the air defense command and decision making to have a correct threat assessment of the aerial target, and at present there are few reports about the aerial target threat assessment of the UWFV infrared warning system. The characteristic of the UWFV infrared image is analyzed. A laser range finder is used to measure the initial distance of each target which will be sent back to the infrared warning system. Together with the target information of initial distance, gray value, course angle and angular altitude, considering the nonlinear characteristic of aerial target threat assessment, the threat assessment method based on RBF neural network is presented for its good self-adaptive and self study ability to solve nonlinear complex problems. After simulation experiment, it is found that this method is available and effective.

To study the fiber-sensor film applied in detecting Organophosphorus pesticide, methyltriethoxysilane was used as precursor, which was doped by FITC- AchE. Consequently, the excellent Acetylcholinesterase biology sensitivity film was prepared. Physics characteristic of the film and sensitivity of Organophosphorus pesticide were researched. In organophosphorus pesticide residue testing, the experimental results indicated that the linear measurement range could reach 10^-7~10^-6 mol/L, moreover the detection limit is 10^-8 mol/L. The sensor could be applied in biological / chemical research, clinical medicine, environmental protection, food inspection, biochemical preventive war field and so on.

IR focal plane arrays typically contain bad pixels. Bad pixels have to be corrected because those can significantly impair the performance of target-detection algorithms. On the other hand, particularly as an aid to visual interpretation, it is desirable to replace the bad pixels. IR image contains spatial information and is correlative in spatial domain. In spatial statistics the semivariogram is an important function that relates semivariance to sampling lag. This function can characterize the spatial dependence of each point on its neighbor and provide a concise and unbiased description of the scale and pattern of spatial variability. One of the main reasons for deriving semivariogram is to use it in the process of estimation. Kriging is an interpolation and estimation technique that considers both the distance and the degree of variation between known data points when estimating values in unknown areas. In this paper a new technique based on spatial statistics is developed for bad pixel replacement. The main objective of the technique is to replace bad pixels through Kriging estimation. Theory analysis and experiments show that the method is reasonable and efficient.

The p-n junctions in planar detectors are usually formed by diffusion of p-type impurity, and the effect of diffusion is crucial for device performance. This work reports the investigation of cross-sectional scanning capacitance microscopy (SCM) on the p-type diffusion in device structures of planar InGaAs/InP infrared detectors. Compare to other methods, SCM can provide 2-dimensional carrier distribution mapping with nanometer resolution, thus it meets the requirement of the measurement on micrometer sized photosensitive elements. This work covers two types of InGaAs/InP device structures: i.e. the avalanche photodiodes (APD) and the PIN near-infrared detectors. For APD structures, we obtain the 2-dimensional carrier distribution and vertical p-type depth under 3 diffusion conditions. For PIN near-infrared detectors, the SCM image provides the diffused p-n junction both on the vertical and lateral direction. A stronger lateral diffusion around the InGaAs/InP heterojunction is observed, which indicates the influence of InGaAs/InP boundary on the vertical diffusion. And the junction region can be detected distinctly from the SCM profile, exhibiting the nanometer scale resolution. Finally, the ratio of lateral to vertical Zn diffusion distance in InP is acquired as 0.67. Our results demonstrate the distinctive capability of SCM investigation on semiconductor optoelectronic device structures.

We designed a new spectral bidirectional reflection distribution function (BRDF) measurement instrument, which can be utilized to measure isotropic materials simply in laboratory. The measurement instrument consists of a fiber optic spectrometer, a three-dimensional turntable, a halogen light source and a computer. The spectrometer acquires 696 samples in visible band. The angular range controlled by three-dimensional turntable is 0~330° and 0~80° for azimuth angle and zenith angle respectively. The halogen light source supplies a continuous spectrum with high efficiency and stability in the wavelength range from 360~1500 nm. The spectrometer and the three-dimensional turntable connect with the computer. The angle rotation and data acquisition are all controlled by the computer. The spectral BRDF measurement of three materials is conducted. The relation of spectral BRDF, wavelength and reflected zenith angle is presented. In conclusion, the designed spectral BRDF measurement system can acquire spectral BRDF data quickly and accurately, thus it is an efficient way to measure material spectral reflected properties which is need for computer rendering, target identification.

