This PDF file contains the front matter associated with SPIE Proceedings Volume 8197, including the Title Page, Copyright information, Table of Contents, Introduction, and Symposium committee listing.

This paper presents the work of using advanced optical measurement techniques to implement stack gas emission monitoring and process control. A system is designed to conduct online measurement of SO₂/NO_X and mercury emission from stacks and slipping NH₃ of de-nitrification process. The system is consisted of SO₂/NOX monitoring subsystem, mercury monitoring subsystem, and NH₃ monitoring subsystem. The SO₂/NO_X monitoring subsystem is developed based on the ultraviolet differential optical absorption spectroscopy (UV-DOAS) technique. By using this technique, a linearity error less than ±1% F.S. is achieved, and the measurement errors resulting from optical path contamination and light fluctuation are removed. Moreover, this subsystem employs in situ extraction and hot-wet line sampling technique to significantly reduce SO₂ loss due to condensation and protect gas pipeline from corrosion. The mercury monitoring subsystem is used to measure the concentration of element mercury (Hg⁰), oxidized mercury (Hg²⁺), and total gaseous mercury (Hg^T) in the flue gas exhaust. The measurement of Hg with a low detection limit (0.1μg/m³) and a high sensitivity is realized by using cold vapor atom fluorescence spectroscopy (CVAFS) technique. This subsystem is also equipped with an inertial separation type sampling technique to prevent gas pipeline from being clogged and to reduce speciation mercury measurement error. The NH₃ monitoring subsystem is developed to measure the concentration of slipping NH₃ and then to help improving the efficiency of de-nitrification. The NH₃ concentration as low as 0.1ppm is able to be measured by using the off-axis integrated cavity output spectroscopy (ICOS) and the tunable diode laser absorption spectroscopy (TDLAS) techniques. The problem of trace NH₃ sampling loss is solved by applying heating the gas pipelines when the measurement is running.

The invention of the femto-second frequency comb laser has revolutionized the field of high-resolution spectroscopy, by providing very accurate reference frequencies in the optical domain, acting as a 'frequency ruler'. Similarly, a frequency comb can be viewed as a ruler for distance measurement, which is based on the fact that the vacuum distance between subsequent pulses is known with the accuracy of the used time standard. We have recently demonstrated absolute distance measurements using a FC laser applying a cross-correlation technique, which was supported by a theoretical and a numerical study on the formation of cross-correlation in dispersive media. In this contribution a measurement scheme based on dispersive (spectral) interferometry is presented. For the measurement of distances up to 50 meter, sub-micrometer accuracy is achieved.

Binocular stereo vision system has been widely used in 3D shape and deformation measurement. Many experimental systems and instruments have been developed based on this method. To realize the stereo vision measurement, the measured surface must carry some image "structures", such as points, fringes, or even random speckles, so that the parallax of the dual camera could be obtained by matching the "structures". However, for on-line inspection of black surface, the general projection methods are impossible to produce the appropriate "structures". In this paper a new binocular stereo vision system based on the laser dot matrix projection is presented. The laser projector is made up of two pieces of orthogonal fine grating and laser diode, when the laser beam was projected to the grating, a laser dot matrix will be formed and this high contrast dot matrix could be imaged on any surfaces, including the black surfaces. Furthermore, the image quality is greatly improved by mounting a red color filter (if a red laser) on the camera lens. Finally, a 3D shape measurement of a black cylinder is completed to verify the validity of the system.

Optical non-contact measurement has many advantages, which has been widely used in the precise size measurement. Since the precision axle hole's inner diameter is small, the measuring axis optical system cannot be placed into the axle hole. As a result, the optical non-contact measurement is difficult to be applied in the occasion above. In this paper, a set of optical system based on off-axis imaging principle that applied to small axle hole's inner diameter measurement is designed. According to the Scheimpflug principle, the relationship of object plane tilt and image plane tilt is derived in this paper. To meet the requirement of measurement accuracy, an off-axis imaging system with a suitable magnification is presented. The off-axis imaging optical system cooperating with the fiber collimator and the PSD can attain 2μm measurement accuracy.

To track a projectile and then to obtain its flying attitude is very important for the design and control of high-speed projectile. In order to measure the attitude of projectile, a high-speed binocular stereo vision system with digital image correlation technique (H3D-DIC) is designed and constructed by using two different types of high-speed cameras. And, the correlation program which is able to correct image magnification and pixel size parameters of different types of cameras is completed. Finally, an experiment to track a flying arrow is performed and the profile of the arrow body is measured. Based on the experimental result, the flying attitude of the flying arrow is analyzed. The experiment verifies validity of the H3D-DIC system.

