This PDF file contains the front matter associated with SPIE Proceedings Volume 10838, including the Title Page, Copyright information, Table of Contents, Author and Conference Committee lists.

Freeform optics are lenses or mirrors with surfaces having no rotational symmetry. They were conceived more than a century ago, but have recently received new attention for solving design problems. The special methods needed to manufacture them have included direct cam driven or digital grinding or milling, hot glass sagging, casting, injection molding, and fast-tool diamond turning. More recently, precision 3D printing and nanocrystalline powder compression molding have offered promising new capabilities for inexpensive high-volume commercial production in the future. Applications of freeform optics have included progressive spectacle lenses, focus adjusting devices, and aperture phase masks for special purposes. These design applications and manufacturing capabilities have been related to each other in interesting ways, and will be illustrated through a selection of patents and photographs of commercial products.

An ABB IRB6640 industrial robot is used as a processing platform for optical polishing. The relationships of coordinate systems are defined, the algorithm of coordinate transformation, Euler angles and quaternion are provided. M-like removal function and Gaussian-like removal function are used to simulation process an off-axis aspheric surface. The surface error after polishing by M-like removal function is 1.5 to 2.5 times bigger than Gaussian-like removal function. This proves that M-like removal function also has good convergence speed. Then, the pentagram polishing head is used to polish a Φ600mm off-axis paraboloid surface. After 15 cycles, about 120 hours processing, PV converges from 5.8μm to 0.836μm, RMS converges from 1.2μm to 0.054μm, PV and RMS respectively converge 85% and 95%. The experiment shows M-like removal function has good convergence speed.

Head-mounted display (HMD) system is a research hotspot in virtual reality, which has continuous and rapid development in training, medical treatment, aerospace, and entertainment. For the more comfortable immersive experience, the requirements of compact structure, large exit pupil and low F number should be met simultaneously in HMD system. With the use of x-y polynomial surface, an off-axis head-mounted display system with two freeform reflectors is achieved. The HMD system demonstrates a 10 mm exit pupil, a 23°×16° field of view, an f/# number of 3.0 and an eye relief larger than 15 mm. Based on the tolerance analysis of surface figure errors and position location, we present the on-machine measurement and compensation for enhancing machining accuracy, and the frame and mirror integration for high assembling accuracy. Finally, the HMD system was fabricated and the imaging quality was evaluated. In comparison with the results, the effectiveness of the on-machine measurement and compensation are validated, as well as the reliability of tolerance analysis and mechanical structure.

Sub-aperture stitching algorithm is an attractive method for measuring the figure errors of large aperture optics. Measuring large aperture cylindrical surfaces by this method can effectively improve the problems of lacking sampling points, the results of evaluation are not uniform and so on. In this method, several sub-apertures of cylindrical optics will be measured one by one. Then, the relative spatial location relationship is established by the information of overlapping areas, and the sub-apertures are unified under the same coordinate system through coordinate transformation so as to achieve the stitched measurement result of the whole surface. In this process, we need to compensate for the alignment errors of each sub-aperture, but it is easy to fall into local optimum solutions when mechanical position errors are large. Therefore, a sub-aperture stitching algorithm based on particle swarm optimization (PSO) algorithm is proposed in this paper, which uses PSO to optimize the relative position errors. Particle swarm optimization is less likely to become trapped at a locally optimal solution, thus we utilized this method to develop a more robust algorithm. Computer simulation and experiment demonstrate the feasibility and validity of the proposed method.

To obtain high removal rate and low damages in machining of hard and brittle material,an optical fabrication technology based on fixed abrasive diamond pellets(FADPs) elasticity tool(ET) is proposed. In this paper, we focus on improve the removal efficiency and surface quality by optimizing process parameters, which including speed ratios, eccentricity, spindle speed, pressure, diamond granularity and dwell time. Removal function (RF) model of ET is proposed and optimized. Effects of process parameters on the removal efficiency and surface roughness are illustrated by series of simulation and experiments. Experiment results indicate increasing spindle speed can improve removal efficiency and surface roughness. Orthogonal experiment indicates diamond granularity have greatest impact on removal efficiency and surface roughness. In addition, the removal rate 11.26 mm3/min and surface roughness Ra 4.89 nm is obtained by 10 μm and 3 μm of FADPs respectively.

In the continuous polishing process, the deformation caused by the uneven temperature distribution inside the optical element seriously affects the processing accuracy. This article combines domestic and international studies on the heat deformation of optical elements, and the formula for calculating the heat deformation of optical elements is proposed. Based on the Ansys software, the heat deformation of the element is simulated and analyzed, and the accuracy of the formula is verified. The effects of different shapes, materials, thicknesses, temperature difference on the heat deformation of the optical element are analyzed. After the optical element is processed, the temperature surface measurement experiment is performed to obtain the change of the temperature and the surface figure of the optical element in the cooling process, which has guided significance for improving the continuous polishing temperature field.

To overcome the randomness of free abrasive polishing, the abrasive waste, the resulting hydration layer and other issues, this paper presents the characteristic of bound abrasive polishing for fused silica glass in anhydrous environment. A stable sintering process with a fine grooved polishing wheel is developed, which is applied to polish the fused silica glass. Macroscopically, the influence of pressure and rotational speed on the removal rate and surface roughness is explored. Microscopically, the mechanism of material removal, the chemical reaction and the mechanical action produced by the removal process are expounded by using EDS, XRD and FTIR analysis. The removal rate does not follow the Preston formula, temperature rise and the capacity of chip removal on the polishing wheel are the key factors. Furthermore, the experimental results show that the Ce-O-Si bond is formed by CeO₂ abrasive grains and fused silica under the action of normal force. The bond energy is larger than that of fused silica Si-O-Si bond, so the CeO₂ tears away SiO₂ out of the glass surface under the action of shear force.

Fast Axis Servo (FAS) device, also known as Long Stroke Fast Tool Servo (LFTS) device, is a high dynamic response servo module with a frequency response of several tens of Hertz in a millimeter displacement stroke, which is mainly used for high-efficiency machining of Non-Rotationally Symmetric (NRS) surfaces. The development of optical design takes challenge to the manufacturing technology. Based on the principle of free-form surface turning, the accuracy of free-form surface processed by the FAS system is directly affected by its motion accuracy. With the increase of motion frequency and stroke, the error caused by amplitude attenuation and phase lag will be greatly increased. In order to maintain the accuracy of FAS system at high-frequency motion, in this paper, a FAS prototype is designed and manufactured. The power PMAC controller is used to form a control system. The model of the system is identified through open-loop sweep frequency test. And the feed forward and PID feedback servo control algorithm is used. finally, the tracking error of the prototype under 20 Hz frequency and 5 mm stroke sinusoidal motion is measured to be ±1 um, which has achieved good control effect.

