This PDF file contains the front matter associated with SPIE Proceedings Volume 10255 including the Title Page, Copyright information, Table of Contents, Introduction, and Conference Committee listing.

To improve the over-segmentation and over-merge phenomenon of single image segmentation algorithm,a novel approach of combing Graph-Based algorithm and T-junctions cues is proposed in this paper. First, a method by L0 gradient minimization is applied to the smoothing of the target image eliminate artifacts caused by noise and texture detail; Then, the initial over-segmentation result of the smoothing image using the graph-based algorithm; Finally, the final results via a region fusion strategy by t-junction cues. Experimental results on a variety of images verify the new approach’s efficiency in eliminating artifacts caused by noise,segmentation accuracy and time complexity has been significantly improved.

A holographic display method combing the Amplitude of real picture and the phase of hologram is proposed to improve holographic display. The hologram of the onion epidermal cells was recorded in the in-line digital holographic system. Then the phase unwrapping method was used to get the real phase of the epidermal cells of the onion. Intensity distribution of onion is recorded in CCD illuminated by LED. Based on that, Burch and Kinoform coding are utilized to make CGH (computer-generated hologram) using phase and intensity obtained before. Experiments indicate that clear reconstruction image and desirable display result are achieved with this novel method, providing a new idea for development of CGH display.

To some extent, the mapping relationship between the camera and projector images determines the precision of surface reconstruction in digital close-range photogrammetry. In this paper, a new method is presented to achieve sub-pixel-level mapping between the camera and projector images. Instead of mapping the stripe from the camera to the projector, which is pixel-precision-based, a set of pixels that share the same decoded number were picked out on the camera images and their barycenter was calculated to mapped onto the pixel on the projector images. In most cases, the calculation of the barycenter is able to achieve sub-pixel precision. Compared with existing approaches based on the direct mapping of the stripe on the camera image to the projector image, the proposed method is characterized by higher accuracy in mapping the points and thus the surface reconstruction performance. The experimental results are presented to show the effectiveness of the proposed method in the improvement of the accuracy of shape reconstruction.

Different from backlight for panel display, the backlight for integral imaging should be directional in order to improve the viewing quality. A method for eliminating the flipped image and improving the optical efficiency for integral imaging is proposed by using directional backlight with diffractive grating. The light from one elemental image reaching the neighboring elemental lens can be eliminated with directional backlight. The effect of the backlight angular divergence and pixel structure on crosstalk and the viewing angle is analyzed. Simulation and experiment show the validity of the proposed method.

Phase-shifted shearography needs to extract dynamic phase of the measured object after loading, so an algorithm for dynamic phase extraction in phase-shifted shearography is proposed to analyze the speckle patterns with random phase shifts. By using correlation method, the fringe patterns with random phase shifts are obtained from the speckle patterns with random phase shifts. Then the dynamic phase distributions are extracted from one set of random phase-shifted fringe patterns by principle component analysis. The experimental results show that the extracted phases are accurate and efficient. The proposed method is non-iterative and has no strict requirement for the spatial-carrier frequency of fringe patterns, so it is suitable for dynamic shearing speckle interferometry.

In order to improve the dynamic range and the signal-noise ratio of the image intensifier, keep the flux of the screen of image intensifier constant. In the article, introduced a design of the switching power supply and tested its performance. Firstly, used a sampling amplifier amplify the feedback current signals. The feedback signals were converted into square wave signals through a digital circuit. Then, using the MOSFET in the post stage circuit produced high voltage and high speed adjustable square pulses. The frequency of the pulse is 1 kHz, the speed of the cutting edge is 20ns and the amplitude is 200V. The photoelectron emission time of the photocathode is short when the width of the high speed pulse is narrow for strong illumination. On the contrary, the time is long when the width is wide for weak illumination. The number of photoelectron is a constant no matter what kind of the illumination. It keeps the flux reaching the phosphor screen constant.

Compressive imaging（CI）can offer a versatile improvements for imaging systems, such as smaller compressed data volume and super-resolution. Among various methods to realize Compressive imaging, pushing encoding mask has attracted the most attention with its compatibility to the space remote sensing. However, complex pre- calibrations are usually needed for calibrating the encoding mask to achieve the measurement matrix for the image reconstruction. Herein, we design a pushing compressive imaging system which fixed with the function of situ calibration of the encoding mask. The pushing compressive imaging system was constructed, and the experimental results confirmed that the system had the ability for data compression and super-resolution. And above all, the system can avoid the complex pre-calibration, which makes the on-orbit calibration feasible. In the simulations, twice, three times and four times resolutions higher than the captured image’s resolution are performed respectively, which confirm that the method can improve the target image resolution based on the relative low resolution raw captured target images. Furthermore, by pushing the mask precisely which can be considered equivalent to the real pushing imaging, we have reconstructed the true super-resolution target image accurately based on the mask calibration and 6 captured pushing imaging frames.