Using a buffer layer between C₆₀ and cathode was an important and popular approach to improve the performance of organic photovoltaic cells. In this work, we chose CuPc (Copper(II) phthalocyanine) as an electron donor material, C₆₀ (fullerene) as an electron acceptor material and BCP (Bathocuproine) as an exciton blocking layer to fabricate an organic solar cells with a structure of ITO/CuPc/C₆₀/BCP/Ag, and studied the relationship between the photoelectric properties of organic solar cells and the film thickness of BCP. The results showed that the power conversion efficiency (PCE) was closely related to the thickness of exciton blocking layer. With the increasing of BCP film thickness, the power conversion efficiency of the device increased first and then decreased. When the thickness was 0 nm, the power conversion efficiency (PCE) was 0.357 %. When the film thickness was 25 nm, the PCE was 1.013 %. And when the thickness was 50 nm, the PCE was 0.43 %. However, when the thickness was 100 nm, the PCE was 0 %.We presumed that the exciton blocking layer reduce the quenching rate at the interface between organic layer and cathode so that exciton can be separated into electrons and holes more effectively. As a result, the PCE increased. At the same time, if the film of BCP layer thickness is too thick, PCE would sharply decrease due to high resistance during collecting charge carriers.

In this paper, the buffer interlayer was formed by first depositing a pure nickel layer on the p-type Si (100) substrate, and then the boron nitride thin films were deposited by using radio frequency magnetron sputter. We used the purity of 99.99 % nickel and purity of 99.99 % boron nitride (h-BN) as targets in the experiment. Step profiler has been employed to measure the thickness of nickel interlayer and cubic boron nitride thin films. Fourier transformed infrared spectroscopy (FTIR) has been employed to characterize boron nitride thin films. The content of cubic phase boron nitride in the films has been calculated through the FTIR spectra. The surface morphology and the grain size of films were examined using an atomic force microscope (AFM). The mixture gas of argon and nitrogen was as the working gas in our experiment. To study the thickness of nickel interlayer how to influence the formation of cubic phase in the boron nitride thin film, we changed the thickness of nickel interlayer by controlling the sputtering time with the same substrate temperature, working gas pressure and other conditions. The results showed that the thickness of nickel interlayer is the key factor in the formation of cubic boron nitride. The growth of cubic boron nitride at room temperature can be realized by appropriately selecting the thickness of nickel interlayer. We also drew out when the thickness of nickel interlayer was about 150nm, the content of cubic phase in boron nitride thin films would get up to the highest. On this basis of these results, we also examined impacts of the substrate temperature (100~400 °C), substrate bias (50~210 V) and annealing conditions on the formation of the cubic boron nitride thin films.

Laser radar is rapidly developing towards very capable sensors for number of applications such as military sensing and guidance, auto collision avoidance, robotic vision and atmospheric sensing. In this paper, the detection performance of non-scanned Laser Rang-gated (LRG) imaging system is studied. In order to compute the detection range of laser active imaging system, the range equation is derived by using laser illuminating model and considering factors which affect system imaging quality. According to the principle of laser radar and the characters of objects and the detectors in special applied setting, it mainly deduced the non-scanned laser radar range equation of the range-gated system, meanwhile, the SNR model of non-scanned LRG imaging system is set up. Then, relationship of the detection probability, the false alarm probability and the signal-to-noise ratio in the non-scanned LRG imaging system are analyzed, the influence factors of system's performance are pointed out, and the solution is proposed. The detection performance simulation software of non-scanned LRG imaging system is designed with MATLAB and the performance of the imaging system is simulated.