A novel fiber optic sensor using 'BOF' has been developed by vapor deposition of dielectric BPF on an end face of a single-mode fiber, as BPF on fiber-end (BOF), of which the reflection spectrum varies according to its temperature and pressure. The spectrum shift is obtainable as the ratio of reflectance at both sides of the BOF center wavelength, which is derived from the dual wavelength impulse responses of the sensor network obtained on the PN code correlation scheme. It is called dual wavelength push-pull ratiometric reflectometry (DWPR). The resulting multipoint temperature and pressure sensing operation will be demonstrated.

In response to the accuracy of most autocollimator measurement is not high, and limited to one-dimensional static measurement., we designed a kind of high-precision photoelectric self-collimation measurement system which based on position sensitive detector(PSD). The system uses a return-type optical path to reduce equipment size, and the use of neural network based on the PSD for the non-linear correction. When the distance is 10m, it can achieve the measurement range ± 4', full-range measurement error of less than 0.1", measurement resolution of less than 0.01" and other technical indicators.

Rapid progress of exposure systems for IC manufacturing is pushing their performance from sub-micrometer to nanometer and catadioptric projection optics have been developed to fulfill this trend. The catadioptric projection optics will produce an annular wavefront. In our system with catadioptric projection optics, the Hartmann wavefront sensor is employed for the test. The wavefront reconstruction method is essential to the accuracy of inspection. For typical annular wavefronts with smaller and larger obscuration ratios, the wavefront reconstructed via modal method with Zernike annular polynomials, modal method with Zernike circular polynomials and zonal method are compared. Simulation results show that both the modal method with Zernike annular polynomials and zonal method are qualified to guarantee the accuracy of reconstruction in both cases. While the modal method with Zernike circular polynomials fail in the case of larger obscuration ratios. The wavefront reconstruction with different terms of Zernike annular polynomials, Zernike circular polynomials and the wavefront fit following the zonal method with a different number of Zernike polynomials are conducted as well.

In the application to nanometre resolution lithography of the metallic near-field superlens, the image quality becomes a critical issue. Fundamental Fourier optics is applied to analyze the image system. The transfer function is computed with the transfer matrix method, the Surface Plasmon Polariton (SPP) resonance and the SPP waveguide theory. However, as the scattering of the object nano-structure involving the solution of the Maxwell's equations, so that the object function is in general unknown, and the impulse response is less likely useful for computing the image. Especially, metal object may induce the electrical dipoles, which launch the SPP and act as sources of radiation. The superlens may be optimized based on the transfer function using the long-range SPP mode cut-off technique, the genetic algorithm and other techniques in order to improve significantly the image quality. Design examples are presented, and confirmed by the real image computed with numerical simulation using the FDTD method.

Waveguide grating filter with an antireflective surface is designed by using the equivalent homogeneous thin-film model. The spectral properties are investigated by using the rigorous method based on the calculated parameters. It is shown that the equivalent homogeneous thin-film model may provide a reliable approximation in estimating the resonance locations of the filters even for the surface-relief grating structure. The validity of the design model decreases with the increase of the refractive index contrast of the grating layer for a fixed grating filling factor.

In this paper, the effect of the relative microstructure heights error on the diffraction efficiency of multilayer diffractive optical elements (MLDOEs) is considered. Based on the relationship of diffraction efficiency and diffractive microstructure height, the analysis result of the relative microstructure height error on the diffraction efficiency of MLDOEs for 8-14μm far infrared optical system was present. It is shown that the diffraction efficiency over the whole waveband is above 98.94% for double-layer DOEs when the two relative microstructure heights error are equal and both controlled within ±2%. However, the diffraction efficiency drops quickly when the two relative microstructure heights error changed in the opposite sign. The analysis result can be used for analyzing the effects of microstructure heights error on diffraction efficiency for MLDOEs working in infrared optical system.

We propose a high-contrast coronagraph based on the step transmission filters for the direct imaging of an Earth-like exoplanets. To demonstrate the performance of the coronagraph, two 50-step transmission filters were manufactured and several experiments have been performed. At present, the coronagraph can reach a high contrast around 10^-7 at an inner angular distance of ~2λ/D in the visible wavelength. Such a coronagraph should be installed on an off-axis space telescope which will be promising for the direct imaging of an Earth-like exoplanet in the future.

Non-Uniformity Correction (NUC) is a key technology for Infrared Focal Plane Array (IRFPA) real-time image processing system. In this paper, an IRFPA real-time two-point calibration (TPC) algorithm hardware system was designed. The system use CycloneIII-EP3C120F780 FPGA of the ALTERA as the controller, and has following features: simple structure, high precision, stability, portability, and real-time. The timing simulation and measurement for the developed hardware system verified the effectiveness of the scheme.

