An experimental outdoor optical wireless data communication system with a differential decision threshold (DDT) using filtering techniques in the presence of sunlight or artificial light is presented. In the proposed system, an optical filter is employed for reducing ambient light noise and sunlight, and a red color filter is also applied for detecting a specific wavelength only at the receiver with DDT. Unlike previously reported methods, such as spread spectrum techniques, combining methods, and preamble methods, the proposed method is very practical and efficient in that it uses filters on the top of the photodiode to occlude obliquely incident unwanted light under the realistic assumption that the light noise does not come directly into the photodiode. The proposed outdoor visible light communication can thus facilitate a practical free space outdoor optical wireless data transmission system.

Saliency extraction has become a popular topic in imaging science. One of the challenges in image saliency extraction is to detect the saliency content efficiently with a full-resolution saliency map. Traditional methods only involve computer calculation and thus result in limitations in computational speed. An optical imaging system-based visual saliency extraction method is developed to solve this problem. The optical system is built by effectively implementing an optical Fourier process with a Fourier lens to form two frequency planes for further operation. The proposed method combines optical components and computer calculations and mainly relies on frequency selection with precise pinholes on the frequency planes to efficiently produce a saliency map. Comparison shows that the method is suitable for extracting salient information and operates in real time to generate a full-resolution saliency map with good boundaries.

Infrared texture is an important feature in identifying scenery. To simulate infrared image texture effectively at different distances, we propose a model of infrared image texture generation based on scenery space frequency and the image pyramid degradation principle. First, we build a spatial frequency filter model based on imaging distance, taking into account the detector’s maximum spatial frequency, and use the filter to process a “zero” distance infrared image texture. Second, taking into consideration the actual temperature difference of the scenery’s details due to variation of the imaging distance and the effect of atmospheric transmission, we compare the actual temperature difference with the minimum resolvable temperature difference of the thermal imaging system at a specific frequency and produce a new image texture. The results show that the simulated multiresolution infrared image textures produced by the proposed model are very similar (lowest mean square error=0.51 and highest peak signal-to-noise ratio=117.59) to the images captured by the thermal imager. Therefore, the proposed model can effectively simulate infrared image textures at different distances.

Of all the animal species in the world, insect species are by far the most numerous. Insect-image recognition systems are conventionally based on color or shape features. However, for species in which the color and shape features are very similar, it is necessary to use additional texture information to ensure a reliable recognition result. In most image-based recognition systems, the texture information is obtained by means of discrete wavelet transformation (DWT). However, the DWT performance is readily affected by noise. Accordingly, the present study proposes an insect image recognition system based on a k-nearest neighbor (k-NN) clustering algorithm, in which the Sobel operator is used to extract the gradient intensity features of the image of interest, and the similarity of the image to known images is calculated using an unmatched-point Hausdorff distance method. The experimental results show that the proposed system has both a short recognition time and a high recognition rate.

We present a cube data correlation-based correlation mapping optical coherence tomography (cube-cmOCT) method to reconstruct small blood vessel maps. In the cube-cmOCT method, the two adjacent cube data are correlated to extract blood flow information. Both phantom experiments and invivo experiments were performed to demonstrate the advantage of the proposed method in improving the SNR of blood vessel maps without increasing the window size in the xz plane and offering a clear image of the small blood vessels almost missed by the conventional cmOCT method.

We propose an effective image denoising filter that combines an improved spin filter (ISF) and wave atoms thresholding (WA) to remove the noise of fringe patterns in electronic speckle shearing pattern interferometry. The WA is first employed to denoise the fringe to save the processing time, and then the ISF is further used to remove noise of the denoised image using WA to obtain a better denoising performance. The performance of our proposed approach is evaluated by using both numerically simulated and experimental fringes. At the same time, three figures of merit for denoised fringes are also calculated to quantify the performance of the combined denoising filter. The denoised results produced by ISF, WA, and bilateral filtering are compared. The comparisons show that our proposed method can effectively remove noise and an improvement of 12 s in processing time and 0.3 in speckle index value is obtained with respect to ISF.

Measuring surfaces with high reflectivity variation via structured light illumination requires accurately identifying saturated pixels in captured images. However, conventional methods simply determine saturation by intensities, which is susceptible to a camera blurring effect and random noise. To solve this problem, we present a method that uses the magnitude of a nonprincipal frequency component to identify saturated pixels. Experimental results demonstrate that 1) higher accuracy of three-dimensional reconstruction can be achieved and 2) high-contrast surfaces can be accurately reconstructed.