Polyaniline/carbon nanotubes (PANI/CNTs) nanocomposite thin films were fabricated through an in-situ self-assembled method on the interdigitated electrodes for ammonia (NH₃) gas sensors. CNTs presented in this work consisted of singlewalled CNTs (SWNT) and multi-walled CNTs (MWNT). The pure MWNT dispersed in N,N-Dimethyl Formamide (DMF) solution was also dipped on the interdigitated electrodes for gas-sensing property comparison. The SEM images showed clearly that PANI/CNTs nanocomposite thin films possess a nanofiber mesh like structure, and TEM analysis exhibited that the diameter of the pure MWNT was 10 nm whereas that of the PANI/MWNT nanofiber was about 50 nm, which confirmed a PANI layer packed on the surface of MWNT during the in-situ polymerization process. The gasresponse of different sensing films to NH3 was investigated at room temperature. It was found that PANI/MWNT nanocomposite thin film exhibited the higher sensitivity than pure MWNT film and PANI/SWNT thin film, which might be ascribed to more active sites for gas adsorption for the PANI/MWNT nanocomposite thin film. The response-recovery property was studied when the PANI/MWNT thin film sensor was exposed to different concentrations of NH₃ ranging from 23 to 141 ppm, and it was found that the sensitivity was linear to the concentrations of NH₃. This sensor also had good reproducibility and selectivity.

A continuous zoom optical system with finite conjugate distance was designed for low-vision aid device. The configuration of the zoom optical system and the evaluation of the optical performance including modulation transfer function(MTF) and diffuse spot in diameter were investigated. The stability of the system performance was forecast by using the tolerance sensitivity analysis and Monte Carlo method. This mechanically compensated zoom lens combines four group components including a fixed objective, moving variator and compensator, and a fixed eyepiece with a total of 10 pieces of lens. The optical system which has a tube length of 76 mm and a front intercept distance of 262 mm can realize continuous zoom from 8.8~ 52 mm and 9.3 X zoom ratio without any image vignetting or obvious fluctuation in image quality.

Optical tracking systems need to measure the shift of target in real time so as to compensate the shift effect. For extended target, template matching techniques are usually used to estimate the image shift, in which the shift can be computed up to subpixel with the parabolic interpolation. In this paper, we propose a new method to estimate the shift accurately building on geometric feature point tracking. The method first extracts feature points from the reference image using Harris detector, and tracks the same feature point by correlating the small patch around it with that of each point detected in other images. The subpixel feature point position utilized to estimate the image shift is then determined by the modified Harris strength of the pixels around that point. Experimental results validates that the proposed method can accurately measure image shifts over large distance under noisy conditions, and that the mean of estimate error is less than 0.03 pixels. Moreover, the contrast of long exposure images before and after shift compensation is compared to evaluate our algorithm in the optical tracking system.

With developments in uncooled infrared plane array (UFPA) technology, many new advanced uncooled infrared sensors are used in defensive weapons, scientific research, industry and commercial applications. A major difference in imaging techniques between infrared IRFPA imaging system and a visible CCD camera is that, IRFPA need nonuniformity correction and dead pixel compensation, we usually called it infrared image pre-processing. Two-point or multi-point correction algorithms based on calibration commonly used may correct the non-uniformity of IRFPAs, but they are limited by pixel linearity and instability. Therefore, adaptive non-uniformity correction techniques are developed. Two of these adaptive non-uniformity correction algorithms are mostly discussed, one is based on temporal high-pass filter, and another is based on neural network. In this paper, a new NUC algorithm based on improved neural networks is introduced, and involves the compare result between improved neural networks and other adaptive correction techniques. A lot of different will discussed in different angle, like correction effects, calculation efficiency, hardware implementation and so on. According to the result and discussion, it could be concluding that the adaptive algorithm offers improved performance compared to traditional calibration mode techniques. This new algorithm not only provides better sensitivity, but also increases the system dynamic range. As the sensor application expended, it will be very useful in future infrared imaging systems.

This paper describes a 3D laser scanner for dental cast that realize non-contact deepness measuring. The scanner and the control PC make up of a 3D scan system, accomplish the real time digital of dental cast. Owing to the complexity shape of the dental cast and the random nature of scanned points, the detected feature curves are generally not smooth or not accurate enough for subsequent application. The purpose of this p is to present an algorithm for enhancing the useful points and eliminating the noises. So an image enhancement algorithm based on wavelet transform and fuzzy set theory is presented. Firstly, the multi-scale wavelet transform is adopted to decompose the input image, which extracts the characteristic of multi-scale of the image. Secondly, wavelet threshold is used for image de-noising, and then the traditional fuzzy set theory is improved and applied to enhance the low frequency wavelet coefficients and the high frequency wavelet coefficients of different directions of each scale. Finally, the inverse wavelet transform is applied to synthesis image. A group of experimental results demonstrate that the proposed algorithm is effective for the dental cast image de-noising and enhancement, the edge of the enhanced image is distinct which is good for the subsequent image processing.