Gamma correction is an important processing in reproduce images information realizing of video source. In order to improve the image sharpness of the OLED micro-display, a Gamma correction system was established to compensate for the gray scale distortion of the micro-display which is caused by the difference between the optical and electrical characteristic property. Based on the North OLEiD Company's 0.5 inch OLED, We proposed a Gamma correction system to converts 8 bits input signal into 9 bits displayed on the OLED. It used Microchip as the MCU and the master of the I²C serial bus, Development of the hardware system measurement verified the correction of VGA and CVBS video input and the picture quality also apparently improved.

Almost every aspect concerning the design of modern panoramic lenses brings new challenges to optical designers. Examples of these include ray tracing programs having problems finding the entrance pupil which is moving through the field of view, production particularities due to the shape of the front lenses, ways of tolerancing these systems having strong distortion, particular setups required for their characterization and calibration, and algorithms to properly analyze and make use of the obtained images. To better understand these modern panoramic lenses, the Optical Engineering Research Laboratory at Laval University has been doing research on them during the past few years. The most significant results are being presented in this paper. Controlled distortion, as in commercial panomorph lenses (Immervision), is used to image a specific part of the object with more pixels than in a normal fisheye lens. This idea is even more useful when a zone of interest vary in time with dynamically adjustable distortion as in a panoramic locally magnifying imager. Another axis of research is the use of modern computational techniques such as wavefront coding in wide-angle imaging systems. The particularities of such techniques when the field of view is large or with anamorphic imagers are considered. Presentation of a novel circular test bench in our laboratories, required to calibrate and check the image quality of wide-angle imaging system, follows. Another presented setup uses a laser and diffractive optical elements to compactly calibrate wide-angle lenses. Then, a discussion of the uniqueness in tolerancing these lenses, especially the front elements due to the large ratio between lens diameter and entrance pupil diameter, is included. Lastly, particularities with polarization imaging and experiments of triangle orientation detection tests before and after unwrapping the distorted images are briefly discussed.

HMD (head-mounted display) is an important virtual reality device, which has played a vital role in VR application system. Compared with traditional HMD which cannot be applied in the daily life owing to their disadvantage on the price and performance, a new universal and smart Helmet-Mounted Display of large FOV uses excellent performance and widespread popularity as its starting point. By adopting simplified visual system and transflective system that combines the transmission-type and reflection-type display system with transflective glass based on the Huggens-Fresnel principle, we have designed a HMD with wide field of view, which can be easy to promote and popularize. Its resolution is 800*600, and field of view is 36.87°(vertical)* 47.92°(horizontal). Its weight is only 1080g. It has caught up with the advanced world levels.

This paper presents a miniaturized CMOS camera for high-definition (HD) medical electronic endoscope system with resolution of 1.3 MegaPixel. LVDS technology is used for image data stream transmission between the sensor and the HD image workstation to realize a long distance, high speed, high signal integrity and low noise system. Considering the real-time video image processing and the complexity of the design of HD image workstation, four solutions for medical electronic endoscope systems, namely USB based image acquisition system, PCIe acquisition data board based method, ARM embedded system based solution and DSP based electronic endoscope system have been proposed, analyzed and compared with each other. We found that the four solutions have their own advantages and disadvantages. Taking into account the strong control capacity of ARM, powerful data processing ability and high operating speed of DSP, good portability and other factors, we decided to use ARM + DSP embedded based system.

In this paper, we describe a new kind of micro fluidic channel used in suspension biochip detection system that is different from cytometry. The key indexes of the detection system are space resolution and sensitivity, which both depended on optical system and filtering system. At first, the key factors which have great effect to space resolution have been analyzed. Secondly the filtering system of suspension array is analyzed. At last the transmission ration curve of the filters used in our detection system has been tested in detail. The optimization design suspension biochip is also obtained.

Liquid crystal modulator is an active optical component that is promising to replace traditional passive optical components. For high-contrast imaging coronagraphs that are used for direct imaging of extra-solar planets, passive coronagraph optical components are often adopted. It is impossible to actively optimize such a coronagraph system to achieve its best performance. Thus we've proposed a novel high-contrast imaging coronagraph which uses a liquid crystal array (LCA) for pupil apodizing. In our test, the LCA is well calibrated for amplitude errors and amplitude non-uniformity with the entire coronagraph optics. Close-loop compensations are applied according to the amplitude calibration results. By doing so, a contrast of 10^-4 or 10^-5 can be achieved in an angular distance down to 3~5λ/D, which can be used for the direct imaging for young and Jupiter-like planets. The contrast can be further improved if a deformable mirror (DM) is deployed to correct wave-front errors induced by the LCA and the coronagraph optics.