In the last years, several techniques have been developed for the measurement of the three velocity components in a fluid plane or volume.Digital holography particle tracing velocimetry(DHPTV)was applied to observe the chain transformation process of magnetorheological fluids (MR fluids) under an external magnetic field. With the help of correlation coefficient(CC)method[1], the focus plane of standard particle target was determined. The displacement of standard target mounted on a precise displacement measurement workbench was compared with the distance measured by difference of focal planes movement. Making use of a controlled rotating platform with constant revolving speed, the rotation speed of particles was obtained after extracting the coordinates from reconstruction images. The measured speed was compared with actual speed of particles,which can be worked out through rotation speed of platform. The transformation speed was measured when magnetic particle moved along with magnetic direction under an external magnetic field. The experiments showed that a visible part of 3D velocity field could be observed in the chain transformation process of MR fluids with DHPTV.

The information warfare needs a highly transparent environment of battlefield, it follows that true three-dimensional display technology has obvious advantages than traditional display technology in the current field of military science and technology. It also focuses on the research progress of lens array imaging technology and aims at what restrict the development of integral imaging, main including low spatial resolution, narrow depth range and small viewing angle. This paper summarizes the principle, characteristics and development history of the integral imaging. A variety of methods are compared and analyzed that how to improve the resolution, extend depth of field, increase scope and eliminate the artifact aiming at problems currently. And makes a discussion about the experimental results of the research, comparing the display performance of different methods.

A tablet computer with a depth camera and a color camera is loaded on a traditional shopping cart. The inside information of the shopping cart is obtained by two cameras. In the shopping cart monitoring field, it is very important for us to determine whether the customer with goods in or out of the shopping cart. This paper establishes a basic framework for judging empty hand, it includes the hand extraction process based on the depth information, process of skin color model building based on WPCA (Weighted Principal Component Analysis), an algorithm for judging handheld products based on motion and skin color information, statistical process.

Through this framework, the first step can ensure the integrity of the hand information, and effectively avoids the influence of sleeve and other debris, the second step can accurately extract skin color and eliminate the similar color interference, light has little effect on its results, it has the advantages of fast computation speed and high efficiency, and the third step has the advantage of greatly reducing the noise interference and improving the accuracy.

Hainan Li brocade skills has been listed as world non-material cultural heritage preservation, therefore, the research on Hainan Li brocade patterns plays an important role in Li brocade culture inheritance. The meaning of Li brocade patterns was analyzed and the shape feature extraction techniques to original Li brocade patterns were advanced in this paper, based on the contour tracking algorithm. First, edge detection was made on the design patterns, and then the morphological closing operation was used to smooth the image, and finally contour tracking was used to extract the outer contours of Li brocade patterns. The extracted contour features were processed by means of morphology, and digital characteristics of contours are obtained by invariant moments. At last, different patterns of Li brocade design are briefly analyzed according to the digital characteristics. The results showed that the pattern extraction method to Li brocade pattern shapes is feasible and effective according to above method.

TOF (time-of-flight) depth camera is a 3D imaging device that can obtain high-precision distance information. It is used to estimate 3D structure directly without the help of traditional computer-vision algorithms. However, it has some disadvantages such as generated a depth map with low resolution and it has large random noise. In order to overcome this limitation, we proposed a new method with combines the confidence map and use the interpolation operation to improve the resolution of the image. In the up-sampling process, we consider the relationship between distance information generated by TOF camera and the confidence map, through a novel method that based on the confidence value to weighted for the traditional nearest neighbor interpolation, bilinear interpolation and the bi-cubic interpolation algorithm, increase the weight of the depth information with high confidence value in every way. Then through the multi-directional changes of edge gradient, the pixel points of edge region to be optimize with the interpolation. Experimental results show that ours method can improve the resolution of the depth image and optimize the edge effect.

In this paper, we present a computational orthoscopic integral imaging reconstruction method by utilizing a flexible ray tracing algorithm to overcome the pseudoscopic problem. Compared to previous works, the proposed method can directly reconstruct orthoscopic 3D images through one step ray tracing process. Thus, a real, undistorted, orthoscopic 3D images can be reconstructed various distances without the magnification and overlap process of conventional CIIR. To show the feasibility of the proposed method, the preliminary experiments are carried out and the some experimental results are presented.

In this paper, we present a resolution enhanced 3D photon counting integral imaging system to improve the visual quality of the reconstructed 3D images. In order to solve the limitation of the visual quality cause by the photon starved condition, the statistical estimation algorithm based on the 3D imaging structure is proposed to estimate the high performance photon counting images. Additionally, synthetic aperture integral imaging is utilized for imaging and reconstruction in low light levels condition. Finally, the performance of the proposed method is verified relying on the precise experimental results.

In synthetic aperture integral imaging system, a camera array is employed to obtain multiple perspective images from a 3D scene. However, the imaging lens suffer from the limitation of depth of field which disallows a conventional integral imaging system to obtain full-focus elemental images. To solve this problem, we present a multi-focus elemental images fusion method to reconstruct resolution enhanced 3D integral images. In the proposed method, depth estimation and image registration are achieved to fuse full-focus elemental images. Then, the resolution enhanced 3D images are reconstructed by using full-focus elemental images. To verify feasibility of the proposed method, the preliminary experiments are carried out.