Rare earth organic complexes possess characteristic luminescent properties, such as extremely sharp emission bands, long lifetime and potential high internal quantum efficiency. The corresponding nano-materials have attracted extensive attention recently owing to the potential application for OLED and photovoltaic devices. In this report, ternary complex of rare earth Tb(acac)₂AA (acac= acetyl acetone, AA= acrylic acid ) uniform nanorods have been prepared by sonication. The properties of Tb(acac)₂AA nanorods were characterized by X-ray diffraction (XRD), Fourier transform Infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). It is interesting to observe that the nanoparticles with diameter of 300 nm are growing into the nanorods with size of 80×1200 nm (W×L) with the increasing of the power output. It can be explained that the cavitation effect was increased with the increasing power output and thus accelerated the growth of nanorods from nanometer-sized seed on the Tb(acac)₂AA nanoparticles. Furthermore, the size of the nanorods is much smaller than that of the bulk prepared by precipitation. The luminescent properties of Tb(acac)₂AA nanorods were studied in comparison with that of the bulk. The results indicated that the line shapes of corresponding luminescent spectras are similar, but the luminescent intensity of the nanorods is two times stronger than that of the bulk. It means that the nanorods have higher fluorescence quantum efficiency than the bulk. In addition, the fluorescence lifetime of the nanorods is obviously longer. In summary, sonication is an effective approach to prepare rare earth nanomaterial with high luminescence efficiency.

Accurate harvesting depends on the order of the accuracy of 3D location for harvesting robot. The precision of location is lower when the distance between fruit and camera is larger than 0.8 m for the method based on binocular stereo vision. This is a big problem. In order to improve the precision of depth measurement for ripe tomato, two stereo matching methods were analyzed comparatively which were centroid-based matching and area-based matching. Their performances in depth measurement were also compared. Experiments showed that the relationship between distance and measurement was linear. Then, models of unitary linear regression (ULR) were used to improve the results of depth measurement. After correction by these models, the depth errors were in a range of -28 mm to 25 mm for centroid-based matching method and -8 mm to 15 mm for area-based matching method at a distance of 0.6 m to 1.15 m. It can be concluded that costs of computation can be decreased with the promise of good precision when the parallax of centroid which is acquired through centroid-based matching method is used to set the range of parallax for area-based matching method.

The tongue coating diagnosis is an important part in tongue diagnosis of traditional Chinese medicine (TCM).The change of the thickness and color of the tongue coating can reflect the pathological state for the patient. By observing the tongue coating, a Chinese doctor can determine the nature or severity of disease. Because some limitations existed in the tongue diagnosis method of TCM and the method based on the digital image processing, a novel tongue coating analyzer(TCA) based on the concave grating monochrometer and virtual instrument is developed in this paper. This analyzer consists of the light source system, check cavity, optical fiber probe, concave grating monochrometer, spectrum detector system based on CCD and data acquisition (DAQ) card, signal processing circuit system, computer and data analysis software based on LabVIEW, etc. Experimental results show that the novel TCA's spectral range can reach 300-1000 nm, its wavelength resolution can reach 1nm, and this TCA uses the back-split-light technology and multi-channel parallel analysis. Compared with the TCA based on the image processing technology, this TCA has many advantages, such as, compact volume, simpler algorithm, faster processing speed, higher accuracy, cheaper cost and real-time handle data and display the result, etc. Therefore, it has the greatly potential values in the fields of the tongue coating diagnosis for TCM.

The thermo-resistance effect in silicon has been exploited for the fabrication of uncooled infrared detectors. In this paper, based on the Schrodinger equation of material radiation system and the micro-structure of silicon, the infrared absorption theory of silicon is analyzed. The results show that the infrared activity of amorphous silicon is more activate than crystalline silicon because of the fault and long range disorder, and using the impurity B, Li, and H, the infrared activity of silicon also will be activated.