When branch points are present in laser beam wave-front during the propagation in turbulence, the adaptive optics system for atmosphere turbulence compensation will be degraded greatly. Numerical experiments are carried out about branch-point number for the straight flat beam and the focused Gaussian beam propagating in the atmospheric turbulence by four-dimensional code. Mainly two categories of propagation events are explored. In one category the laser beam propagates in weak atmospheric turbulence but long propagating length. In the other the turbulence is stronger but propagating length is shorter. With different calculation parameters and transmitted conditions, the branch point number and its evolvement are different. The relationship between branch-point number and propagation conditions is also studied, and a statistical model about branch point number is built. The work could provide a reference for further study of laser propagation through atmosphere and adaptive optics system.

In the He-Ne laser with an integrated cavity made of zerodur, the inner face performance of the gain tube is limited by the machining techniques, which tends to influence the beam propagation and transverse mode distribution. In order to improve the beam quality and select out the fundamental mode, an aperture is usually introduced in the cavity. In the process of laser design, the Fresnel-Kirchhoff diffraction integral equation is adopted to calculate the optical field distributions on each interface. The transit matrix is obtained based on self-reproducing principle and finite element method. Thus, optical field distribution on any interface and field loss of each transverse mode could be acquired by solving the eigenvalue and eigenvector of the transit matrix. For different-sized apertures in different positions, we could get different matrices and corresponding calculation results. By comparing these results, the optimal size and position of the aperture could be obtained. As a result, the feasibility of selecting fundamental mode in a zerodur He-Ne laser by a circular aperture has been verified theoretically.

The transmitting and receiving optical system for the scannerless laser radar are designed and simulated in ZEMAX. In the transmitting optical system, in order to increase the operating distance, a beam expander telescope which is used for reducing divergent angle of laser beam is chosen. To make fully use of light, a micro lens array is used as a beam splitter. In the receiving optical system, in order to improve the filling factor of APD array, a micro lens array used to replace the previous usual lens is studied. The simulation shows that the density of the light spot after split was uniform, and demonstrates that the designed array illumination is feasible. In the part of receiving optical system, each beamspot through micro lens array can match perfectly with the APD unit cell, and the receiving efficiency is improved effectively.

This paper introduces the infrared optical system in the Tokamak fusion reaction device. In this optical system, the traditional optical structure can't meet the requirements, because the length of the infrared optical system in the Tokamak is very long. The design of optical system in the detection facility includes three parts:1.the combination of the concave aspheric mirror and flat mirror; 2.the Cassegrain system; 3.the relay group lenses. This paper describes the decrease of the modulation transfer function (MTF) when the temperature changes and how to compensate the decrease of the MTF in order to maintain the image quality in a high level. As a result, the image quality of this optical system can reach the requirements when the temperature changes.

The characteristics of the LDA operating in the steady state are analyzed. The carrier density, oscillating frequency, photon density compared to those in free-running state operating in the in-phase mode are analyzed. In this paper, linewidth narrowing and wavelength stabilization of a high-power laser diode array are obtained by using an external cavity consisting of Volume Bragg Grating (VBG) with the reflectivity of 15 %. At the driven current up to 40 A, an output power of 28 W is obtained with the linewidth down to 0.3 nm, which corresponds to the efficiency of 93.3% compared to the output power in free-running LDA. The intensity of the external-cavity LDA is improved by a factor of approximately 3.3, and the wavelength is stabilized at 808nm determined by the VBG. This kind of laser diode array has potential applications in pumping solid-state lasers, medical treatment and gas sensing.

According to technical requirements,an apochromatic telescopic optical system which is characterized by the focal length 1.5m~2m,with the visible region spectrum band is needed.The successful design consists in using normal glasses based on PWC method to get a completely secondary-spectrum-removed and cramped construction telescopic optical system in this paper.Firstly, by the aberration theory and ZEMAX optical design software,a catadioptric achromatic optical system composed of a reflecting mirror and a couple of air-spaced negative doublets are designed.The initial configuration of optical system is calculated by PWC method and the proper couple of air-spaced negative doublets are chosen by the theory of achromatic.By comparing with various optical systems with different couple of air-spaced negative doublets, it is found that the combination of the heavy crown glass ZK7 and heavy flint glass ZF3 is effective to correct chromatic aberration and its secondary spectrum value is minimality.It can conclude that fact with the abbe number of ZK7 is twice than ZF3 make the good result and give guiding to the design of the same type of optical system. Secondary,according to the theory of secondary spectrum,the secondary spectrum value to be corrected is analyzed and the compensation can be changed by adjust the magnification power.The comparison is presented and the final telescopic optical system with cramped construction is achieved, and the goal of apochromatism and other aberration is reached.

In this paper, a new data hiding method - writing on wet paper using multi-pixel differencing is presented in order to provide large embedding capacity and improve further steganographic embedding efficiency for the stego-image. It takes into consideration four pixels of a block, and the differences between the lowest gray-value pixel and its surrounding pixels are used to embed the secret data. The receivers can extract secret bits from carrier images only by some matrix multiplications no matter how we embed the secret message. Thus, the invisibility of this steganographic method is achieved in process of secret information transmission. The experimental results show that our scheme has a larger embedding capacity and better robust performance against the methods of active attacks such as noise addition.