An ultra HD, low crosstalk, high luminance uniformity, and wide field of view auto-stereoscopic display is demonstrated with the use of novel free-form surface backlight array (FFSBA) and mix-teeth Fresnel lens (MTFL) technology, in conjunction with a hybrid spatial and temporal control scenario. The luminance uniformity is shown to be higher than 95.3% even within a wide viewing angle, and the minimum achievable crosstalk can be as small as 2.2%. The moiré pattern is avoided by an equivalent anisotropic film (EAF).

This paper presents a simple and effective method, without the need for any additional recording of the intensity maps or tremendous iterative computations, to remove the complex zeroth-order term in the complex hologram for phase retrieval in two-step quadrature phase-shifting holography by utilizing the intensity in certain area in the complex hologram. We select a particular area in the complex hologram where there is negligible diffraction from the test sample to calculate the intensity. The calculated intensity value allows us to eliminate the complex zeroth-order term from the complex hologram. Exact phase distribution can then be reconstructed by using the new complex hologram without the zeroth-order and twin image noise. Experiment results have been performed to verify the effectiveness and feasibility of our proposed method.

In this paper, we propose an optical method based on integral imaging(II) and ptychography to encrypt threedimensional( 3D) information with simple architecture. The 3D scene plaintext is encrypted by a camera array and double-random phase masks via ptychography to generate a series of diffraction intensity patterns as ciphertexts. Then, the decrypting process with ptychographic iteration and II reconstruction is employed to retrieve high-quality 3D images. Since scanning light probes and parameters of II can serve as secret keys that enlarge the key space, and elemental image array generated by the II pickup has redundancy property, the security of encryption scheme can be improved significantly. Also, the decrypted 3D images in our proposed method have high-quality. Preliminary experiments are carried out, and the results demonstrate the feasibility and robustness of our proposed method. Especially, this research is suitable for real large-size 3D scene.

For the prospects of three-dimensional reconstruction technology based on structure from motion in engineering application, a high-resolution and visible band imaging system has been designed and implemented. It consists of a 5k × 5k CMOS focal plane array detector made by the ON-SEMI company, an optical system and an electronics system designed by ourselves. The electronics system takes FPGA as the control and drive processor chip and is divided into three parts: a power management module, a detector module and an image processing module, capable of finishing image compression and transmission. A sequence of images for the target of long distance away is obtained from the imaging system and the images after cropping and segmentation, aiming at reducing calculation and excluding some points irrelevant with the target during reconstruction process, are took as input of structure from motion. Seeds from the match points expand from sparse points to dense points and the initial model of reconstruction target is achieved. The experiment results show that the imaging system meet the requirement of three-dimensional reconstruction in engineering application and a new novel imaging system design of graded resolution based on bionics is proposed.

In this paper, we propose a staggered design directional backlight system in an autostereoscopic display. Currently, one of the main deficiency of autostereoscopic display is low display uniformity in both horizon and depth direction. In order to optimized display unifomity, the system mainly employs a staggered backlight array designed by a trace-back algorithm and a light shaping diffuser. As result, the horizontal dark areas are fully compensated. Moreover, crosstalk of experimental system is as low as 0.9%.

In this article, we propose a quantitative evaluation for the display uniformity in a directional backlight system. Display uniformity is divided into two research aspects - static uniformity and motional uniformity. Factors influencing uniformity deterioration are then discussed in our evaluation. Furthermore, a visualized simulation based on ray-tracing model is proposed to analyze this display uniformity in quantitative depth. Optical distribution on the screen is obtained in this simulation to provide visualized results compared with the experimental results. Our work helps to fill the vacancy for the evaluation of display uniformity on directional backlight type 3D display.

There are many 3D data structures for computing diffraction field, the description based on 3D point-cloud is the elemental method of other descriptions, the diffraction field of 3D scene can be thought as the superposition of the diffraction field of each sampled light point and other descriptions can be thought as grouping with point-cloud by different way. The paper focuses on devising a computation method of 3D Fresnel field which is based on Fresnel diffraction field propagation reversibility. The proposed method combines the reversibility of Fresnel propagation and the requirement of sampling spacing by Nyquist criterion, i.e. to find the best space positions to optimize the number of sampling points and the reconstruction for the 3D Fresnel field. The method can be applied to reduce the computational complexity and improve computational efficiency.

An application example of precision photoelectric 2D-turntable for aiming device baseline variation detection is proposed in this paper, the optical measurement method is also expounded and the design scheme of automatic digital photoelectric 2D-turntable with high precision is supported. Because the supporting framework is the key component and the main bearing component of two-dimensional turntable, its strength and stiffness will directly affect the adjustment accuracy and stability property, the variable density topology optimization is applied to optimize the structure of supporting framework. The quality of supporting framework reduces by 20%, the displacement of the center of shafting mass under gravity loads is less than 0.05mm. The experimental results indicate that adjustment error of the photoelectric 2D-turntable is less than 0.05mil, repetitive positioning accuracy is more than 0.01mil which meets the design requirements of high precision adjustment accuracy or stability.