The combination process of Magnetorheological finishing (MRF) and Computer controlled optical surfacing(CCOS) are adopted to overcome the drawback of traditional polishing method in final finishing of single-crystal silicon and the deterioration of the surface roughness of single-crystal silicon by Magnetorheological finishing. In order to meet the requirements of single-crystal silicon by magnetorheological finishing, a new magnetorheological finishing fluid is prepared and orthogonal process parameters experiments are designed to optimize the magnetorheological finishing parameters. Through the uniform finishing experiment of MRF and CCOS, the processing sequence conditions of the combined process are obtained. A single-crystal silicon mirror with diameter of 100 mm is finished with several iterations of MRF and CCOS, the surface roughness Ra reaches 0.7 nm which verified the prepared magnetorheological finishing fluid and the optimized parameters satisfied the Finishing requirements of the single-crystal silicon surface. The results prove that the combination of MRF and CCOS process has unique advantages in the final finishing of single-crystal silicon.

Ultrasonic elliptical vibration cutting (UEVC) is attracting much attention in ultra-precision machining of brittle materials as it was found be able to increase the critical depth of cut (d_c) of brittle materials. However, there are few studies on the prediction of dc for UEVC of brittle materials. In this study, a predictive model was developed for the prediction of d_c in microgroove plunge-cutting with respect to several factors, including the distance from transient surface to target surface (DTSTS), the actual undeformed chip thickness (UCT), the critical UCT (t_c) and crack length (C_m). Experiments on plunge-cutting of KDP crystal were conducted. Results showed the predicted d_c matches well with the experimental ones.

Advanced mitigation process (AMP) has been identified as a most effective method to improve the laser induced damage threshold of the fused silica optics used in the large laser facility, and as the most important sub-process HF etching with multi-frequency megasonic agitation plays a decisive role to improve the damage threshold of fused silica. But because of the physical characteristics of megasonic, the etched surface is apt to generate striated haze which not only modulates the optical field, but also reduces the damage threshold significantly. In this paper, the generating mechanism of the striated haze is discussed, and both of the uneven acoustic field distribution and the optics' redeposited substance are recognized as the primary factor resulted this phenomenon, ultimately based on these discussions a slight swing when etching is proposed to eliminate this phenomenon.

To improve the surface quality and laser damage resistance of Potassium Dihydrogen Phosphate (KDP) crystal processed by single point diamond fly-cutting (SPDF) technique, formation and suppression of KDP surface defects are investigated. Firstly, multiple measuring methods have been utilized to characterize KDP surface defects. According to their structure and chemical characters, KDP surface defects were classified into four categories and forming reason of each was analyzed. Based on these analysis results, theoretical model for describing the formation process of KDP surface defects was established and conditions for achieving defects-free KDP surfaces were proposed. Finally, flycutting experiments were carried out to verify the effect of the defects suppression measures. Experiment results indicate that smooth KDP surface with roughness less than 2 nm can be obtained and KDP surface defects can be suppressed effectively by applying the proposed methods.

In this paper, the prism's static imaging relationship and dynamic imaging theory are used to express the influence of the prism on the optical path in an ideal state. At the same time, the influence of manufacturing error and position error of the prism on the optical path is also analyzed and the corresponding action matrix is deduced. The feasibility of using prism deflection to compensate for prism manufacturing error is discussed, which provides a feasible solution to the general problem, and the corresponding theories are illustrated using the right angle prism as an example.

In grinding and polishing of the aspherical and freeform surface, the CCOS technology is widely used. It is a process during which errors can be corrected quantificationally by a small tool that can follow the local curves of the aspherical and freeform surface. It commonly uses constant pressure during polishing, and thus the desired amount of material to be remove depends on the dwell time. This thesis the pressure regulation is introduced into the CCOS polishing system. The pressure can be controlled in real time in the process of processing, and the application of pressure control in CCOS polishing is realized. The main characteristic of this technology is that the desired amount of material to be removed is controlled by both the polishing pressure and the dwell time. Firstly, a mathematical model was established for the variable pressure polishing process. Then the machining efficiency and the influence of pressure error on machining quality are simulated and analyzed. Finally, a material removal experiment that applied sinusoidal pressure was carried out on a K9 material mirror. Results showed that frequency of the measured pressure is the same as that of the ideal sinusoidal polishing pressure. The spatial period of the measured surface profile is the same as that of surface profile obtained by simulation of the sinusoidal polishing process. The surface profile error is within 17%. In this thesis, variable pressure polishing was achieved. Compared with the constant pressure CCOS polishing technology, the variable pressure CCOS polishing technology adds one more degree of freedom to the polishing process. It need have higher requirements for the pressure active control system, such as the output pressure range, response speed and precision. These performance parameters can affect the processing results. Therefore the key to developing the variable pressure CCOS polishing technology is to research the polishing tool, which must have high performance pressure active control system.

The star sensor is used to detect the position of the stars in space. By recognizing and analyzing star maps, satellites or spacecraft can automatically change the direction of movements to realize the navigation function. However, the strong background radiation in the sky during the day results in a low contrast of the star image. This brings great difficulties to star sensors that work on atmospheric platforms observing stars all the time. To overcome the adverse impacts of the stray lights from the sky during the whole day through the atmosphere, a catadioptric all-day star sensor optical system is presented. In comparison to Cassegrain System, the design has a smaller size of aperture of housing. Therefore, it has the advantage of superb suppression of the stray lights caused by external sky background radiation and other factors. By adopting a plane mirror to compress the light path, the size of the system is decreased, realizing a light and miniaturized design. Based on the analysis of the characteristics of sky background radiation and star radiation, the optical system parameters are selected. The system has a focal length of 800mm, an effective aperture of 70mm, and an instantaneous field of view of 2 °. Meanwhile, with a steering mirror, it can observe an area between 40° and 70° airspace at all day. Finally, the results of the analysis show that the optical system spot shape approaches to a circle in the wide spectrum of 800 nm ~ 1700 nm, and the energy of which is close to the Gaussian distribution and highly concentrated. The modulation transfer function curve is close to the diffraction limit with small chromatic aberration of magnification.

The electro-optical tracking system with the capability of target capture and tracking, is typical astronomical observation instruments. In most of the task scenarios, the electro-optical tracking system must finish the azimuth zero calibration at the initial stage. Two methods are usually used for zero calibration: (1) with the aid of the external autonomous north seeking equipment; (2) with the help of the astronomical measurements under clear weather. The former problem is the increased cost for purchasing additional equipment and training operators, while the latter is limited by weather conditions and personnel experience. In this paper, an independent azimuth zero calibration method based on single gyro for electro-optical tracking system is proposed, which introduces a four-position method on the basis of high-precision angle measure sensor and gyro equipped in the system to calibrate azimuth zero point. The all-weather independent azimuth zero calibration is realized, after data sampling and processing. The experimental verification results illustrate the azimuth zero calibration precision is less than 3’ in 4 minutes, meeting the initial zero calibration requirements of electro-optical tracking system.