A novel moderate-resolution imaging spectrometer spreading from visible wavelength to near infrared wavelength range with a spectral resolution of 10 nm, which combines curved prisms with the Offner configuration, is introduced. Compared to conventional imaging spectrometers based on dispersive prism or diffractive grating, this design possesses characteristics of small size, compact structure, low mass as well as little spectral line curve (smile) and spectral band curve (keystone or frown). Besides, the usage of compound curved prisms with two or more different materials can greatly reduce the nonlinearity inevitably brought by prismatic dispersion. The utilization ratio of light radiation is much higher than imaging spectrometer of the same type based on combination of diffractive grating and concentric optics. In this paper, the Seidel aberration theory of curved prism and the optical principles of Offner configuration are illuminated firstly. Then the optical design layout of the spectrometer is presented, and the performance evaluation of this design, including spot diagram and MTF, is analyzed. To step further, several types of telescope matching this system are provided. This work provides an innovational perspective upon optical system design of airborne spectral imagers; therefore, it can offer theoretic guide for imaging spectrometer of the same kind.

This paper presents the impact of the light source expanded width on the detection sensitivity in an optical readout uncooled infrared system, which consists of a focal-plane array (FPA) containing bi-material cantilever pixels and reflectors. The relationship between the light source expanded width and the detection sensitivity is discussed based on four different curvatures of reflectors(R=8mm,11mm,25mm,∞). The analysis indicates that the detection sensitivity decreases with the light source expanded width's increment. For the flat reflectors , the detection sensitivity decreases to 90% when the light source expanded width is about 0.64mm. Compared with the flat ones, when the curvatures of reflectors are smaller, the requirement of light source expanded width becomes lower for the sensitivity. The experiment intuitively shows that the image quality by using the light source with 0.05mm size is better than the one with 1mm size, which confirms the first conclusion.

Based on the wave theory of aberrations, the Point Spread Functions (PSFs) of optical synthetic aperture imaging system disturbed by some aberrations, such as Piston error, Tilt error, spherical aberration, astigmatism, were analyzed. Additionally, the analytical expressions of the central value of the PSF (CVPSF) on Piston error and Tilt error were deduced, and were simulated by MATLAB. The results show that when one sub-aperture of an N identical sub-apertures synthetic array is disturbed by Piston error, the PSF fluctuates periodically. Furthermore, the PSF decreased by Piston error, spherical aberration or astigmatism can be significantly compensated by defocus. And CVPSF is improved from 0.60 to 0.93 for the spherical aberration after it is compensated by defocus.

This paper presents a new-type application that interlinks the none-digital world with digital world based on the photo sensors. Nowadays, Tangible User Interfaces (TUIs) have emerged as a novel interface pattern. It combines the users' knowledge of physical interaction and digital information together. Meanwhile, the interactive tabletops with optical sensors show great potential in the field of entertainment, display and education. The system fuses the tangible user interface and tabletop interaction into an organic whole. With low consumption and high brightness, it achieves the identification of different physical entities.

Laser indued breakdown spectroscopy(LIBS) system was used for analysis of heavy metals (Cr, Pb, Cu, Ni, Cd, Zn) in soil. And neuro-genetic method was applied to optimize the system parameters in order to maximize the signal-background ratio of all heavy metals simultaneously. LIBS system equipped with an Andor Echelle spectrometer, coupled to an ICCD detector. A Q-switched Nd:YAG laser was used to induced plazma. Delay time, integration time, scan times of laser pluse, frequency of laser were optimized. The optimized parameters were obtained: 1μs delay time, 4.5μs integration time, 48 scan times, and 11Hz frequency of laser.

Adaptive optics is one of the most effective techniques for high resolution imaging. The adaptive optics system without wave front sensor is required in many applications. In a wave front sensorless adaptive optics system, the wave front aberration is derived from the image quality metric function through given algorithm. In this paper we study the optimization model based wave front sensorless adaptive optics correction approach and its application in space remote sensing imaging. The application efficiency of the algorithm depends on related parameters in the algorithm such as the spatial frequency range of image and the biases. In this paper we present a new selection method of the biases, give a reference spatial frequency range and promote the algorithm to improve the correction accuracy. At last we present the performance of model-based wave front sensorless adaptive optics scheme for space remote imaging through simulation.