Freeform optics especially Continues Phase Plate, are greatly demanded in high power laser systems. Fabrication of them with high efficiency and low sub-surface damage becomes a major challenge. Atmospheric pressure plasma processing using radicals produced by plasma torch, which has strong potential for machining freeform optics with millimeter and sub-millimeter spatial resolution, is proposed. This paper presents a novel plasma torch designed for fabricating freeform optics. This integral compact torch is comprised of needle electrode and micro-hole electrode. Millimeter-scale plasma jet of different size can be obtained by changing the micro-hole electrode. To analyze the process distribution of process gas of the jet flow, flow simulation is performed using COMSOL Multiphysics software. A set of single factor experiments are conducted to reveal the relationship between removal characteristics and flow rate of He, CF₄ and O₂. The removal rate with adding O₂ increases 7 times of that without O₂, and the spectrum change of the plasma jet is observed. It indicates that O₂ improves removal rate through consuming existing CF_x to produce more F radicals. The removal rate and full width at half maximum (FWHM) of typical removal function is about 19 μm/min-2.2 mm and 18 μm/min-1.1 mm respectively.

Binary pattern defocused projection is a promising method of measuring 3D shapes. However, deep or long-distance defocus prevents high-accuracy 3D measurement. The triangle pattern is preferred because of its slight defocus and ability to overcome the nonlinear gamma. Thus, a novel method combining triangle pattern slight defocus with phase shifting is proposed. The proposed method has two merits: (1) Compared with the sinusoidal pattern, the proposed method can overcome the nonlinear gamma. (2) Compared with the binary pattern, it has the advantage of slightly defocusing to an ideal sinusoidal pattern in a short distance. Thus, the measurement error caused by nonlinear gamma and deep defocus is reduced. The RMS error of the proposed method is <0.03 mm. Theory analysis and experiments demonstrate the feasibility and superiority of the proposed method.

Zinc sulfide is a kind of typical infrared optical material, commonly produced using single point diamond turning (SPDT). SPDT can efficiently produce zinc sulfide aspheric surfaces with micro-roughness and acceptable figure error. However the tool marks left by the diamond turning process cause high micro-roughness that degrades the optical performance when used in the visible region of the spectrum. Magnetorheological finishing (MRF) is a deterministic, sub-aperture polishing technology that is very helpful in improving both surface micro-roughness and surface figure.This paper mainly investigates the MRF technology of large aperture off-axis aspheric optical surfaces for zinc sulfide. The topological structure and coordinate transformation of a MRF machine tool PKC1200Q2 are analyzed and its kinematics is calculated, then the post-processing algorithm model of MRF for an optical lens is established. By taking the post-processing of off-axis aspheric surfacefor example, a post-processing algorithm that can be used for a raster tool path is deduced and the errors produced by the approximate treatment are analyzed. A polishing algorithm of trajectory planning and dwell time based on matrix equation and optimization theory is presented in this paper. Adopting this algorithm an experiment is performed to machining a large-aperture off-axis aspheric surface on the MRF machine developed by ourselves. After several times’ polishing, the figure accuracy PV is proved from 3.3λ to 2.0λ and RMS from 0.451λ to 0.327λ. This algorithm is used to polish the other shapes including spheres, aspheres and prisms.

Texture depth is defined as the deviations of the road surface profile from the datum plane. It is currently assessed by two methods--sensor measured texture depth (SMTD) and sand patch method (SPM). Many researchers did lots of experiments to study the correlation between these two methods, but ignored the waveform characteristic of the road surface profile. A mathematical model of the road surface profile was built in this paper to calculation of texture depth and compare the two methods. This paper studied the statistical relationship between sensor measured texture depth and sand patch method in different waveform characteristics, and found out that the frequency is the main factor. The results show that the two methods have excellent correlation at the same frequency, and the correlation coefficient R² is equal to 1. Plates with same frequency were designed to conducted comparison experiments. The result verify the above conclusion. It shows good correlation between the laser detection technology and the volumetric patch technique. Since manufacturers mainly use sand patch method for experiments, the result provides a theoretical basis and technical support for factory inspection. Also, it can be used to get the characteristics of the pavement structure in return.

In order to collect a wide angle range light to receive the collimating beam of a small divergence angle, a highly efficient, compact, TIR collimating system has been designed and optimized. The collimating system adopts a hybrid structure with TIR style. First, calculate the initial structure of the collimating system according to Snell’s law and equal focal length principle. Then optimize the initial structure using Lighttools optical design software. Finally, the best LED collimating system has been successfully designed. According to the results of the design, the semi-diameter of the TIR collimating system is 20mm, the diameter is 25mm. The collimating angle is 1.5°. With the light absorption loss of the material and reflection loss of the interface have already been fully considered，the light energy utilization rate is as high as 89.5%. The initial structure of TIR-type LED collimator is designed by Snell’s law and equal focal length principle, and then it is optimized by the Lighttools optical design software, so that light energy utilization ratio and uniformity of illumination in the target surface are improved. In addition, TIR-type collimating system, which is small and easy to use, not only has a high light energy utilization ratio but also a compact structure.