In order to expand the field of view in spatial light modulator-based phase contrast microscopy, we employ a two-image recording method with digital postprocessing. Using this approach, we suppress the superimposed unwanted diffraction orders on the image sensor, thus eliminating the necessity to assure a strict separation of the diffraction orders. These methods allow for a significantly smaller microscope setup and an increased effective spatial bandwidth product. We apply this method for a number of phase contrast methods to show its capabilities and limitations. Mainly, the signal-to-noise ratio is decreased by η/2. Furthermore, we employ a simple field-dependent aberration correction scheme to improve the image quality.√In order to expand the field of view in spatial light modulator-based phase contrast microscopy, we employ a two-image recording method with digital postprocessing. Using this approach, we suppress the superimposed unwanted diffraction orders on the image sensor, thus eliminating the necessity to assure a strict separation of the diffraction orders. These methods allow for a significantly smaller microscope setup and an increased effective spatial bandwidth product. We apply this method for a number of phase contrast methods to show its capabilities and limitations. Mainly, the signal-to-noise ratio is decreased by η/√2. Furthermore, we employ a simple field-dependent aberration correction scheme to improve the image quality.

We present an intracoding method that is applicable to depth map coding in multiview plus depth systems. Our approach combines skip prediction and plane segmentation-based prediction. The proposed depth intraskip prediction uses the estimated direction at both the encoder and decoder, and does not need to encode residual data. Our plane segmentation-based intraprediction divides the current block into biregions, and applies a different prediction scheme for each segmented region. This method avoids incorrect estimations across different regions, resulting in higher prediction accuracy. Simulation results demonstrate that the proposed scheme is superior to H.264/advanced video coding intraprediction and has the ability to improve the subjective rendering quality.

The accurate and dense real-time acquisition of three-dimensional (3-D) data using a low-cost structured light system remains an ongoing topic in the computer vision community, as it is difficult to achieve all these features simultaneously. Among several techniques, the pseudorandom array technique is widely used in real-time 3-D scene capturing, as it tends to concentrate the entire coding scheme into a single pattern. However, existing pseudorandom array decoding methods cannot decode a given symbol in real time when missing neighbors exist. As a solution, we propose a dual pseudorandom array encoding and decoding method and a hole-filling method, which can improve the reconstruction accuracy and time. We experimentally compared our method with several others to verify that our method captures 3-D scenes quickly and densely.

Optical target tracking by regular target bearing measurements and target range in a lower and scheduled measurement rate is considered. Variance of the target range estimation error is used as the scheduling criterion. For this purpose, target dynamic state vector in modified spherical coordinates is stated in such a way that all target states are decoupled from the range-related target state. Target state dynamic equations in modified spherical coordinates for nearly constant velocity, nearly constant acceleration, and coordinated turn rate kinematic models are analytically derived. For resulted state dynamic equations, an unscented Kalman filter interactive multiple model with range measurement scheduling is utilized as a tracking filter. It is shown that target states are estimated properly and the applied filter has high performance in maneuvering target tracking.

In recent years, inverse moiré methods have been developed to reconstruct micro/nano-scale planar periodic structures with a larger field of view than those constructed using conventional methods. In these methods, moiré fringes generated by superposition of the periodic structure and a reference grating are analyzed to reconstruct the periodic structure. There are two approaches to inverse moiré methods: the fringe-centerlines method and the phase-shifting method. The former has lower accuracy and is difficult to automate, while the latter requires at least three moiré images with complicated processing. A reconstruction method for planar periodic structures using Fourier analysis is proposed. This method can be used to characterize the micro/nano periodic structure from a single microscope moiré pattern. At the same time, when combined with a linewidth characterization method, the period and linewidth of the microstructure can be obtained simultaneously. As practical examples, the period and linewidth of a scanning electron microscopy raster are calibrated. Then the microstructures of a micro-electroformed grating and a butterfly wing are reconstructed using the calibrated system. The proposed method provides a tool for the characterization of large area micro/nano periodic structures. Further, this is a promising approach to detect defects in periodic structures.