The study of the transfer function characteristic of long-base laser strainmeters is the base to explain the interferometer output data. The long-base laser strainmeter comprises the long-base optical interferometer and signal demodulation system, by measuring the change in displacement between the fixed points to determine the actual strain. According to the principle of the strainmeter and the working process of the signal demodulation system, we completed the theoretical modeling of the optical interferometer and the demodulation system, and determined its amplitude-frequency and phase-frequency characteristic. And we obtained the transfer function characteristic curve, providing a basis for the analysis of system output data and the optimization of the laser strainmeter design.

The measurement theory of optical fiber F-P temperature sensor is analyzed according to difficult problem that temperature is real-time measured in the study of thermal interaction between laser and bio-tissue. The model of temperature and strain is established. The work point stabilization method of optical fiber F-P sensor is studied. The optimal model of low fineness optical fiber F-P sensing system is established based on the technique of dual optical wavelength stabilization. The experimental device of real-time measurement temperature is build. The experimental results show that the sensor has higher measurement precision and small bulk. And the hurt is little for bio-tissue. It can be used to the real-time temperature measurement of bio-tissue efficiency. When the sensor is used to the continuum temperature measurement, the maximum absoluteness error is 0.63°C and the maximum relatively error is 1.4%. When the sensor worked half hour, the maximum cumulate error is 1.3%.

Wave-front coded system is proposed to improve the depth of field and is proven effective. Although there are researches interested in modulation transfer function (MTF), the sampling interval is not specified. We start from the basic model of wave-front coded system and investigate the sampling interval of the optical transfer function (OTF). Then, the simulation of imaging process is performed in computer and the result is illustrated.

Based on Fourier infrared spectrometer, the mid-infrared normal spectral emissivity measurement device with high accuracy was developed in Spectrophotometry Laboratory, National Institute of Metrology, China. It was composed of Fourier infrared spectrometer, black body, heater and the auxiliary optical components. It can work at 100 to 450°C with heating function and can work at up to 1100°C only for self-heating materials or systems. The measurement wavelength range covers the whole middle infrared light 2.5-25um, and the measurement uncertainty is better than 2%(k=2) at any measurement temperature point for self-heating materials or systems.

A Dual-field-of-view (DFOV) lenses has been developed, which is for MWIR band with high ratio used by 3rd generation thermal imager. The lenses change the field of view by flipping in or out a group of optical elements. The lenses' ratio of DFOV is six, the focal length of narrow field is 240 millimeter, F-number is 4. As a result of smaller pixel size, the lenses have to provide high image quality. It is folded to get smaller volume. Because the detector contains cold stop and the lenses contains moveable group, narcissus is examined and minimized. Reference source is set at a suitable position to correct non-uniform of detector. Field stop is set at the first image surface to minimize stray light. The lenses improve thermal imager spatial resolution by micro-scanning which is realized by jiggling motion of the last element at two directions.

To improve the sparse-optical-synthetic-aperture system's image quality, the impacts of sub-apertures' aberrations and piston errors should be considered comprehensively for broadband target wave. Based on basic optic principles, the system's Strehl Ratio (SR) for broadband target wave was deduced thoroughly, which led to the analysis about variances of the system's SR metric under different sub-apertures' aberrations and piston errors. The results showed that for broadband target wave, the system's image quality is jointly influenced by sub-apertures' aberrations and the piston error, and the correction of piston errors is meaningful only when the sub-apertures' self aberrations are controlled with certain limit.

A photoelectric autocollimator of large measuring range for detecting position accuracy of NC rotary table is designed. The autocollimator has a measurement range of ±30'. The measurement accuracy and the resolution of the autocollimator are 2" and 0.32" respectively. The autocollimator applies an area CCD camera as its detector, which can realize two-axis measuring at the same time and automatically detect the position of the rotary table. The important components of the autocollimator are designed such as objective lens, ocular lens, cross reticule, beam splitter prism. A LED light is used in the autocollimator for its high brightness. Using the ZEMAX optical design program, the light path of the system is analyzed and optimized to ensure the spherical aberration within -0.05mm~+0.05mm and the sine aberration of 0.0003mm. The MTF value of field of view is more than 0.5 at the half Nyquist frequency. The MTF is higher than 0.3 within 0.7 FOV at the Nyquist frequency. RMS radiuses are less than Airy disk. The mechanical structure of the autocollimator is designed. And two adjusting devices to regulate the position of the reticule and the objective lens are designed to ensure the reticule at the right position and to get an excellent imaging performance in CCD. The performance of the debugging sample machine has been tested, The error of indication of the autocollimator is contrasted and the result is consistent with the specification above.

With the aim to measure the radius of curvature deviation and the surface form deviation of optical elements online in the workshop, based on laser testing technique, two solutions of miniaturization without precision guider sphericity interferometer systems are described, and the principle of systems are analyzed. Compared with the traditional sphericity interferometer, the systems designed are particularly suitable for testing mirror noncontact online in workshop, advantaged in compact structure, no precision guider, high efficiency and low costs. The interferometer systems use the different radius of curvature of existing spherical test plates in the production workshop to produce reference wavefront. The systems can not only get the astigmatism and local deviation of lens, but also can reflect the radius of curvature deviation, which provides rapid and nondestructive noncontact online testing.