The cost of photovoltaic power generation can be saved and efficiency will be improved by the concentration optics system. However, the non-uniformity of illumination distribution on the photovoltaic cells of the current Fresnel concentrators will reduce the photoelectric conversion efficiency and decrease the service life of the cell even damage the cell. This paper presents the design and simulation a novel nonimaging Fresnel concentrator, then comparatively analyses the performances of the conventional Fresnel concentrator. The novel nonimaging Fresnel concentrator has been design according to the diffused focal points method to improve optical efficiency and illumination uniformity. The novel Fresnel concentrator achieves high concentration efficiency 82.20%, and high uniformity 89.23% in the scope ±4mm of the concentration spot which can improve photoelectric conversion efficiency of photovoltaic cells and prevent the photovoltaic cells from being damaged.

In recent years, more and more attention has been paid to the bionic structure and functional materials. The theoretical research and fabricating ways of the Super-hydrophobic surface have sound achievements. However, the existing methods largely depend on the precision of the equipment and complex chemical substances, and it is hard to ensure the consistence of the material surface. Therefore, construction of microstructure on the surface of the material by using the method of mechanical processing to make the scale of the Super-hydrophobic surface to promote the popularization and application of Super-hydrophobic surface is of great significance. In order to put forward the innovative microstructure and to provide theoretical basis for the subsequent mechanical processing, based on the analysis of the classical theory of Super-hydrophobic, the super-hydrophobic film was by sol gel method. To explore the effects of different ratio of materials on the hydrophobicity, a micro/nano-structured super-hydrophobic coating was obtained by coating a film improved by hexamethyldisilazane (HMDS) after a film improved by polyethylene glycol (PEG) was coated. The microstructure of bilayer films is analyzed, and the double-layer film structure is simplified to design two kinds of microstructure models. For the design of the two models based on the Wenzel and Cassie equations, a roughness factor is adopted to establish the quantitative relationship between the contact angle and the microstructure parameters, and the microstructure parameters is also analyzed by using MATLAB software, and hence the optimized microstructure parameters is obtained.

Modified antireflective thin films for optical crystals are developed by sol gel chemistry. Hexamethyldisilazane is added to silica sol to prepare modified sol by the Stöber method. The particle size distribution of the modified sol is found to have good uniformity, with an average particle diameter of about 42.14 nm. This sol can be used to prepare antireflective films with low refractive index of about 1.2. Homogeneous double layered films of antireflective and moisture resistant properties are demonstrated to coat small square sized KH₂PO₄/KD₂PO₄ crystals through a combination of dip and spin coating. The modified antireflective films display residual reflectivity close to zero, and laser induced damage threshold of 10.9 J/cm² (pulse wavelength: 355nm, pulse width: 3ns) measured by raster scan method.

Absorption of edge-cladding Cu-glass for the strong amplified spontaneous emission of Nd-glass disk will produce a large rise for the temperature and thermal stress near the cladding interface between Cu-glass and Nd-glass. According to the calculation for amplified spontaneous emission of Nd-glass and thermal stress along the thickness of Cu-glass, which is produced in our lab, the relations among temperature rise, thermal stress, CuO doping concentration and thickness of cladding Cu-glass, are discussed in detail. If using 0.10% CuO doping instead of 1%, which was used in the previous time, the maximum temperature will decrease from 46K to 13K and the thermal stress will decrease from 4.0 MPa to 0.8 MPa. Our edges cladding experimental results, obtained by the low CuO concentration edge cladding glass, are consistent with the inferences and validated in the SG series laser systems.

Aiming at the problem that the damage threshold of gold coated grating is relatively low, a dielectric film is considered on the gold coated gratings as a protective layer. The thickness range of the protective layer is determined under the prerequisite that the diffraction efficiency of the gold coated grating is reduced to an acceptable degree. In this paper, the electromagnetic field, the temperature field and the stress field distribution in the grating are calculated when the silica and hafnium oxide are used as protective layers, under the preconditions of the electromagnetic field distribution of the gratings known. The results show that the addition of the protective layer changes the distribution of the electromagnetic field, temperature field and stress field in the grating, and the protective layer with an appropriate thickness can improve the laser damage resistance of the grating.

According to a study in KDP crystal growth and performance, it’s found that the impurity content of potassium dihydrogen phosphate crystal by batch production affects directly the growth rate and optical properties of the KDP crystal. Through research on a variety of materials production methods, it’s found that there’re seldom reports on impurity removing technology by physical methods. This project studied the key process parameters and control factors on the batch production of potassium dihydrogen phosphate raw material. By modification and adjusting the process parameters, the quality of KDP crystal materials is improved.

The subsurface damage (SSD) introduced by manufacturing procedures are the important factors affecting mechanical and optical properties of the high-precision optical components. In this paper, we investigated the relationships between the size of SSD’s micro crack and optical properties by studying on the influence of grinding process parameters (average abrasive size, grinding force, wheel speed, grinding depth) on the optical properties (transmittance, absorbance, reflectance) of high-precision optical components first, and then determining the micro crack’s size under the grinding process parameters. Results indicate that with the increase of average abrasive size, grinding force or grinding depth, the transmittance of high-precision optical components decreases while the absorbance and reflectance increase. However, as the wheel speed increases, the transmittance of high-precision optical components increases while the absorbance and the reflectance decrease. Combining these results with the influence of grinding process parameters on the size of micro crack, it can be found that with the increase of micro crack’s size, the transmittance will decrease, while the absorbance and the reflectance will increase.