In classical electro-optical control systems, the double closed-loop control including speed feedback and position feedback is often used to enhance the closed-loop performance. As the system is subject to internal detection delays and external disturbances, the stability and tracking accuracy of system are greatly challenged. MEMS gyroscopes inertial sensor are widely used in electro-optical control systems due to their advantages of light weight, high resonant frequency, and short response time. However, the Analog-to-Digital conversion and self-filtering characteristics of the sensors determine that there is a certain detection delay, and the system also faces the interference caused by the mechanical resonance. To solve this problem, an improved Smith Predictor method based on inertial sensor-MEMS gyroscope is proposed. The original Smith Predictor is only used to eliminate the effect of delay. Base of that, we modify the predictor’s structure and add a branch of disturbance observer to compensate the external disturbance. The control strategy and the formula derivation is given out. The experimental results show that the closed-loop bandwidth of the system’s speed loop are significantly improved, and the method effectively improves the system’s disturbance suppression performance.

The pressure distribution is the most vital to material removal in continuous polishing in which removes the scratches and subsurface damage induced in grinding and lapping. Firstly, the interface response mechanism of the static contact pair is determined by uniaxial compression test. Then, the numerical model of the optics (Φ50mm×5mm ) and polishing lap(Φ80mm×7mm) contact pair is established to acquire the pressure distribution based on elastic contact mechanics. After that,the compression behavior is characterized by the pressure distribution and real contact area (RCA) measured by fujing pressure film. Attempt is made to clarify the figure of optics in continuous polishing.

Grinding wheel wear has always been one of the key factors that affecting the high precision manufacturing of aspheric optical elements. With the increase of hardness and caliber of workpiece, the phenomenon of wheel wear is more serious. In this paper, the grinding wheel wear rule and the influence of surface form accuracy are discussed. Through orthogonal experience, the parameters of nonlinear regression equation about grinding ratio are determined. And the influence model of grinding wheel wear on the surface form accuracy of the workpiece is built according to the geometric relationship between the grinding wheel and the workpiece of surface. Then, the influence of workpiece caliber, the radius of grinding wheel and the arc radius of grinding wheel to the surface form accuracy are discussed. The machining range constraint by typical precision requirements is obtained, and the surface error compensation method based on the prediction of grinding wheel wear is proposed lastly.

Ion beam figuring technology is ultra-high precision optical processing method. This paper introduces the independent FSGJ800-IBF five axis ion beam figuring equipment. According to the requirement of ion beam motion system dynamic performance of complex optical surface ion beam figuring, the design and control scheme of 3-RPS+XY mobile platform based on hybrid mechanism form five axis motion system was finished. Firstly, the radio frequency (RF) ion beam source was use in this machine. The Ion Beam Figuring System with Five-Axis Hybrid Mechanism was introduced especially the 3-RPS parallel mechanism. The process of polishing complex optical curved surface by ion beam is analyzed. The most close to the spherical surface processing strategy based on the experiments of high gradient lens was done. The aperture of the lens is 44mm and the R/# is 0.705, after a round of ion beam polishing, surface error of optical components RMS from the initial 0.019 lambda (lambda =632.8nm) converges to 0.006 lambda. The experiments verified the availability of the Five-Axis Hybrid Mechanism for high precision complex optical surface error correction.

The influence of polishing parameters such as particle size, pad material and pressure on the surface roughness of glass optics were investigated and analysed. It reveals that the surface roughness will get worse with increase of the polishing particle size. The surface roughness would remain stable in a certain period of polishing pressure, but get worse with increase of the pressure beyond the period. The surface roughness is getting better when using smooth pitch polishing pad than polyurethane pad with lots of micropores. By optimizing the polishing parameters, the surface roughness of large aperture fused silica window is improved to 0.46nm before band-pass filtering and 0.084nm after band-pass filtering.

The causes of the system error in null mirror during interferometric testing was analyzed. The system error in null mirror were obtained by turning the tested surface in different angles along their optic axis. The corrective file was loaded into the interferometer measurement, so as to the system error can be removed directly when testing. Therefore, with this technique, the demands on the material, manufacturing, and assembly of null mirror is not so critical, and the test accuracy is improved observably.

Optical system performance is easily affected by various surrounding conditions, especially the precision optical system, such as interferometer, goniometer, are sensitive to temperature fluctuations. Temperature is an important parameter of the air refractive index. Its fluctuation causes unsteady changes in air density and hence index of refraction changes. So the temperature of the detection room must be controlled in reasonable scope. But the heat released from devices, staff members and luminaires is unavoidable. This study calculates fluid field variations induced by temperature, obtains the air density and temperature distribution by Computational Fluid Dynamics (CFD) software, and then the fluctuations of refractive index are calculated from the density field. The optical path difference (OPD) is then given with density changes, also the OPD RMS values are computed. These data can quantify the influence degree of temperature changes and improve optical design.

High-precision inertial accelerometer is mainly used in aviation, aerospace, and military fields. As the core part of high-precision inertial accelerometer, silicon flexible bar has been working in extremely dynamic environment, which would bring in strong impact loads. Hence, the silicon flexible bar always encounters failure due to cracks and fractures caused by the strong impact loads. In this work, we firstly analyzed the dynamic characteristics of silicon flexible bar using Finite Element Method. The main working modes and stress responses of flexible bar under dynamic loads with various frequencies were investigated. Then, the transient impact process of silicon flexible bar was simulated to explore the effect of transient impacting load and period on the stress distribution of silicon part. The stress-strain behavior of silicon flexible bar was analyzed as well. The critical failure acceleration and strength weakness location of silicon flexible bar were finally determined by the impact experiments. The experimental results were compared with simulated ones, which show that: (1) the first-order mode is working mode of flexible bars, which swings up and down around the x-axis. The transient impact load causes bending deformation of flexible bar, which leads to the stress stratification in the z direction and produces a neutral layer where the stress is the smallest. The tensile and compressive stresses are applied in both sides of the neutral layer and the closer to the surface, the greater the stress. (2) The critical failure acceleration of silicon flexible bars is 100g. The root of the flexible bar is the most vulnerable location due to the stress concentration. Under the same impact load, the shorter the loading time, the greater the stress at the root of the bar.

As a new kind of optical imaging technology, polarimetric imaging can be able to identify the target that may be difficult to conventional ones and can reduce the influence of stray and complex environment. It can efficiently increase the detection dimension of the information and increase capability of target imaging and recognition by imaging the polarization properties of the optical wave. The dissertation researches a type of simultaneous polarization imaging optical system with divided aperture. This system is adopted the identification system of polarization and morphological feature, which can improve the ability of space target classification and recognition. It also can be used as a space-based space target imaging system, which can be used for the classification and recognition of space target. Polarization optical system is adopted the structure mode of two-mirror reflecting systems and field correction mirror, pupil division and four zoning registration scheme of array CCD detector. The system technical parameters are F#/12.5, EFL 1500mm, FOV 0.47°. The size of CCD pixel is 12μm×12μm. The system can detect the light of 0°/45°/90° and visible light for 450-850 nm spectrum. It reached the conclusion that optical system imaging quality is close to the diffraction limit at the Nyquist frequency 41.70lp/mm though simulation test, the system can meet the imaging requirements.