We analyzed the effects of the focal point aberrational offset in optical transport systems for high-power lasers. Transverse and near-axial laser intensity distribution transformations in the presence of both positive and negative spherical aberrations were numerically calculated and experimentally demonstrated for different strengths. We show that spherical aberration yields considerable asymmetry of the focused beam’s caustic. Several optical transport systems with identical optical parameters (excluding the noncorrected axial beam spherical aberration) were designed. We examined the effects of the laser intensity profiles produced by these systems on the quality of oxygen-assisted laser cutting of medium-section mild steel. We show that high-quality cuts can be obtained for different shapes of laser intensity distribution. However, the greater the refocusing magnitude introduced by the spherical aberration correction, the more precisely the focal point position must be maintained during the laser cutting process.

A method to obtain a digital holographic movie by means of a point diffraction interferometer is described. By using a parallel aligned liquid crystal wave plate of size 3×3  cm², a phase shifting interferometric technique is implemented. The optical setup is able to operate at 10  frames/s. Each frame can be digitally refocused to reconstruct different planes of the three-dimensional (3-D) object. By changing the frame, the object can be refocused in a different time. As an example, we show a movie which contains two objects that are separated by 160 mm. The movie shows how, for a given time (a fixed hologram frame), we can focus at different planes (separated 0.1 mm) of the 3-D object, and by changing the frame the movement of the object can be observed.

When the optical path difference between the two arms of an interferometer is so small that only one peak exists within the measurable interference spectrum, traditional white light interference demodulation techniques based on two adjacent interference peaks are not a suitable choice. We report an experimental approach to measure the peak wavelength shifts with only a single interference peak in a fiber white light interferometer. The temperature measurement experiments prove a linear relationship between the peak wavelength and the temperature. The temperature resolution is 0.1°C in theory.

Aerosol plays an important role in regularization of the earth’s energy balance. Compared with light detection and ranging (LIDAR) pointing vertically, scanning LIDAR is a useful tool for detection of the spatial and temporal distribution of aerosols. A scanning LIDAR is constructed in which a compact 532-nm laser is bound to the telescope. Under the command from the serial port, the LIDAR can observe in different scanning modes. We introduce the structure and key parameters of the scanning LIDAR, and then verify its measurement ability by comparison with the Rayleigh–Raman–Mie LIDAR. Observation of a plume emission from a chemical factory is conducted in the northern suburbs of Nanjing, China. In order to obtain the distribution of the plume emission, the slope method and Fernald method are combined to invert the extinction coefficient of the plume. Analysis of the data shows that the scanning LIDAR can be used to monitor the relative emission concentrations of pollutants and depict the process of the pollutants’ diffusion. The scanning LIDAR can also be used to measure the three-dimensional variation of the extinction coefficient by automatic volume scanning.

Passive ring cavities are now treated as the most promising sensitive elements for cheap and technologically simple micro-optical gyros for mass production. Usually the single-mode planar waveguides are considered to be the only possible technology for such devices’ implementation. However, our analysis shows that in some cases the confocal ring cavity, characterized by the degeneration of transverse modes, can be the better alternative for such a device technology. We consider possible advantages and disadvantages of such an approach, its limitations, and technology prospects.

Light-emitting diodes (LEDs) are expected to replace existing lighting technologies in the near future because of the potential dual function of LED light (i.e., wireless communication and lighting) in the context of visible light communication (VLC). We propose a highly precise indoor positioning algorithm using lighting LEDs, an image sensor, and VLC. In the proposed algorithm, three LEDs transmit their three-dimensional coordinate information, which is received and demodulated by a single image sensor at an unknown position. The unknown position is then calculated from the geometrical relations of the LED images created on the image sensor plane. We describe the algorithm in detail. A simulation of the proposed algorithm is presented in this paper. We also compare the performance of this algorithm with that of our previously proposed algorithm. The comparison indicates significant improvement in positioning accuracy because of the simple algorithmic structure and low computational complexity. This technique does not require any angular measurement, which is needed in the contemporary positioning algorithms using LEDs and image sensor. The simulation results show that the proposed system can estimate the unknown position to an accuracy of 0.001 m inside the approximate positioning area when the pixel value is <3000.