A wet chemical etching method for (211)Si substrates was demonstrated in this paper. The morphologies and cleanness of (211) Si surface etched in different mixture ratio HF-HNO₃-HAC solutions have been studied by using optical microscope and the surface profile measuring system (SPMS). The analysis of the surface images indicated that the Si etched by the HF-HNO₃-HAC (2:15:5) has the smoother surface, and the wet chemical etching can effectively eliminate the damage introduced by the chemo-mechanical polishing. An auto wet chemical etching agitator which can move in the vertical orientation was used. The wet chemical etching rate of (211) Si was obtained in the room temperature and the transmitted spectra of (211) Si with different thickness were measured by Fourier Transform Infrared Spectroscopy (FTIR) and compared. It is confirmed that the Si with different thickness make no difference to the spectral response in mid-wave. By using this novel technology, the Si substrate of HgCdTe/Si detector was removed completely with the HF-HNO₃- HAC (2:15:5) solution. It is obvious that the wet chemical etching method can remove the (211) Si substrates with no damage and detector can work better.

Image intensifier is the kernel of low-light-level device. The field flaw is one of the important index parameters of the image intensifier. Traditionally the statistic number of the image intensifier's field flaws is calculated through the people's eyes by the aid of an optical microscope, which main limitation is subjective and inefficient. With the broad application of the high-powered CCD and digital imaging processing method in testing performance of image intensifier, the method of appraising SNR based on spatio-temporal noise theory can accurately reflect the spatio-temporal heterogeneous of fluorescence's output image and fulfill the requirements of digital and automatic test. The limitation of the flaws' shape and position can be disregard and the accurate flaws' inspection can be realized rapidly by this method. In this paper, the main factors of forming the field flaws are analyzed and the mathematic model of spatio-temporal SNR is deduced. The hardware devices of the test system for image intensifier's spatio-temporal SNR are discussed. The spatio-temporal SNR of Gen image intensifier is tested by this test system and the test software based on Visual C++ and Matlab. The digital and automatic test of a factitious field flaw is realized by the theory of spatio-temporal SNR. The test precision can achieve pixel level. The experimental results show that this new method is rational, reliable and visualized.

The primary compact high resolution imaging spectrometer was developed and reported. Due to its numerous wave bands the original image data is always in a huge scale and costs a tremendous process overhead, but the data amount of the region of interest is as a rule in the order of thousandth, if not less, of that of the whole push-broom region. With a digital micromirror device (DMD), only the region of interesting object is imaged by the imaging spectrometer, which results in a distinct reduction of data quantity and a high data compression ratio. A DMD of high turning rate and residential time adjustability is used as a spatial light modulator to fulfill the object selection function. It is placed after the fore objective and able to reflect the object to either the panchromatic CCD camera channel or the imaging spectrometer channel. The position of the object can be firstly determined through the image interpretation from panchromatic imaging channel and a DMD control command is executed to switch the corresponding mirrors to the imaging spectrometer channel, thus only the object region of interest is imaged by the spectrometer. The multiple objects of both printed patterns and real leaves are accurately determined and selected according to their different locality and shape features. The panchromatic and hyperspectral image data are both collected for further effective object recognition.

White organic lighting-diode (WOLED) can be used as flat light sources, backlights for liquid crystal displays and full color displays. Recently, a research mainstream of white OLED is to develop the novel materials and optimize the structure of devices. In this work a WOLED with a structure of ITO/NPB/PAA/Alq₃: x% rubrene/Alq₃/Mg: Ag, was fabricated. The device has two light-emitting layers. NPB is used as a hole transport layer, PAA as a blue emitting layer, Alq₃: rubrene host-guest system as a yellow emitting layer, and Alq₃ close to the cathode as an electron transport layer. In the experiment, the doping concentration of rubrene was optimized. WOLED 1 with 4% rubrene achieved a maximum luminous efficiency of 1.80 lm/W, a maximum luminance of 3926 cd/m² and CIE coordinates of (0.374, 0.341) .WOLED 2 with 2% rubrene achieved a maximum luminous efficiency of 0.65 lm/W, a maximum luminance of 7495cd/m² and CIE coordinates of (0.365,0.365).