Phase diversity technique (PD) is a widely known method to estimate wave-front aberration of optical imaging system and to obtain reconstructed high-resolution image after degradation. However, when detecting weak or low light object in space, Poisson noise, as the main source of noise, has a serious impact on the accuracy of the PD’s two main function. Hence, we firstly propose a modified PD combined with Non-local Means (NLM) algorithm to reduce the sensitivity of PD towards the Poisson noise. The numerical simulations demonstrate that our approach compared with the traditional PD has a significant improvement in terms of both the wave-front residual root-mean-square error (RMS) and the structural similarity index metrics (SSIM). The wave-front residual RMS decreases by approximately 51% across the Poisson noise levels ranging from 24.48 dB to 61.02 dB. The overall decline range of SSIM significantly decreases from 47% to 17%, and the average of SSIM increases from 84% to 91%. The modified PD would be useful in the AO system with active Poisson noise.

The quality of surface machining of glass-ceramic materials determines the performance of optical components. Low surface roughness and surface/subsurface damage in precision grinding is one of the machining conditions for the ultra-smooth surface of glass-ceramic materials. In this paper, the bowl-shaped diamond grinding wheels with different particle size and binding agent were used. First of all, the orthogonal tests of machining parameters such as different feed rates, spindle speed, and grinding depth at high speeds were designed. Secondly, the surface machining quality and stress distribution after grinding was analyzed. At last, the reasonable machining parameters for high-speed grinding of glass-ceramic materials were explored, in order to provide reference and basis for actual machining.

To further increase the laser-induced damage threshold (LIDT) of calcium fluoride (CaF2), combined technique of chemical mechanical polishing (CMP) and acid etching as a function of removal mechanical defect and impurity contamination was investigated. After CMP process, the surface roughness reduced to Ra 0.68nm, the scratch and subsurface defect were mitigated which rise the LIDT to 8.6 J/cm^-2. Due to the acid etching, the surface roughness of CaF2 elements increased to Ra 0.8nm, while the LIDT reached 11 J/cm^-2, benefit from the elimination of impurity contamination. The result laser-induced damage test shows that, comparing to mechanical abrasive polishing (MAP), the LIDT increased by 240% after combined technique, it demonstrated that combined technique is an effective way to improve the resistance of laser damage of CaF2.

The laser scanning interference method requires the optical frequency emitted by the tunable laser be ideally linear with time. However, the laser is affected by the mechanical control precision and the influence of carriers in the gain medium. It is difficult to meet this requirement. The spectrum of the target spectrum will be widened, leading to a serious decrease in measurement accuracy and resolution. The optical frequency sampling method can eliminate the influence of the time domain nonlinearity of the frequency sweep in principle by sampling the frequency sweeping interferometric signal in the optical frequency domain. However, this method is limited by the Nyquist Sampling Theorem. It requires that the optical path difference of the system's auxiliary interferometer should be at least 2 times of the measuring optical path, which seriously reduces the theoretical measurement range of the frequency sweep interference determined by the coherence length of the laser. In response to this problem, the paper puts forward the phase shift frequency sampling method. When the optical path exceeds 1/2 of the optical path of the auxiliary interferometer, by introducing the phase-shifting factor, the measured signal is shifted according to the phase of the auxiliary interferometer signal, so that the frequency of the measured beat signal after phase-shifting is less than 1/2 of the frequency of the auxiliary beat signal, which satisfies the Nyquist sampling theorem in principle, and breaking through the measurement range limitation based on the frequency sampling method. Through simulation experiments, comparing the traditional frequency sampling method and phase shift frequency sampling method, the effectiveness of the method is verified and the condition of the phase-shift factor is given.

In the final step of approaching and docking proximity of space rendezvous and docking, it is necessary to measure the relative position and posture of two spacecrafts with high precision using by optical imaging sensor. The image quality of the optical system itself of optical image sensor, to a great extent, will influence the accuracy of navigation information of rendezvous and docking, and even determine the success or failure of rendezvous and docking task. The image telecentric optical system, adopted by the multi-components and retrofocus structure and designed by the hyperfocal distance theory, not only can realize clear imaging from 2 meters to infinity, but also can make sure the center position of image that is imaged by the object from 2 meters to infinity basically invariant. It used the method of "S" type correction of distortion and corrected the distortion of edged field of view (FOV) and 0.8FOV synchronously, which realized the relative distortion less than 0.028%（absolute distortion less than 0.78μm）in the range of 30° fields of view, and met the requirements of the high precision of imaging system and illuminancy uniformity of different fields of view.

Inert gas packaging and vacuum packaging are the main packaging method of photodetectors. A multi-stage thermoelectric cooler (TEC) is used to provide low temperature environment for extended wavelength InGaAs focal plane. A gas charging device is established to study nitrogen and krypton gas packaging. The performance of multi-stage TEC under different packaging atmospheres is tested, and the temperature field distribution is simulated by finite element analysis using FLoEFD software. The results show that in inflatable environment the cold side of TEC can achieve low temperature below 220K for the extended wavelength InGaAs detector. Gas conduction heat loss and gas convection heat loss are introduced into the inflatable packaging compared with vacuum packaging, and the relationship between temperature difference and input current under different packaging atmosphere is obtained. The cooling effect of TEC in krypton gas packaging is superior to that in nitrogen packaging, and the temperature of the cold platform can reach 211K and 215K respectively under the same input current of 4.5A. The results of FLOEFD finite element analysis are basically in agreement with the measured results, and the temperature uniformity of the focal plane is good. Because of without using the getter, Inert gas packaging is an economical packaging method for infrared detector.

Light guide plate (LGP) plays an irreplaceable role in backlight module of liquid crystal display (LCD) systems. Based on interactive design of Gtools and Tracepro, we propose an effective design method of scattering dots array for LCD backlight in this paper. This method first initializes the scale of the scattering dots in Gtools, then evaluates illumination distribution in Tracepro, and finally determines the array layout of the scattering dots from the interactive optimization between Gtools and Tracepro. This method can flexibly adjust the light emission in each sub-area of the LGP, which has scientific significance and practical value in some ways.