This paper developed an intelligent optical fiber refractive index profile measurement system. This system is based on the principle of the refracted near-field measurement. The whole system is the use of a unique high-resolution non-contact capacitive displacement sensor to monitor the scanning position of the fiber measured. At the same time we used a shading screen which was embedded into the sample pool. Using this method, we can totally save space. Finally, we used a high curvature condenser to collection of reflected light which we used a photo detector to collect. The collected signal was brought into the computer to calculate the optical fiber refractive index. The whole system is totally enclosed operating instrument with an easy-to-use software interface for performing measurements of both multi mode and single mode optical fiber, which can easy pick up the signal automatically and processing in computer. Measurement accuracy can reach 10^-4. It is fit for measuring the refractive index of single-mode fibers and multi-mode fibers.

A high-resolution extreme ultraviolet (EUV) spectrometer is developed to diagnose the magnetically confined plasmas in the spectral region of 5-50 nm. The spectrometer consists a holographic aberration-corrected concave grating, an entrance slit, an x-ray shutter and a deep-cooled back-illuminated CCD camera. This paper presents the spectrometer structure, the spectral resolution simulation. The spectrometer is tested by a Penning discharge light source which is a convenient wavelength calibration source working at EUV spectral range. This light source emits a number of standard spectral lines with different combinations of discharge gas and cathode material, which will provide different standard spectral lines for wavelength calibration and spectral resolution evaluation. Results show that the spectral resolution is about 0.015 nm at 20 nm which agrees with the design goal.

Bandwidth is an important specification for monochromator and spectrograph. It varies with different slit widths and wavelengths. In actual spectral measurement, it is usually need to know the bandwidth. In the case of a Czerny-Turner double monochromator, we measured its bandwidth in finite different wavelengths as well as slit widths. Bandwidth can be represented as a function of wavelength and slit width. After the experiment, we get bandwidth in some discrete wavelengths and slit widths, bandwidth in other wavelength and slit width can be computed through mathematical process of the data that already acquired.

Based on the definition of spectral emissivity, an experimental apparatus for normal spectral emissivity measurement at different temperatures has been developed. The sample and blackbody are heated by the same heating system, which permits to measure spectral emissivity up to 1273K. The temperatures of the sample and blackbody are measured and controlled by an infrared radiation thermometer and PID controller. The signal detection is carried out by a silicon photo detector at 1.5 μm. The experimental results focus on the capability of the apparatus to perform emissivity measurements as a function of temperature at a fixed wavelength. Using this apparatus, the spectral emissivity of SUS304 is first measured at different temperatures. In order to validate the measurement capability of the apparatus for different sample, three kinds of steel samples which have different percentages of constituents were measured. The measurement uncertainty of the experimental apparatus is analyzed. The overall uncertainty of the apparatus estimated is about 5%.

This paper proposes a novel Micro-Opto-Electro-Mechanical-System (MOEMS) based beam steering method mainly designed for far operating distance applications. The proposed system incorporates a MOEMS analog mirror developed by Texas Instruments Inc. as core component and a beam expanding telescope. The analog mirror can change angle within a ±5° range of mechanical rotation in two axes. The expanding telescope could reduce beam dispersion caused by diffraction of the mirror's boundary. Expressions of steering equation, steering range and angular resolution are deduced. Steering trace and far field steering beam patterns are simulated. Analyses on main performance of the system are proposed.

Optic imaging system is information transmission system. The quality of imaging depends on the transmission characteristics of optical system completely. The bi-grating diffraction imaging is the formation of the image of an object with two gratings. First,gather object information and transform them into object beams by irradiatiion of incandescent lamp. Then the first grating disperses the muti-color object beams with object information and second combines the dispersed light beams to form the image.This paper describes the characteristics of information about object color and size transmission. The characteristic is studied by theoretical analysis. The relationship between the two gratings' spatial frequencies and diffraction orders that reflecting the information of object color and size transmission quality on certain condition is given. To recognize the transmission characteristics of bi-grating diffraction imaging deeply is very helpful for its application.

In this article, it presents a suit of single channel input virtual Dual-Phase Lock-in Amplifier (DPLIA) that is constructed by a personal computer sound card and the LabVIEW software. The virtual DPLIA is low cost and convenient to implement. The implemented DPLIA could enhance the noise tolerance capability and lower the LOD of the optical signal detection system. A primary benefit of this instrument is it only needs one input channel; two internal reference signals of the digital PLL are generated in the LabVIEW software. It is easy to control and operate, the data processing results can be saved directly to disks. This instrument will be applied in other weak signal detection systems.