With the constant shrinking of printable critical dimensions in photolithography, off-axis illumination (OAI) becomes one of the effective resolution-enhancement methods facing these challenges. This, in turn, is driving much more strict requirements, such as higher diffractive efficiency of the diffractive optical elements (DOEs) used in the OAI system. Since the design algorithms to optimize DOEs’ phase profile are improved, the fabrication process becomes the main limiting factor leading to energy loss. Tolerance analysis is the general method to evaluate the fabrication accuracy requirement, which is especially useful for highly specialized deep UV applications with small structures and tight tolerances. A subpixel DOE simulation model is applied for tolerance analysis of DOEs by converting the abstractive fabrication structure errors into quantifiable subpixel phase matrices. Adopting the proposed model, four kinds of fabrication errors including misetch, misalignment, feature size error, and feature rounding error are able to be investigated. In the simulation experiments, systematic fabrication error studies of five typical DOEs used in 90-nm scanning photolithography illumination system are carried out. These results are valuable in the range of high precision DOE design algorithm and fabrication process optimization.

Maskless phase-change lithographic technology is developed as a photoresist of phase-change materials. The controllable growth behavior of the crystallization region on an amorphous thin film of Ge₂Sb₂Te₅ (GST) irradiated by a laser beam is investigated; the GST thin film is deposited on a silicon substrate by the sputtering method. The results of a series of the experiments and the simulations all show that the width of a crystalline pattern is not only closely related to laser power and pulse duration, but also is apparently affected by the interactive area between the focused laser spot and thin film. The width maintains a nonlinear growth with the enhancement of the laser power until the thin film approaches melting, whereas it gradually reaches a constant value due to the local thermal equilibrium. This equilibrium makes the width irrelevant to the moving velocity with certain constraints when the laser works in continuous-wave mode. Within a defocus range of 15  μm, the widths of the crystalline patterns are obtained in a broad range from 690 nm to 8.13  μm under a 0.4-NA objective lens. By adjusting the defocus amount, some crystalline square patterns with expected widths in a wide range are fabricated, and the mean percentage error between the expected and fabricated widths is only 1.495%.

A new ultra-wide-angle projection function called fovea-stereographic is described and characterized by the relative relationship between the radial distortion level and the object field-of-view (FOV) angle, creating a high-resolution wide foveal image and adequate peripheral information to be processed within a limited computational time. The paper also provides the design results of an innovative fast fovea-stereographic fisheye lens system with a 170 deg of FOV that shows a more than 58.8% (100 deg) high-resolution central foveal image and at least 15% more peripheral information than any other light projection. Our lens distortion curve, in addition to its modulation transfer function, produces a high-resolution projection for real-time tracking and image transmission applications.

Over the last two decades, extensive research has been done to improve light-emitting diodes (LEDs) designs. Increasingly complex designs have necessitated the use of computational simulations which have provided numerous insights for improving LED performance. Depending upon the focus of the design and the scale of the problem, simulations are carried out using rigorous electromagnetic (EM) wave optics-based techniques, such as finite-difference time-domain and rigorous coupled wave analysis, or through ray optics-based techniques such as Monte Carlo ray-tracing (RT). The former are typically used for modeling nanostructures on the LED die, and the latter for modeling encapsulating structures, die placement, back-reflection, and phosphor downconversion. This paper presents the use of a mixed-level simulation approach that unifies the use of EM wave-level and ray-level tools. This approach uses rigorous EM wave-based tools to characterize the nanostructured die and generates both a bidirectional scattering distribution function and a far-field angular intensity distribution. These characteristics are then incorporated into the RT simulator to obtain the overall performance. Such a mixed-level approach allows for comprehensive modeling of the optical characteristic of LEDs, including polarization effects, and can potentially lead to a more accurate performance than that from individual modeling tools alone.

The fabrication of high-quality large-area thick Al films with a thickness around 10  μm or even more is one of the most important factors to realize high-performance large-size echelle gratings. During the deposition process of large-area Al films, Al film quality generally exhibits a different behavior along the radius (R) direction, which seriously affects the performance of echelle gratings. In this study, for the first time, we investigate the radial-quality uniformity of large-area (R=400  mm) thick (<10  μm) Al films in detail. We not only analyze the radial-quality difference of Al films prepared by the traditional electron-beam evaporation process, but also significantly improve the radial-quality uniformity of large-area thick Al films by using a coevaporation process. By comparing two kinds of film coating processes, we clarify the origin of the radial-quality difference of Al films, and prepare large-area thick Al films with excellent radial-quality uniformity.