Since the difference between the film and the quartz, there are problems in metallization process such as low bonding strength, poor wettability and the film stress; combined with the actual situation, carried out a series of exploration of the above problems, take different measures to solve the practical problems.

Hafnium oxide, hafnium crystal bar and high-purity hafnium were prepared using extraction separation, reduction, electrolytic refining, iodide refining and electron beam melting process by General Research Institute for Nonferrous Metals. A hundreds-kilogram production line has been built. The purity of the high-purity hafnium was Zr/(Zr+Hf) <0.3wt% and Zr+Hf>99.99wt%, which enables a high laser induced damage threshold.

With method of fixing wire in the high power pulsed xenon lamp tube, an experimental device of double lamp series was established to simulate the actual working environment of the xenon lamp. The experimental results show that the thermal damage with the pre delay time of 150μs is much more serious compared with the pre delay time of 250μs. The reason could be that the metastable particles formed by pre discharge are uneven with the former. The tube pale first appears near the left lamp anode and the right lamp cathode. The possible reason is that bifurcates and shifts of the plasma discharge channel are affected by the wire. The test results show that the main reason of thermal damage is that the temperature of discharge plasma is uneven inside the tube. By improving the structure of the lamp box and optimizing the pre delay time, the discharge plasma temperature can be decreased for the avoidance of the thermal damage.

Owing to damage, thermal issues, and nonlinear optical effects, the output power of fiber laser has been proven to be limited. Beam combining techniques are the attractive solutions to achieve high-power high-brightness fiber laser output. The spectral beam combining (SBC) is a promising method to achieve high average power output without influencing the beam quality. A polarization independent spectral beam combining grating is one of the key elements in the SBC. In this paper the diffraction efficiency of the grating is investigated by rigorous coupled-wave analysis (RCWA). The theoretical -1st order diffraction efficiency of the grating is more than 95% from 1010nm to 1080nm for both TE and TM polarizations. The fabrication tolerance is analyzed. The polarization independent spectral beam combining grating with the period of 1.04μm has been fabricated by holographic lithography - ion beam etching, which are within the fabrication tolerance.

The surface chemical composition and atomic emission spectroscopy of F atoms and CF₂ molecules involved in the processing of Atmospheric Pressure Plasma Jet (APPJ) produced from CF₄ precursor has been explored. The XPS spectra illustrated that small amount of radicals including C-CF_n and CF-CF_n could be introduced onto the fused silica surface during the CF₄ plasma process, the fluorocarbon radicals were generated during CF₄ plasma ionization. Moreover, the relative concentrations of excited state species of F atoms and CF₂ molecules, which play significant role in remove and fluorocarbon radicals, were acquired for CF₄ plasma. The densities of F atoms increased dramatically with increasing applied RF power, whereas CF₂ molecules decreased monotonically over the same power range, the subsequent electron impacted decomposition of plasma species after CF₄ precursor fragmentation. The spectrum of the F atoms and CF₂ molecules fallowed the same tendency with the increasing concentration of gas CF₄, reaching the maximum at the 20sccm and 15sccm respectively, and then the emission intensity of reactive atoms decreased with more CF₄ molecules participating. Addition certain amount O₂ into CF₄ plasma resulted in promoting CF₄ dissociation, O₂ can easily react with the dissociation product of CF₂ molecules, which inhibit the compound of the F atoms, so with the increasing concentration of O₂, the concentration of the CF₂ molecules decreased and the emission intensities of F atoms showed the maximum at the O₂/CF₄ ratio of 20%. These results have led to the development of a scheme that illustrates the mechanisms of surface chemistry reaction and the affection of plasma parameters in CF₄ plasma systems with respect to F and CF₂ gas-phase species.

With the progress of high power laser system, the specifications of the large-aperture optics on the low-spatial-frequency wavefront, mid-spatial-frequency wavefront, high-spatial-frequency wavefront all meet stricter requirements. To the mid-spatial-frequency wavefront, it has been researched less than others. The influence factors of the mid-spatial-frequency wavefront PSD1 error for large-aperture mirrors are analyzed in this work. The results show that the influence factors of the mid-spatial-frequency wavefront is different with the low-spatial-frequency wavefront. PV error depends on the peak and vale of film surface，Grms error is affected by the big amplitude wave of film surface, and PSD1 error is mainly caused by the small frequency wave of film surface. So it is the key to controlling the PSD1 error for large-aperture mirrors that reducing small frequency wave of film surface.

The a-C:H films were deposited on glasses with different substrate thickness (rising from 2mm to 26mm) by Plasma Enhanced Chemical Vapor Deposition (PECVD). The effect of substrate thickness to the deposition rate, structural variations of films was investigated by surface morphology device and Raman spectroscopy. The results show that the deposition rate, H contents of films increase, meanwhile, I(D)/I(G), G peak position decrease and all of them show strong linear relation with the increasing substrate thickness. The a-C:H film with the highest thickness presents the highest deposition rate (37.7nm/s), nanohardness (20.2GPa), elastic modulus (118.8GPa) and lowest friction coefficient (0.266).