A novel spectrum measuring system, which was based on the embedded system of ARM, controlled by a PC was developed. The system is composed of a monochromator, a high-precision voltage amplifier, an ARM7 system and a PC. The monochromator convert optical signal into electronic signal, and the signal is then amplified by the voltage amplifier. Then the amplified signal is converted to digital signal by the ARM7 system. At the end, the digital is send to the PC by the USB interface. After the processing and analyzing of the data, PC can measure and display the spectrum of the light source real-time. The system can measure the spectrum and chromaticity coordinates of light source and display device with high precision, and has a friendly interface.

The advantages and disadvantages of conventional image quality evaluation methods are analyzed and according to the characteristics of laser disturbing image, an image quality evaluation method which is based on wavelet weight and correlation is established. In the method, both the original and disturbed images are processed by wavelet decomposition, replacement and reconstruction. Then different sub-band images are obtained and their correlations are calculated. Combined with band-pass characteristic of human vision, visual weighted coefficients are obtained and objective calculation results are output finally. Experimental results show that this method not only can overcome the influences of different conditions on evaluation of laser disturbing effect, but it is also in good agreement with the subjective method.

In this paper, we design a structure of CsI(Tl) thin film crystal cell, and cover the CsI(Tl) thin film on the surface of the CCD directly. In order to prevent the photons emit from the surface of film, which result in depressing the fluorescence efficient, we cover the film with alumina to form reflective layer. Al layer is used to separate the CsI(Tl) crystal according to the size of CCD photosensitive cell, which solve problem that fluorescence cross talk between the different photosensitive cell. The fluorescence transmission efficiency of CsI(Tl) film crystal cell model is also researched , the results show the fluorescence transmission efficiency is maximum when the thickness of film is 40 μm.

Interference hyper spectral image and the images contain some interference information which are collected by the LASIS are only middle results of the spectrometer, is a three-dimensional image. The amount of the data is large size, and need to be compressed. For testing the actual interference hyper spectral image, use different composed way, to compose of LAMIS and LADIS image, the LASIS image has different target with different spectral band, LAMIS has the same target with different spectrum, LADIS has the same spectrum with different target . The spatial correlation and spectral correlation are analyzed. The self-coefficient and cross-coefficient are also calculated. The method that LASIS extract into LADIS is proposed, which separate interference information form spatial image, and it is a new foundation for interference information protection of LASIS image. The feather of LASIS image is revealed, the results obtained can be use LASIS image processing and compressing.

A photoresist film was applied on the indium tin oxide (ITO) conductive glass which was coated with silver. The photoinduced changes of the photoresist film were achieved by exposure to UV lamp through a grating & lead pattern photomask. The photoresist film exhibited grating lines and lead patterns after development. The Ag-ITO double film coated with photoresist patterns was etched to double-layer electrode patterns by ion beam. After photoresists were stripped, silver grating electrodes were removed and ITO grating electrodes were coated with polyimide (PI) and treated by rubbing. The orientation was perpendicular to grating. The back electrode was a piece of ITO glass which was oriented by the same method. Nematic liquid crystal (LC) was injected into the grating cell. Other silver-leads were retained and connected with driver ICs and flex circuits. The binary optic liquid crystal blazed grating was fabricated. Step-shaped phase was obtained by applying a step-shaped voltage on LC grating electrodes. It formed blazed grating at one order and the diffraction angle can be shifted dynamically. The sample was checked up by the optical microscope and the He-Ne laser. The results indicate that the sample had clear grating structure and every grating electrode can be controlled separately. The range of the first order of diffraction angle was ±6° in theory. The diffraction efficiency decreased as the diffraction angle increased, and the maximum diffraction efficiency can exceed 80 %.

Cd_1-xZn_xS ternary material has a wider band gap than CdS which makes it a better window material for use in CdTe solar cells. Typical chemical bath deposition (CBD) processes for sulfides employ an alkaline medium containing the chalcogenide source and the metal ion. In this work, Cd_1-xZn_xS thin films have been deposited from acidic solution. The composition, surface morphology and structural properties of the as-deposited and annealed Cd_1-xZn_xS thin films were studied using energy dispersive X-ray analysis (EDX), scanning electron microscopy (SEM) and X-ray diffraction (XRD) techniques. The band gap of the as-deposited Cd_1-xZn_xS thin films varied from 2.38 to 2.44 eV, whereas in the annealed films varied from 2.36 to 2.42 eV. The decreased band gaps of the Cd_1-xZn_xS thin films were due to the improved crystalline nature of the material.