Inductively coupled plasma processing (ICPP) is regarded as an unrivaled technique in the field of aspheric and freeform optics fabrication for its non-contact chemical etching and high efficiency. In this paper, to evaluate the obliquely incident machining behavior of removal function during inductively coupled plasma, we did some plasma beam line scanning test treatments on the fused silica surface with different obliquely incident angles in two vertical directions. Test results show that the full width at half maximum (FWHM) of the footprint of removal function increases from 13.1699 mm to 14.8368 mm with the increase of the obliquely incident angle from 0° to 30° along the X-direction line scanning processing, and that of another direction only increases from from 13.1699 mm to 14.0598 mm. Furthermore, the material removal rate in both directions reduces in a small range with the increase of the obliquely incident angle less than 10° under our processing condition. Therefore, test results demonstrate that the three-axis machining system can be effective supposing that the local slopes of the part to treat are less than about 10°. The presented conclusions can provide technical guidance for fused silica aspheric and free-form optical surface machining.

In this paper, from two aspects of abrasion of grinding disk and stability of removal function, this paper compares the machining methods of planet movement and smooth running. On the basis of the Preston hypothesis, based on the kinematics theory, the grinding disk theory wear model of planet movement and smooth running is established, and the three-dimensional model of grinding disk wear under two kinds of motion is simulated by MATLAB. The correctness of the theoretical wear model and three-dimensional simulation wear distribution model of the grinding disk is verified by experiments. The experiment found that the wear of the grinding disc under smooth running tends to be uniform, and the wear of the grinding disc under the planet movement increases along the direction of the radius increasing. It is assumed that with the continuous abrasion of the grinding disk, the degree of fit between the grinding plate and the workpiece surface becomes worse, and the removal quantity of workpiece material is affected, which will affect the stability of the removal function. Through the removal function experiment of an hour, we find that the stability of the volume removal rate of the removal function fluctuates within 7% and the stability of the peak removal rate fluctuates within 6% under the smooth running, while the stability of the volume removal rate of the removal function fluctuates within 29% and the stability of the peak removal rate fluctuates within 12.3% under the planet movement. The results show that the wear of the smooth running is uniform and the removal function is stable. Therefore, the smooth running is more suitable for high-precision modification than planet movement.

The effect of ion beam etching process on the surface quality, the surface roughness and the laser-induced damage threshold at 351nm was carried out. Research results reveal that the laser-induced damage threshold of fused silica was enhanced with the increase of etching depth when the etching depth was less than 800nm, and could be further enhanced about 30% at 800nm etching depth, however the laser-induced damage threshold began to decrease with the further increase of etching depth(more than 800nm). The test results of surface microtopography, laser damage morphology, and surface roughness reveal that the ion beam etching process can remove polishing re-deposition layer without degrading the surface condition at a smaller etching depth so as to enhance the laser-induced damage threshold of fused silica, however further ion etching which can produce impurity particle often results in a decrease rather than an increase of laser-induced damage threshold.

The wave front gradient is a key parameter to the low frequency wave front of the aspherical components, which ultimately affects the focusing performance of the optical system. CCOS（Computer Controlled Optical Surfacing）is a technique widely used in precision polishing of aspherical lens. First of all, the reasons for the deterioration of the gradient are analyzed. Secondly, the control technology is designed for various main factors. This paper also found a technological scheme that could inhibit the error of the wave pattern in theory. Finally, combined with the actual conditions of engineering processing, the results of control process methods are verified. The results show that GRMS value of a large aperture（400mm × 400mm）aspheric element is reduced from 0.013 λ/cm to 0.008λ/cm.

Computer Controlled Optical Surfacing (CCOS) technology is one of the most commonly method in optical manufacture. Though CCOS is efficient, there is an unavoidable disadvantage. Middle and high spatial frequency errors, also called the ripple errors, will be left over on the optical surface. This kind of error may have a serious impact on the performance of the optical system. Focus on the grating path, the quantitative relationship between step size and ripple errors is obtained. In order to effectively restrain the ripple errors, a locally random path with Gaussian distribution is proposed. The surface figures that achieved by two different tool paths have been simulated. The results prove that the locally random path can re-distribute the remove amount of the surface. Therefore, the regular remove distribution caused by grating path disappears. It means that the specific surface errors can be restrained effectively.

Magnetorheological finishing (MRF) is a deterministic optical element polishing method that achieves material removal by means of the sheared and rheo-logical behavior of magnetorheological fluids. For the magnetorheological processing optics, an experimental study of the magnetorheological processing force was carried out. It was obtained that the relationship between the process parameters and element forces in magnetorheological polishing .The process parameters in MRF are the rotation speed of the polishing wheel, the magnetic field strength, the liquid flow rate, and the immersion depth. For MRF-600 magnetorheological polishing machine with polishing wheel Φ300mm, the normal forces range from 2N to 32N.According to the fitting curve between the magnetic field and the normal forces, the force is 6 times larger than that under the zero magnetic field condition. At the same time, the polished spots were collected under different magnetic field intensity. The law of the removal rate of polishing spots was obtained.

It is a critical technology to improve the optical film uniformity during the film deposition process. The ion beam sputtering and polishing system was used to prepare the film on the surface of large-aperture optical elements. A calculation method for controlling the dwell time ratio I of the ion beam working at the center and edge of optical component was proposed. The dwell time ratio I was calculated by the film thickness data obtained from the center and edge, and the dwell time ratio I was revised step by step. Then it was input in the program as one of the sputtering process parameters. The experimental results show that, when I was revised to -26.6%, uniform film can be achieved on optical elements with a diameter of 300mm-600mm. Taking a Si film on the surface of fused silica as an example, the experiment was carried out for 6 hours. The film thickness is about 212 nm, and the film uniformity could reach up to 0.42%, which meets film thickness uniformity requirements by ion beam sputtering deposition method.

In order to reduce the optical intensity of backscattering lights of the Cassegrainian optical antenna in the optical system of the laser communication terminal and improve the optical isolation of laser communication system, this paper proposes a method for designing high isolation level Cassegrainian optical antenna by increasing the characteristic value of the optical intensity of backscattering lights E/N. The method aims to improve the optical antenna isolation through reducing the optical intensity of backscattering lights along the incident optical path based on analyzing the theoretical model of the optical intensity of backscattering lights BRDF. A Cassegrainian optical antenna for laser communication is designed in this paper, and the method is used to optimize the isolation of this optical antenna by custom operands in ZEMAX. Then using TracePro software builds the optical structure model of this optical antenna before and after optimization, simulate the optical intensity of backscattering lights of each model, calculate and analyze the isolation of each model by using simulation data respectively. It is show that the backscattering rate of the system decreases from 0.0011956 to 0.00007515, and the isolation decreases from -29.224dB to -41.24dB. Optimization has improved the isolation 12.017dB of the optical system through use the method.