A KTP EOPO pumped by an AO Q-switched and SESAM mode-locked Nd³⁺: GdVO₄ laser is experimentally realized. The cavity is designed to satisfy synchronously pump. The signal trace and output powers from the OPO are experimentally measured. Based on the experiment, a dynamical rate-equation model is firstly set to simulate the operation of the Q-switched and mode-locked OPO. The theoretical values from the rate equations agree with the experimental results well. The developed model explains the behavior, which is helpful to system optimization.

The laser damage character of fused silica is studied experimentally. Firstly the distribution of the defects is presented. Furthermore, the relevancy of the laser damage character and the defects is discussed. Finally, the fluorescence of damage-occurring is explained. From the result, the way to ameliorate the laser damage character by controlling the defects is given.

An experimental study of the ignition and combustion characteristics of Al/Mg fuel-rich propellant at lower ambient pressures was performed. Measurements were obtained in a sealed vessel capable of reaching pressures as low as 0.1 atm with the application of vacuum pump. The ignition delay time was obtained by photodiodes which monitor the laser signal and flame signal; the linear burning rate of propellant was obtained by processing the continuous high-speed video images. The experimental results show that the reduction in pressure caused a longer ignition delay time, this dependence will get weaker as the externally applied heat flux increased; the linear burning rate reduced with the reduction of pressure, even reduced about 47% at 0.1atm compared to constant pressure.

High reflection films for 800nm picoseconds laser system requires broad bandwidth, which is usually about ±50nm, or even to ±70nm, and a high laser damage threshold is needed at the same time. Multilayer dielectrics using three materials Nb₂O₅/SiO₂-HfO₂/SiO₂ were fabricated by electron beam evaporation. Benefit from its high refractive index of Nb₂O₅ and the high damage threshold of HfO₂ films, the multilayer dielectrics were prepared successfully, which have more than 99.5% reflectance within bandwidth larger than 140nm around the center wavelength of 800 nm. The laser damage characteristics of the films at 150ps, 1Hz were studied, and the damage mechanism was analyzed.

In order to achieve the high precision fabrication of the large-aperture off-axis Wedged Focus Lens (WFL) for high power laser device, the involved fabrication technologies including the ultra precision grinding, the high efficiency polishing and the deterministic polishing, have been explored in this paper. Firstly, based on the configuration characteristic of WFL, the parallel grinding theory and the calculation method of CNC program were introduced. Secondly, the main factors affecting the removal efficiency were investigated and analyzed by orthogonal approach experiment in the high efficiency polishing process, which can be used for the quality control. Then, the methods for maintaining the stability of removal function and restraining the surface ripple were investigated during deterministic polishing process. Finally, a 430mm×430mm off-axis Wedged Focus Lens was manufactured using the above technologies, and the results indicated that, after polishing, the P-V, RMS, GRMS, PSD RMS1, PSD RMS2 and Rq are 0.097λ, 0.012λ (λ=632.8 nm), 5.851 nm/cm, 2.325 nm, 0.541 nm and 0.21 nm, respectively, which meet the requirement of high power laser device. Consequently, the effectiveness of the proposed key technologies is proved.

Because of its excellent optical performance, the fused silica is widely used in laser industry. In addition, the fused silica can withstand high power laser, due to its pure component, and the performance is most outstanding within all types of glasses. So fused silica can be used for optical lens in high power laser field.

From the manufacturing process stand point, the fused silica can be categorized to four types: type Ⅰ, type Ⅱ, type Ⅲ, and type Ⅳ. The fused silica of type Ⅰand type Ⅱ is made through melting silica sand in graphite furnace or oxyhydrogen flame. There are many defects in these types of fused silica, for example, the air bubbles, inclusions and metallic impurity. The other two types are made by synthetic reaction of SiCl₄ with water in oxyhydrogen or plasma flame. Both type Ⅲ and Ⅳ have excellent performance in transmittance and internal quality. However, type Ⅳof fused silica has disadvantage in small aperture and overall high manufacturing cost.

Take the transmittance and internal quality into consideration, the type Ⅲ fused silica is the most suitable for large-aperture lens, and can withstand high power laser. The systemic studies of manufacturing process were done to improve the performance of type Ⅲ fused silica in various areas, for instance, the optical homogeneity, the stress birefringence, the absorption coefficient and the damage threshold. There are four steps in manufacturing process of type Ⅲ fused silica, ingot production, reshaping, annealing and cold-working. The critical factors of ingot production, like the flame of burner and the structure of furnace, were deeply studied in this paper to improve the performance of fused silica.

On the basis of the above research, the performance and quality of the fused silica measured up to advanced world levels. For instance, the result of optical homogeneity can be controlled to 2～5 ppm, the stress birefringence is better than 4 nm/cm, the absorption coefficient is about 5.971ppm cm^-1 (1ω), the damage threshold is greater than 80, 25 and 23 J/cm² with the wavelength at 1064, 532 and 351nm respectively, the bandwidth used for measuring is 3ns.The fused silica has already been used in the area of high power laser facilities, aerospace industry, primary lens of interferometer based on its excellent performance.

