In order to solve the problem of large difference of gray level and the difficulty of common feature extraction for optical and SAR image registration, an improved multi-model contour feature image registration method is proposed which is based on k-mean clustering segmentation and mathematical morphology. The k-mean clustering algorithm is used to get two kinds of image segmentation region, and through the mathematical morphology processing, accurate extraction of two classes of closed contour image has been realized, which can reduce the influence of the SAR image speckle noise effectively. The matching strategy of the mean and variance of torque variable distance constraint mechanism along with consistency check is bring in which aims to obtain the best match result. Through the experiment, image registration precisions of three groups reach 0.3450, 0.2163 and 0.1810, respectively, which indicates that this method is feasible and can achieve sub-pixel registration accuracy.

Backscattering lidar is a powerful tool for atmospheric aerosol detection, but the blind and transition regions restrict its detecting range and precision in near distance. Side-scatter lidar based on charge coupled device (CCD) can detect aerosol continuously in near distance with great precision. The characteristics of interference light and background light in side-scatter lidar are analyzed, and the way to decrease them is found. The characteristics of atmospheric scattering light generated by laser are analyzed, and the scattering light superposition from the same distance is computed. Matlab software is applied to retrieve signals, and the comparison between the proposed method and the backscattering lidar signals is made. The result indicates that this retrival method is reliable and feasible.

Atmospheric correction of remote sensing image is the precondition of inversing water color parameters. An atmospheric correction method for lake Taihu based on 6S the radiative transfer model and the NIR water-leaving reflectance model is proposed. Two neural networks are built to model radiative transfer, and thereafter, estimate parameters such as aerosol optical thickness in 550 nm with the optimization of four near infrared bands (i.e, 754, 779, 865 and 885 nm) of medium-resolution imaging spectrometer (MERIS) data. Then, the parameters are extrapolated to visible wavelength to fetch the parameters in those visible bands. This model by MERIS Level 1p data on November 11th, 20th, 21th, 2007 and November 20th, 2008 and the in situ date-sets is validated. The result indicates that the radiative transfer optimized model has a high precision in inversing the water remote sensing reflectance with an average relative error from 20% to 40% in the 13 bands. Comparing with the atmospheric correction methods of 6S and Beam 4.9, it has the highest correction precision and strongest stability, and is applicable in lake Taihu.

Expression of the residual scintillation index of a received intensity from a rough target in atmospheric turbulence is derived by using the extended Huygens-Fresnel principle combined with the Rytov method. The formula is numerically evaluated in the cases of spherical wave and plane wave incidences, and the results agree with those obtained by the slip-step Fourier method, which proves the validity of the theory. The relationship between the residual scintillation index with the target size and the propagation distance is analyzed, which proves that the residual scintillation index is the scintillation index on the target plane averaged by the target aperture.

A high-speed single-photon detection technique based on gated InGaAs/InP avalanche photodiode (APD) is proposed. The 1.5 GHz harmonics ultrashort pulse is applied to an InGaAs/InP APD, and the photo-excited avalanche signal is buried in the harmonics noise due to the capacitive response of APD. By utilizing a 700 MHz low-pass filter, we achieve 50.6 dB noise suppression and extract the avalanche signal efficiently. With the InGaAs/InP APD operated under -30 ℃ by thermal electrical cooler, and driven by 1.5 GHz harmonics ultarshort pulse gating, a detection efficiency of 35% at 1550 nm with the dark count probability of 6.4×10-5 per gate is obtained, and the afterpulse probability is 6.0×10-5 per gate after 2.7 ns at the detection efficiency of 15%.

To improve the accuracy of small photoelectric encoders without increasing the size, the reason how interpolation errors are generated by the calculation method is analyzed. A new photoelectric encoder fine signals interpolation method based on coordinate rotation digital computer (CORDIC) algorithm is proposed, and it can make use of simple shifting and addition operations to directly interpolate acquired quadrature fine signals and resolve the phases, which can get rid of interpolation errors caused by looking up in the interpolation table. The algorithm is analyzed and improved finally, and the calculation speed is proved while maintaining appropriate accuracy. Moire fringe signals from a 16-bit small photoelectric encoder are interpolated into 256 parts with the suggested algorithm, and the root mean square error is decreased by a half compared to the calculation method. Experimental result shows that the new interpolation method can be directly applied to high-accuracy interpolation of moire fringe signals. It may play an important role in the further research and development of small and high-accuracy photoelectric encoders.

Research of the tunable two-dimensional hexagonal phase array grating based on periodically poled Mg-doped LiNbO3 (PPMgLN) crystal and its Talbot effect of light diffracton imaging is presented. Theoretical simulation is executed to study the intensity distribution of near-field optical diffraction under various phase differences and fractional Talbot distances. Average intensity of the sample area in diffraction field is simultaneously calculated with phase difference and fractional Talbot distance, so the position of the maximum intensity of the sampling area is located as the phase difference is constant or changing. On the basis of theoretical research, the tunable hexagonal phase array grating is designed and fabricated based on periodically poled Mg-doped LiNbO3 crystal. The Talbot diffraction imaging is successfully obtained, and the experimental results agree with the theoretical results well.