The Liou's model eye is close to anatomical, biometric and optical realities, and is effective in predicting the optical performance. An efficient approach for designing of ophthalmic lenses by regarding ophthalmic lens and Liou's model eye as a single optical system, based on optimization of aspherical surface coefficients is presented. The wavefront aberration and diopter are taken into consideration, the traditional damped least-squares methods are chosen with the high order aspherical equations being used. The appearance of the lens designed is improved obviously than the spherical ones and the fabricating is not complicated; the optical performances are controlled in an acceptable range. With the help of the structure parameters of a single eye ball obtained, custom-design ophthalmic lens is workable which might be a direction of lens design in the future.

In this work structural composition and fabrication process of cathode for transparent OLED were investigated. Using a LiF/Al/Ag/Alq₃ semitransparent cathode and a Mg:Ag/ITO cathode, green fluorescent transparent organic light-emitting devices (TOLEDs) were fabricated. ITO was evaporated as a cathode onto a thin Mg:Ag layer by DC magnetron sputtering method with the assistance of tiny H₂O vapor during deposition process. The fabrication of LiF/Al/Ag/Alq₃ electrode was processed without breaking the vacuum. At a bias of 15 V, the luminance of the TOLED with Mg:Ag/ITO and LiF/Al/Ag/Alq₃ cathode were 3016 and 4535 cd/m², respectively. The results indicate that LiF/Al/Ag/Alq₃ electrode can be used as an effective and stable cathode in TOLEDs.

The conventional display can show only one screen, but it is impossible to enlarge the size of a screen, for example twice. A mirror makes another world in the silver coated glass. The authors have ever presented an enlarging method of display area using a mirror. Our extension method enables the observers to show the virtual image plane and to enlarge a screen area twice. To provide twice enlarged region, the surface of a visual display needs to produce dual views. Although the displaying region is doubled, this virtual display could not produce 3D images. To solve this problem, we must prepare to generate four views; side by side observing view windows enable us to perceive stereoscopic 3D images and a vertical neighbor viewing window makes dual views for enlarging display area. In this paper, we propose a 3D imaging display with horizontal and vertical parallaxes using an angle-controlled unidirectional 4-views display.

This paper focuses on the study and experiment of vision control system for an inverted pendulum. To solve some key technical problems, the hardware platform and the software flow of the control system have been designed. The whole control system is composed of vision module and motion control module. The vision module is based on "CCD camera", the motion control module is based on "Motion Control Card, Servo Driver and Servo Motor", and the software is based on LabView. The main research contents and contributions of this paper are summarized as follows: (1) Analyze the functional requirements of the vision control system about the inverted pendulum, developing the hardware platform and planning the overall arrangement of the system; (2) Design the image processing flow and the recognition track process of the moving objects. The accurate position of the pendulum can be obtained from the image through the flow, which concludes image pretreatment, image segmentation and image post-processing; (3) Design the software structure of the control system and write the program code. It is convenient to update and maintain the control software due to the modularity of the system. Some key technical problems in the software have been solved, so the flexibility and reliability of the control system are improved; (4) Build the experimental platform and set the key parameters of the vision control system through experiments. It is proved that the chosen scheme of this paper is feasible. The experiment provides the basis for the development and application of the whole control system.

The traditional immobilized biomolecule detection technique on arrays has been fluorescence, but this has limitations because of its reliance on fluorophores. Alternatively, many label-free detection techniques have been developed such as surface plasmon resonance (SPR), ellipsometry, thin-film interference, diffractometry, and waveguides. These techniques have the advantage of high speed and high sensitivity, but in exchange rely on complicated structures or detailed sensing cells. A novel reflectivity-difference biosensor is introduced in this paper. When the sensor covered with a protein layer, the cells and the land would have opposite changes of the reflectance which lead to intensity shifts at the far-field diffraction plane. Therefore, it is convenient for the operation without intricate sensor structures and multifarious optical systems.