The ion-beam sputtering deposition is a good technique for making low scattering coatings. In this work, the Ta₂O₅ thin films as the oxygen flux (15-35sccm) were prepared on the K9 glass using the single ion-beam sputtering. As the oxygen flux increased, the thickness of films with the same deposited time decreased from 936.67nm to 837.87nm. The refractive index was 2.075 in 1000nm at 30 sccm. The stress increased along with the increasing of oxygen flux. In the work, the compressive stress increased from 319.55 Mpa to 410.92 Mpa.

This article studies the long-term stability of Na、Mg、Cr、Mn、Fe、Co、Cd、Ba、Pb in the matrix effect of potassium dihydrogen phosphate tested on ICP-MS Model X-series II manufactured by ThermoFisher. The test result proves good long-term stability and reliable analysis of the instrument.

The response characteristics of the pitch polishing pad under the pressure of conditioner is the key factor which affect the control efficacy of surface figure in annular polishing. The effect of the environmental temperature and humidity, rotation speed of the pad, uploading ratio and eccentricity of the conditioner on the response characteristics of pitch polishing pad were experimental researched. To this aim, a control system of the environmental temperature and humidity on the 2.8m-aperture annular polishing machine is established. The control precision of the local environmental temperature upon the pad is up to ±0.1℃, and the control precision of humidity is up to ±1% RH. The experimental results indicate that the matching degree of the pad and the conditioner decides the changing rule of the surface figure of workpiece with the eccentricity of the conditioner. The new adjustable parameters including the environmental temperature and humidity and the uploading ratio of the conditioner were introduced to change the matching degree and improve the controllability of the of the surface figure. Under the optimized process, the long-term stability of the surface figure of the meter-scale optical element is realized using the 2.8m annular polishing machine, which is an important step for the final realization of the deterministic processing in the large-aperture annular polishing.

Higher accuracy of optical surface measurement is needed with the rapid development of optical industry and technology, especially in the field of optical manufacture and optical metrology. Fizeau interferometery is widely recognized as one of the most important measurement techniques currently in use. Results of the Fizeau interferometeric testing contain the reference surface errors and test surface errors. The test accuracy is restricted by the error of reference surface. As a result, so-called absolute flatness testing technology must be used to eliminate the system error such as reference surface error and higher accuracy of the surface profile testing. In this paper, the theory formula of even and odd functions is deduced, and the method are programmed for simulation. Based on HOOL phase-shifting interferometer, experiments are done to achieve high accuracy flatness measurement. The experiment shows that with high-accuracy interferometer, absolute flatness testing technology can effectively calibrate reference surface and improve the accuracy of flatness surface testing. An important result of this experiment is that the accuracy of the test surface can be reached λ/50.

A high-efficiency, high-repetition-rate burst-mode 1064 nm laser under pulsed 878.6 nm laser diode pumping is demonstrated. Pulses at repetition rates ranging from 10 kHz to 100 kHz are produced during the time period of 1 ms pumping duration by using an acousto-optical Q-switch. The maximum pulse burst energy of 44 mJ at 10 kHz is obtained at the incident pump power of 108.5 mJ, yielding an optical-to-optical efficiency of 40.5%. The shortest pulse width at 10 kHz is 9.4 ns at the maximum pump energy of 108.5 mJ. The peak powers are estimated to be ~468.1 kW and 30.1 kW at 10 kHz and 100 kHz in the burst-mode oscillator.

Fundus camera is widely used in screening and diagnosis of retinal disease. It is a simple, and widely used medical equipment. Early fundus camera expands the pupil with mydriatic to increase the amount of the incoming light, which makes the patients feel vertigo and blurred. Nonmydriatic fundus camera is a trend of fundus camera. Desktop fundus camera is not easy to carry, and only suitable to be used in the hospital. However, portable nonmydriatic retinal camera is convenient for patient self-examination or medical stuff visiting a patient at home. This paper presents a portable nonmydriatic fundus camera with the field of view (FOV) of 40°, Two kinds of light source are used, 590nm is used in imaging, while 808nm light is used in observing the fundus in high resolving power. Ring lights and a hollow mirror are employed to restrain the stray light from the cornea center. The focus of the camera is adjusted by reposition the CCD along the optical axis. The range of the diopter is between -20m^-1 and 20m^-1.

The radiation characteristics in millimeter-wave band of the metal objects are complicated particularly those with complex three-dimensional structures. The complicated electromagnetic environment, in which the stereoscopic metal objects reflect the radiation energy in all directions with arbitrary incident angles, makes this problem even more challenging. In this paper, the surface panel method and the ray tracing theory are used to analyze the bins of the stereoscopic metal targets surface and their corresponding radiation sources in the reflection path. In addition, in 3mm band the radiometric images of the metal ball and the metal column are given by practical measurements. By comparing the single radiation scanning curves of the selected metal targets, the influence of the three-dimensional structures on the brightness temperature was analyzed and verified. Furthermore, the differences of the radiation patterns of different stereoscopic structures are also summarized.