High spectral resolution lidars (HSRLs) are increasingly being deployed on aircraft and called for on future space-based missions. The HSRL technique relies on spectral discrimination of the atmospheric backscatter signals to enable independent, unambiguous retrieval of aerosol extinction and backscatter. A compact, monolithic field-widened Michelson interferometer is being developed as the spectral discrimination filter for an HSRL system at NASA Langley Research Center. The interferometer consists of a cubic beam splitter, a solid glass arm, and an air arm. The spacer that connects the air arm mirror to the main part of the interferometer is designed to optimize thermal compensation such that the maximum interference can be tuned with great precision to the transmitted laser wavelength. In this paper, a comprehensive radiometric model for the field-widened Michelson interferometeric spectral filter is presented. The model incorporates the angular distribution and finite cross sectional area of the light source, reflectance of all surfaces, loss of absorption, and lack of parallelism between the air-arm and solid arm, etc. The model can be used to assess the performance of the interferometer and thus it is a useful tool to evaluate performance budgets and to set optical specifications for new designs of the same basic interferometer type.

We proposed a dual-channel imaging polarimetry system .It will be integrated in our coronagraph that was proposed for direct imaging of Jupiter-like planets, providing an extra high contrast for the extra-solar planet imaging. This system uses a Wollaston prism, which separates the unpolarized starlight and the polarized planet light. The two point images in perpendicular polarizations are imaged simultaneously. We describe the design of the imaging polarimetry system, and discuss the data reduction algorithm. In particular, the correction of distortion of the two channels is discussed in detail.

This article describes high beam quality and kilowatt-class diode laser system for direct materials processing, using optical design software ZEMAX® to simulate the diode laser optical path, including the beam shaping, collimation, coupling, focus, etc.. In the experiment, the diode laser stack of 808nm and the diode laser stack of 915nm were used for the wavelength coupling, which were built vertical stacks up to 16 bars. The threshold current of the stack is 6.4A, the operating current is 85A and the output power is 1280W. Through experiments, after collimating the diode laser beam with micro-lenses, the fast axis BPP of the stack is less than 60mm·mrad, and the slow-axis BPP of the stack is less than 75mm·mrad. After shaping the laser beam and improving the beam quality, the fast axis BPP of the stack is still 60mm·mrad, and the slow-axis BPP of the stack is less than 19mm·mrad. After wavelength coupling and focusing, ultimately the power of 2150W was obtained, focal spot size of 1.5mm * 1.2mm with focal length 300mm. The laser power density is 1.2×10⁵W/cm², and that can be used for metal remelting, alloying, cladding and welding. The total optical coupling conversion efficiency is 84%, and the total electrical - optical conversion efficiency is 50%.

Zernike polynomials are usually used to describe the wave-front of an optical system, but it is also used to stand for the surface of an optical system. Researching the algorithm in this paper is according to this property. When temperature of a lens increases from -60°C to 60°C, the surface of the lens will change simultaneously, which will influence the image quality and the sensitivity of the detector. In this paper this progress will be simulated by finite element software, abaqus. After that the data of the lens whose surfaces have deformed will be exported. Zernike polynomials are used to describe the changed surface, and zernike coefficients are calculated with matlab by using the method of least squares. All of the the zernike coefficients are imported to an optical design software, zemax, and then the aberrations coefficients can be got from the software. Finally, the solution of avoiding these problems caused by temperature changing can be obtained.

In the process of global climate change and weather forecast, the cloud is an important parameter. The complex change mechanics among different phases of cloud and the dramatical changes in its time and space dimension results that cloud is the variance that's the most difficult to describe among the metrology elements. In the future of cloud and radiation parameterization scheme, the introduction of detailed micro-physical processes is an essential development, therefore, it's very important to research the cloud parameters. This paper uses Micropulse Lidar (MPL) to discriminate cloud ice/water phase. MPL systems provide continuous, autonomous observation of nearly all significant atmospheric clouds and aerosols. Being compact in structure and with eye-safe transmitted radiation, the systems proved reliable in a number of experiments both at home and abroad. MPL primarily use depolarization ratio to classify cloud phase as ice or water, the transmitted lidar beam is nearly 100% linearly polarized. Depolarization of the return signal from the molecular atmosphere is about 0.35% due to narrow optical bandwidth of the receiver which blocks most of the highly polarized Stokes and anti-Stokes lines. It is well known that backscattering from ice crystals results in appreciable signal in a polarization plane perpendicular to the plane of the transmitted lidar beam. Depolarization from ice crystals depends on crystals shape and aspect ratio and is typically in the range of 30%-50%. In contrast, backscattering from spherical water droplets preserves the polarization of the incident light.