An all-normal dispersion passively mode-locked Yb-doped fiber laser with a Bi₂Te₃ absorber is presented. The modulation depth of this kind of saturable absorber was measured to be 8.4%. By incorporating a Bi₂Te₃/PVA film into a Yb-doped fiber laser oscillator, a mode-locked fiber laser oscillator was achieved. The repetition rate and the central wavelength are 25.6 MHz and 1052.7 nm, respectively. The 3-dB spectral width is 0.45 nm and the pulse duration is 417 ps. The results indicate that topological insulator Bi₂Te₃ possesses the potential for ultrafast fiber laser application.

We demonstrate a 1484-nm two-cascaded Raman mode-locked fiber laser based on the intermode-beating mode-locking (IBML) technique. Through the two-cascaded Raman shifts of P₂O₅ in a phosphosilicate fiber, the continuous-wave (CW) 1064-nm Raman pump can be transferred to the 1484-nm second-order Stokes. When the intermode-beating frequency of the 1064-nm pump source matches with the 1484-nm Raman-cavity frequency, the IBML condition is satisfied, and the harmonic mode-locking at 1484-nm occurs to stably emit nanosecond pulse trains. By properly adjusting the 1484 nm Raman-cavity length, we have further realized the tuning of the mode-locking harmonic order. The 472nd- and 757th-order harmonic mode-locking operations with repetition rates of 72.728 and 116.292 MHz have been obtained, respectively. The IBML operation is stable with a radio-frequency (RF) supermode suppression ratio of 33.9 dB and RF signal-to-noise ratio of 51.8 dB.

We report a simple and complete approach to estimate macrobending losses in index-guiding photonic crystal fibers with given optogeometrical parameters. The approach is based on a previously developed simpler formulation of their effective cladding indices valid in the entire single mode region of such fibers. To check the validity of our approach, we compare our results with those obtained by an earlier scalar effective index method which is not so easily accessible. We observe our results to match fairly well with the available results. Our approach should find wide attention by system designers for its ease of use.

Terahertz (THz) emission from laser-induced air plasma is a well known and widely used phenomenon. We report that when two laser beams from the laser creating two plasma filaments interact with each other, THz absorption is observed. We believe that a change in the refractive index of the plasma causes the THz-wave absorption. The following experimental results reveal that the THz absorption becomes more pronounced with increasing pump power and that the gas species surrounding the femtosecond laser filament can also influence the THz absorption rate.

Intensity modulation and direct detection signal are sensitive to power fading and nonlinear intersymbol interference (ISI) induced by modulator chirp, fiber dispersion, and square-law photo-detection. We propose and experimentally demonstrate a Nyquist 4-ary pulse amplitude modulation and direct detection scheme relying on pulse-shaping with an electrical filter and optical equalization with a vestigial-sideband (VSB) filter in the transmitter. The power fading could be eliminated by using the VSB filter. Compared with conventional 4-ary pulse amplitude modulation, the Nyquist signal has a stronger resistance to nonlinear ISI.

In future radio access systems, base stations will be mainly accommodated in wavelength- and time-division multiplexing passive optical network (PON) based mobile backhaul and fronthaul networks, and in such networks, failed connections in an optical network unit (ONU) wavelength channel will severely degrade mobile system performance. A cost-effective in-service ONU wavelength channel monitor is essential to ensure proper system operation without failed connections. To address this issue, we propose a reflectometry-based remote sensing method that provides ONU wavelength channel information with the optical line terminal-ONU distance. The proposed method enables real-time monitoring of ONU wavelength channels without data signal quality degradation and is also able to determine if the ONUs are connected to the PON. Experimental results show that it achieves wavelength channel distinction with a high distance resolution (∼10  m). Additionally, with the method, the distance resolution for distinguishing the ONUs after the PON splitter is determined by the received signal bandwidth or the test light modulation speed rather than by the pulse width as in conventional optical time-domain reflectometry.

The characteristics of a fiber-optic Fabry–Perot interferometric acoustic sensor are investigated. An improved phase-generator carrier-demodulation mechanism is proposed for obtaining a high harmonic suppression ratio and stability of the demodulation results. A gold-coated polyethylene terephthalate membrane is used as the sensing diaphragm. By optimizing the parameters and the demodulation algorithm, the signal-to-noise ratio (SNR) and distortion ratio of 50.3 dB and the total harmonic distortion of 0.1% at 114 dB sound pressure level (SPL) (@ 1 kHz) are achieved, respectively. The sensor shows good temperature stability; the variation of the response is within 0.6 dB as the temperature changes from −10°C to 50°C. A sensitivity of 40  mV/Pa at 1 kHz and a frequency response range of 100 Hz to 12.5 kHz are reached, respectively. The SNR of the system is 60 dB (Re. 94 dB SPL). The sensor may be applied to photoacoustic spectrometers as a high-performance acoustic sensor.