Aiming at the processing of infrared optical parts and the adjustment of infrared optical system, key links, such as surface shape change, optical axis deviation, etc and influencing factors were analyzed in detail caused by internal defects and stress of Infrared optical parts, differences in material properties and adjusting tightening force from the aspects of optical processing and opto-mechanical adjustment, whose influence on the final performance and quality of the infrared system was pointed out. On this basis, the problems existing in the current manufacturing process of the infrared optical system were sorted out, and the related technology which was needed to be carried out and the content of continuous attention were put forward to realize the refinement and parameterization of infrared system process control, and improve the manufacturing performance and quality of infrared optical system.

A collimating system is designed by two orthogonal aspheric cylindrical lenses, which is used to collimate the the output beam of the Laser Diode (LD). The theory of light transmission is used to analyze the optical collimating system. The theoretical expressions are derived and the numerical results are obtained. The nonlinear Levenberg-Marquardt (LM) fitting algorithm based on the trust-region rule is applied to the surface shape evaluation. Residual analysis is used to test the rationality of the model hypothesis, and a simple analysis is made on the source of the error and the data optimization process. And the optical simulation of model optimization results is established. Simulation results show that the semidiverging angles of 20° and 9° for the fast and slow axes of semiconductor laser beam are both reduced to 0.05 mrad after passing the collimation system which is much better than that of a normal cylindrical lens collimating system 3 mrad. A uniform circular spot can be formed in the far field by adjusting the distance between the two aspheric lenses.

The Atmospheric pressure plasma jet (APPJ) is a very efficient tool that can be employed in the damage-free optical manufacturing. The deep understanding of the temperature field and flow pattern inside the discharge can be a useful tool for optimizing these devices. In this paper, simulation analysis and experiment research on the surface temperature distribution are presented. Through FLUENT finite element analysis software and the heat transfer theory in the flow field, the surface jet characteristics of components are analyzed. Combined with the temperature measurement experiments, the characteristics of surface temperature field modeling are verified, which provides an analysis basis for the comparative study of subsequent temperature and thermal deformation.

Cutting force is a key factor of the cutting plans design, cutting conditions setting, tool wear evaluation and even machined surface topography prediction. However, little research has been conducted on the analysis of cutting force in ultra-precision fly cutting (UPFC). This paper presents a theoretical and experimental study on the cutting force modelling in UPFC of groove. In the present study, an analytic cutting force model has been established to predict the cutting force amplitudes both in the feed direction and thrust direction. Experiments were conducted to verify the simulation results. Theoretical and experimental results show that cutting force in UPFC is figured as a force pulse followed by a series of free vibration signals, cutting parameters such as cutting depth, feed rate seriously affect cutting force amplitude.

Continuous polishing is a significant process to fabricate optical workpiece with nano figure precision. The figure of the optical workpiece is to a large extent dependent on the surface shape of the pitch lap. In this study, a novel method is proposed to determine the lap shape error by moving the measurement point in a generally radial direction while the lap rotates and correct the lap shape error by employing a small heat tool considering its viscoelastic property. It is validated that the surface shape error of the pitch lap can be corrected dramatically by the method, and the workpiece figure attempts to target the lap shape so as to reach a uniform material removal.

Whether to diagnose accurately the laser damage of optical film or not is the key to measure the laser-induced damage threshold of the optical film, which directly affect the accurate assessment. In this paper, based on the plasma theory, researches on the characteristics of the laser-induced plasma while the optical film has been damaged in detail have been done, and theoretical and experimental analyzing on this plasma shockwave has been taken with acoustic method. The laser damage diagnosis method of optical film based on the characteristics of plasma has been proposed. The results show that, this method, taken the atomic spectrum of the laser-induced plasma spectrum and the peak value of pressure of the laser-induced plasma shockwave as the criteria, can efficiently improve the test accuracy of the laser-induced damage threshold of optical film.

With high resolution, low cost and short manufacturing cycle, the optical load of aluminum–based has attracted more and more attention from researchers. In this paper, the optical system is briefly introduced and the tolerance analysis is carried out. Secondly, the whole structure of aluminum space camera is designed. The main mirror adopts integrated design method to reduce two-stage assembly. In order to ensure the assembly is simple and reliable, the whole machine adopts cylinder support. Then, the structure of the integrated main mirror is optimized, the lightweight rate reaches 30%, and the machine's quality is 1.8kg. Finally, the mechanical characteristics and temperature adaptability of the whole machine are analyzed by means of finite element analysis. The analysis results show that the system's MTF value is more than 0.2 at 20±5°C temperature and static environment, which meets the imaging requirements; and each mode is larger than 100Hz, satisfying the dynamic requirements.

Optical windows are important for a wind tunnel to enable observation or imaging of the internal flow-field. In order to reduce the interference to the internal flow and not to modulate the input observation ray field as much as possible, the interior and exterior surfaces of the optical window often adopt complex free-form surface design and must be used in pairs. This requires high accuracy of both the surface form and their relative position. In this paper, Trace-Pro optical software is used for the ray tracing analysis of the wind tunnel observation window defined by discrete points on the inner and outer surfaces. The conclusion is that the collimated beam is also the collimated beam after passing through the single observation window, which means the transmitted wave-front can be well resolved by a standard interferometer. The ray data in Trace-Pro is imported into MATLAB to obtain the modulated wave-front error which is contributed by the difference between the inner and outer surfaces of the monolithic optical window. It hence can be used to guide the corrective machining of the window surface. In addition, the influence of different misalignment on the interferometric test of the window is analyzed. Finally, the method is experimentally demonstrated on an optical free-form window. The surface positioning error is reduced with corrective machining based on the measured transmitted wave-front.

According to the characteristics of the reflective optical microscope lighting system, an improved Köhler illumination system for the full-field optical coherence tomography system (FFOCT) was designed to realize the illumination of biological samples and living biological tissues. The illumination system differs from the conventional Köhler illumination system. The filament of the halogen lamp is imaged on the back focal plane of the microscope objective, then parallel light is incident on the sample plane. The improved Köhler illumination system uses a halogen lamp as the light source and is divided into two parts: the condenser front and rear groups. The front condenser group uses two double-glued structures, and the rear group uses a double-coupled lens. The optical design software Zemax was used to optimize the design, and the illumination analysis software Tracepro was used to trace the ray and simulate the imaging of the light source in the front focal plane of the microscope objective. The entire improved Köhler illumination optical path has a total length of 594 mm, the diaphragm is 122 mm from the front group of the condenser, 99 mm from the rear group, and the working distance is 292 mm; the luminous efficiency of the receiving surface is as high as 60.38%, and the edge of the light spot is smooth and clear. The illumination system makes full use of the optical power emitted by the light source and facilitates the placement of a device such as a splitting prism between the condenser and the microscope objective, which satisfies the requirement of the entire machine well.