By experiment we demonstrate an all-optical encryption/decryption scheme for nonreturn-to-zero differential phase-shift keying (NRZ-DPSK) signals at 10  Gbit/s using all-optical exclusive-OR (XOR) logic. The key bit stream is performed by a pseudorandom bit stream. The all-optical XOR logic is achieved by nondegenerate four-wave mixing (FWM) in a semiconductor optical amplifier (SOA), which allows high data rate operation and asymmetric optical powers of the two input bit streams. The gain dynamics and pattern effect associated with the SOA carrier lifetime are alleviated due to the constant envelope of the NRZ-DPSK signals.

A one-dimensional Fourier transform of a Rayleigh backscattering traces matrix along the traces direction method has been proposed to simultaneously extract location and frequency information of vibration in the distributed vibration sensing system based on phase-sensitive optical time domain reflectometry. Meanwhile, the signal-to-noise ratio (SNR) of the proposed method also can be improved as the signals are processed in the frequency domain since in the frequency domain, noise is “slow change” compared with the vibration. Then, experiments on two-point vibrations have been done. An SNR of 9.5 dB was achieved, and the spatial resolution is also improved to 3.7 m with a 50 ns pulse width and 2.7 km long fiber owing to the improved SNR.

This paper describes the refractometric detection of liquids based on silica multimode optical fibers which were tapered to increase the evanescent-wave overlap for higher sensor sensitivity. By precisely monitoring the production process, consistent sample parameters were achieved. More than 200 tapers with a taper waist diameter range from 6.0 to 76.3  μm were prepared from polymer-clad silica and gradient-index multimode fibers. U-shaped fiber taper sensitivities were analytically compared with straight tapers with resulting intensity sensitivities of over 200%/RIU. Crucial parameters for real sensor applications, such as measurement repeatability, reproducibility, and long-term stability, were further studied for polymer-clad silica straight tapers. Long-term stability was monitored showing stable measurement results over a 6 months long interval. Measurement repeatability and reproducibility with standard deviations of 0.55%/RIU and 2.26%/RIU, respectively, were achieved.

We probe the dynamics of objective laser speckles as the axial distance between the object and the observation plane changes. With the purpose of measuring out-of-plane motion in real time, we apply optical spatial filtering velocimetry to the speckle dynamics. To achieve this, a rotationally symmetric spatial filter is designed. The spatial filter converts the speckle dynamics into a photocurrent with a quasi-sinusoidal response to the out-of-plane motion. Our contribution presents the technology, discusses the selectivity of the spatial filter and proposes two solutions to balance phase-stepped photocurrents. Specifically, we discuss how the selectivity of the spatial filter with regard to radial speckle motion is influenced by a concurrent in-plane speckle motion. The spatial filter is emulated with a CCD camera and is tested on speckle acquisitions obtained from a controlled setup. Experiments with the emulated filters illustrate the performance and potential applications of the technology.

A narrow-band filter with a broad tuning range is designed based on a magnetic field controlled ferrite defect in photonic crystal for a terahertz (THz) wave. The resonance defect modes of a ferrite defect in photonic crystal in the THz region are studied by using the finite difference time domain method. Detailed calculations on the shifts of the defect mode frequency and transmission properties reveal that the peak frequency of transmission spectra can continuously vary from 0.77 to 0.95 THz under the external magnetic field and the bandwidth of the filter is about 0.015 THz.

Functional demonstration of a wide band, wide angular width wire-grid polarizer has been made in the framework of a user project of the European project ACTMOST (Access To Micro-Optics Expertise, Services and Technologies). The polarization function relies on linear polarizers using the wire-grid polarizer principle by means of a metal grating of unusually large period, exhibiting a large extinction of the transmission of the TE polarization in the 850-nm wavelength range. This grating achieves a broadband and especially high angular aperture reflection with low loss and permits resorting to very low cost incoherent light sources for the transmitted TM polarization. This paper will describe the design, the modeling and optimization, as well as the complete technological process chain, that has been used, starting with the photoresist grating printing using phase-mask UV-based lithography to the uniform galvanic growth of a very shallow gold grating on transparent conductive layer deposited on a glass substrate. Transmission curves for both polarizations performed on the first demonstrators will be presented.