For the rapid development need of the digital light processing (DLP), we designed a mini-projection lens applied to 0.65” DLP with ZEMAX. The mini-projection lens is composed of 9 group of 10 lenses, total length is 90mm, and the maximum aperture is 36mm. It has simple structure, small size, low processing and assembly costs, suitable for mass production. F-number is 2.4, projection ratio is 1.56, effective focal length is 22.67mm, and back working distance is 28mm. Its modulated transfer function (MTF) in all fields is higher than 0.75 at 66lp/mm, and higher than 0.6 at 100lp/mm, which has good image quality. The full field distortion is less than 0.2%, meeting the low distortion requirement of the projection lens.

Different from the abrasive grinding process, diamond particles are solidified in matrix materials and the fixed motion between abrasives and workpieces which good for precision machining, so we take this method to grind glass-ceramic reflector and a good surface quality was obtained by using diamond W14 pellets. Through the grinding process experiment, the material removal rate on the glass-ceramic reflector are measured at the given rotation speed, the pendulum frequency and pressure by W28, W14, W5 pellets. In addition, the surface roughness measurement results show that the surface roughness of 181.6nm can be obtained by using W28 diamond pellets. The experiment also demonstrates that the surface roughness of the glass-ceramic reflector is decrease with changing pellets in a smaller diamond size. After ultra fine grinding processing by using W5 diamond pellets, finally, the optical surface with a roughness of 20.8nm is obtained. The experimental results show that the method of using diamond pellets to process glass-ceramic reflector can replace the traditional abrasive finishing process in rough grinding, fine grinding and superfine grinding.

In recent years, monolithic multi-surface image systems are widely concerned with the deeply development of optoelectronic imaging system and the ultra precision machining technology, most of these systems consist of multiple mirrors, and these mirrors are machined on one substrate or grouping processing on two substrates. In this paper, we discuss the optical design of visible imaging system with a filed of view 2° based on common-axial folded optical system. This study described the optical design of visible all-reflective imaging systems based on the aviation aluminum material. It works in the 0.45~0.75μm wavelength bands. The visible imaging system includes two elements, the first one is a flat mirror, and the second one is an optical element with four concentric zone aspherical mirrors, each concentric zone aspherical surfaces are 12-th order, the beam is folded and reflected between concentric zone aspherical mirrors and flat mirror, and then focused on the image plane. The surface accuracy of submicron order and position accuracy of micron order, and the technology of single point diamond turning are used to ensure the coaxality accuracy of the concentric zone aspherical mirrors. According to the optical design results, the quality of imaging arrives at the diffraction-limitation. On this basis, we design the focusing mechanism and complete system manufacturing; assembly and imaging experiment. The final system has the advantages of compactness, convenient thermal management and simple installation. It can potentially be applied to the optical system of the unmanned aerial vehicle system.

The design and manufacture of Continuous Phase Plates (CPPs) with a large aperture is very significant and useful for kilojoule and megajoule-class laser systems, such as the Inertial Confinement Fusion(ICF) due to it has the advantages of precise control of beam-shape and high energy availability ratio. In order to improve the quality of the focused beam in the Inertial Confinement Fusion (ICF) system and reduce the processing difficulty of components, a theoretical design model of the continuous phase plate based on the Magnetorheological Finishing (MRF) technology was established, and improved the traditional Gerchberg-Saxton (GS) algorithm from the aspects of initial phase selection, phase unwrapping, filtering, and speckle spectrum control. The results show that: Compared with the conventionally designed continuous phase plate (CPP), the improved GS algorithm can control the size of the CPP processing unit, meet the requirements of magnetorheological processing technology, better control the focal spot profile, and reduce the modulation of specific frequency bands.

Aiming at the problem that the surface defects of the substrate, which are caused by the large size and uneven distribution of the polishing powder, the screening and classification of cerium oxide polishing powder was studied. The screening method of water dispersion was adopted. The impacts of the dispersion method, dispersion parameters, screening number, the concentration of polishing powder and settling time on the size and uniformity of the polishing powder were studied. The appropriate technological process and process parameters were determined by experimental study. The control over the granularity and uniformity of polishing powder was realized. Morphology of the polishing powders was studied by using SEM and granularity of powders was measured by laser granularity analyzer. The particle size of the polishing powder after screening is D (0.5) =1.6μm~1.8μm. The width of the particle size distribution is not over 3.3μm (D (0.9) ~D (0.1)). By the tests of white light interferometer, Ra of the ultra-smooth surface polished with the filtered cerium oxide is no higher than 0.3nm.

With the aim to conveniently evaluate the abrasive worn states in precision grinding, this paper presents an image detection and evaluation function for grinding wheel’s micro-surface recovering. Any curved object have different focus level in the same image. With a fixed focus detector drived by motor, the information of abrasive height can be extracted from image sequence by focus evaluation. We propose and compared two method and find Gray-Level-Variance (GLV) have a better robustness on wheel’s surface recovering. The arithmetic works better and smoother when LULU operator is cooperated. Finally, we make a comparision between the result of GLV and ultra-depth 3D microscope in comparative section. The information of single abrasive and diamond pellets are concerned to prove the arithmetic’s validity and stability.

Hafnium oxide (HfO₂) thin films has been prepared on glass substrates at room temperature by thermal evaporation technique using HfO₂ powders (99% purity) and then are annealed at different temperatures ranging from 150° to 450° for 24 hours in air. The effects of the annealing temperatures on the structural and optical properties of the HfO₂ thin films were studied. Amorphous structures of the HfO₂ films were researched by XRD technology. The results of the study show that the state of the HfO₂ film changes from amorphous to polycrystalline with the increase of heat treatment temperature and the the stress is released. Besides, the refractive index of the films decreases and the band energy changes significantly. Therefore, the heat treatment can effectively change the film properties and it is necessary to comprehensively select the optimal heat treatment temperature according to the specific application of the HfO₂ thin films.

Traverse oscillating cutting is one of the cutoff process with low cutting forces, low contact zone, favorable cooling, long cutting time which is suitable for hard and brittle materials. The cutting process will generate residual stress, which affects the surface profile and mechanical properties. In this paper, the fused silica glass is selected to carry out the cutting experiment. The effect of the two cutting modes, horizontal cutting and longitudinal cutting on the residual stress was studied experimentally. And the parameters such as rotating speed, feed speed and cutting depth were optimized. The results show that both cutting modes produce large residual stress at the edge, while the horizontal cutting in the middle region produces smaller residual stress. There is no significant linear relationship between the parameters and residual stress, which has an optimal range. And an optimal traverse oscillating cutting technique is obtained.

HF-based etching has been an effective method to increase the laser induced damage thresholds (LIDTS) of fused silica optics. In this research, the effect of etching parameters on the surface quality and laser damage performance of fused silica with Megasonic-assisted HF acid etching has been investigated systematically. The fused silica samples (50mm in diameter and 5mm thick) were maufactured through the conventional grinding and chemical mechanical polishing process, these processed samples are etched with different etching parameters. Our results show that the frequency and distribution of megasonic field will bring great effect on the surface quality of optics. The LIDTS were measured by 1- on-1 mode, results showed that the 1.3MHz megasonic field and a certain amount of etching depth will benefit the laser damage performance of fused silica optics.

For the high demand of large aperture optical element, the regular trajectory errors in machining marks of double-side polishing need to be determinately controlled. The mechanism and control method of the regular trajectory errors in machining marks were deeply studied. The process was simulated and compared with the experiment. The method of active translation and pendulum motion and polishing plate correction were proposed, proved to be efficacious on eliminating the regular machining marks by the groove of the polishing pad and local surface figure errors of the polishing plate. The method of dynamic loading and motion combination was adopted, retaining the independence of the original fast convergence process on surface figure. For the optical element with 430mm×430mm×10mm, the surface figure was controlled below 1λ(PV, λ=632.8nm). Meanwhile, the regular machining marks repeatedly produced were eliminated, which provided the essential condition for the intermediate frequency index in the rear stage, small tool precision polishing, and the high efficiency and stable machining of the optical element in the index system was realized.

Subsurface damage (SSD) caused during machining process can decrease the mechanical strength of BK7 glass optical elements, which would shorten the lifetime. Rotary ultrasonic face milling (RUFM) is interest of many engineering applications, especially for machining optical glass which need the high surface quality and less SSD depth. In this paper, the effects of several critical factors (i.e. spindle speed, feed rate, and cutting depth) on machining quality and efficiency in RUFM were investigated experimentally and further analyzed. The relationships between the process parameters and the machining quality were obtained. Moreover, an optimized method was proposed for the further applications of RUFM, taking care of both machining quality and efficiency.

The phonological network multi-spectral camera has a complicated internal structure. The camera is a composed of eight lenses, and the light path is divided into eight channels. There is a lot of stray light.So deep stray light analysis and suppression design must be performed to reduce the influence of stray light. This paper analyzes the characteristics of phenological network multi-spectral camera system. Two different baffles are designed, and a regional calculation method is proposed to detect the shading performance of the baffle.Then, the stray light analysis was performed on each channel of the phenological network multispectral camera with TracePro. According to the analysis results, PST curves under different conditions are compared, and the appropriate baffle is selected. Finally, shading performance of the baffle was verified through experiments.

To solve the problems existing in the Modulating retro-reflector optical system which can not simultaneously satisfy the wide field of view, reversibility of light path, small F number and all lens are spherical surface, an optical system with wide field of view and near the diffraction limit is designed. The structure of optical system is optimized and analyzed with an optical design software, 30 degree view field angle and F number of 1.3 CMERR optical system has been designed, all lens are spherical lens and near diffraction limit. The results show that within the whole field of view, the lens retro-reflects incidence beam perfectly, and can match the small size modulator. It ensures the contrast ration of the whole system which has advantages of low cost and easy processing.

In order to process full spatial frequency range error of steep aspheric surface, a self-adaption polishing tool was designed based on silly putty, and the principle of silly putty used on polishing tool to process middle and low spatial frequency errors was analyzed. The effect of silly putty’s viscosity on pressure was calculated by Newton’s law of viscosity. Stability of polishing pressure was compared between self-adaption polishing tool and pith lap through calculating polishing pressure. A 470mm aperture concave aspheric whit F#1.8 and 1.8mm departure from the best-fit radius is employed to operate experiment. It was verified that self-adaption polishing tool have the capability processing full frequency range error.

Compared with conventional grinding tools, the chemical vapor deposition (CVD) diamond grinding tools have lots of advantages. However, the practical application of CVD grinding tools is limited, because of the small chip-holding space of abrasive layer. Based on the previous research, the structured grinding tools identified as an available method to improve grinding performance. Therefore, the micro-structured CVD diamond tools were invented. In this paper, the picosecond pulse laser was adopted to machine the micro-structures on CVD diamond. The ablation threshold of CVD diamond film was obtained with picosecond pulse laser. And then, the micro-grooves were machined on diamond film surface with different laser machining parameters. The effects of defocus, laser power, scanning speed, scanning times and machining offset on groove width and depth were analyzed respectively.

With the development of precision glass molding (PGM), low Tg glass molded lens are more and more used in optical system, recently, especially in the fields of safe security and car assist system, which have large market demand. Coating technology for mold is one key of support technology for precision glass molding, and the researches on the coating for precision low Tg glass molding is urgently needed. In this paper, aiming at the coating technical demand of low Tg glass molding, the coating duration and damage principal are discussed after fast coating facility testing. Three kinds of coating system (W_xC_y-PtIr-D_ZK3,W_xC_y-CrAlN-D_ZK3, W_xC_y-TiAlN-D_ZK3)for molding are analyzed with SEM. The results show the PtIr alloy coating is suit for low Tg glass precision molding.

Various communication satellites are more and more important for the country’s strategic development. As the eyes of satellites, Antennas play a key role in the entire satellite system and directly affect the communication quality of satellite systems. The surface accuracy of antenna restricts satellite communication to some extent. In the deterministic modification and accuracy improvement during antenna surface processing, it is necessary to reduce the deformation caused by the gravity. General method is to fix a feedback force array behind the antenna, which could offset the gravity deformation of the satellite surface. Voice coil motor is a special type of direct drive motor, which has the characteristics of generating magnetic force in the magnetic field and the current applied on the coil is proportional to the characteristics to achieve deterministic force or linear displacement set. Voice coil motor has a simple structure, small size and fast response, which is suitable for accurate displacement and force control. In this project, voice coil motor is used to realize the gravity-unload of the deformation in the CFRP antenna surface processing, and a model is established according to the shape characteristics of the CFRP antenna to be processed. At the same time, a distributed control system (DCS) based on CAN Modbus is designed to implement accurate control of the force array. Through a host-PC, deterministic forces could be easily transferred to each control unit. This paper shows out the design of single unit of force control based on voice coil motor, meanwhile, the DCS system and software on host-PC are illustrated at last.

The ultra-precision single point diamond flycutting is an effective way for finishing potassium dihydrogen phosphate (KDP) crystals. However, the dynamic performance and motion precision of the machine tool would introduce the errors and have an adverse effect on the surface quality of elements. In this study, a significant method is presented to trace error sources by combining monitoring the rotary errors and analyzing the machined surface. On the one hand, forward recursion method is adopted. Based on the online measuring platform, the radial error, axial error and inclination error of spindle rotation can be obtained. Through the Fourier transform algorithm, the frequency information in each direction is known. Furthermore, the waviness along the feed direction is identified, which is determined by the rotation fluctuation. On the other hand, a novel method for errors tracing is presented by a reverse thinking mode based on the surface topography. The wavelet analysis is carried out along the cutting direction, and the obvious waviness appears in the 4th layer, of which the dominant frequency is 594Hz. Through the knocking test for the spindle system, the waviness error along the cutting direction is determined as the modal vibration of the spindle system.