A microwave photon upconversion scheme based on a vertical cavity surface emitting laser (VCSEL) without local oscillator is proposed. The relatively low pseudo-random baseband signal is injected into the VCSEL, and the higher harmonics of the injected signal is used to lock the VCSEL. The injection-locked laser wavelength beats coherently with the original optical signal in the cavity which generates the upconverting amplitude modulated microwave signal. In the experiment, 2.5 Gb/s nonreturn-to-zero code intensity modulated signal is used to inject-lock the VCSEL, which achieves a carrier frequency of 14.3 GHz microwave photon upconversion without local oscillator, and the carrier phase noise is -81 dBc/Hz at 10 kHz frequency deviation. Furthermore, modulation of 7.5~23 GHz carrier frequency can be achieved by adjusting the wavelength and power of injection signal, and the feasibility of the scheme is verified. The bit error rate performance of the system is analyzed, and system consideration is 1.4 dB. The result shows that the upconversion signal can be achieved by only using the inexpensive VCSEL without microwave local oscillator, which provides a low cost solution idea for the wireless-optical hybrid access network photon microwave signal generation technique.

The coupled-mode equations based on data-pump degenerate four-wave mixing (FWM) are presented for multi-wavelength regeneration. The equalization method using quasi-phase-matching is put forward for time-interleaved wavelength channel regeneration. Starting from optimizing the phase-mismatch factors of degenerate FWM, the equalization and regeneration of fixed or arbitrary four wavelengths are realized by the optimization of wavelength distribution or the fiber parameters, respectively. The calculations show that the variations of output peak power, extinction ratio (ER) and Q factor for the equalized channels are less than 0.25 dB, 0.42 dB and 1.5, respectively.

The influence of nanoimprint technology on the epitaxial materials is analyzed with the use of photoluminescence and X-ray diffraction. 1.55 μm distributed feedback (DFB) laser diodes for optical fiber communication are fabricated using nanoimprint technology, and then accelerating life test is applied to these devices. Results show that soft stamp nanoimprint will not lead to a serious degradation of the epitaxial materials. The lifetimes of the lasers fabricated by nanoimprint and exposure method are on the same order of magnitude, indicating that nanoimprint technology is safe and reliable to the fabrication of lasers.

A novel fiber model with isotropic crystal cladding, uniaxial anisotropic crystal fiber core that optical axis is parallel to the x-axis is proposed. The field intensity distribution is approximately obtained by waveguide equation. Using the transmission matrix method and numerical simulation method, the dispersion curves that the propagation constants β of o ray and e ray change with normalized frequency V are analyzed. By deeply analyzing the influence made by cores of optical fibers on dispersion curves, it is shown that the radii of optical fiber cores don′t exert influence on cutoff frequency. Based on the above results, the curves that the propagation constants β of o ray and e ray change with optical fiber core are achieved respectively. By analyzing the influence of the dielectric constants on dispersion curves, it is indicated that the polarized direction of light in the fiber can be changed by the ratio of x directional dielectric constant and y directional dielectric constant in the certain range of normalized frequency propagating in the fiber. This work provides a theoretical foundation for designing the polarization fiber.

A surface plasmon resonance (SPR) sensor based on side-polished fiber is fabricated by coating a thin gold film on the polished zone. The characteristics of the sensor for ambient refractive index and temperature are tested. The results show that the resonance dip shifts to longer wavelength as the ambient refractive index is increased and shifts to shorter wavelength as the temperature is increased. The average sensitivity of resonance wavelength to variation in refractive index is 4.1×103 nm/RIU (RIU is the unit of refractive index). Moreover, a linear sensitivity of resonance wavelength to variation in temperature reaches 0.36 nm/℃. The fiber optical SPR sensor, possessing stronger resistance to temperature drift and higher refractive index sensitivity, can play an important role in biochemical sensing.

The orientation change of nematic liquid crystal (NLC) can be used in biosensor. The sensing characteristics of side-polished fiber (SPF) for measurement of NLC orientation are investigated. The relationship between the theoretical formula of liquid crystal refractive index and the optical transmission power in SPF is derived by empirical approach. The mechanical rotating method is designed to change the orientation of NLC on the polished surface. Experimental results show that the orientation variation of liquid crystal can indeed be used to monitor the output optical power transmitted through the SPF. With mechanical rotation method, when the rotation angle increases from 0° to 90°, the output optical power increases by 28.10 dB. With in the angle range from 0° to 30°, the response is almost linear. The average response slope is about 0.359 dB/(°), which indicates relatively high sensitivity. Experiments indicate that SPF can be used to measure the orientation variation of NLC, and the variation range is also obtained. The work provides a reference for a new fiber optical biosensor based on the SPF and NLC.

In order to meet the concentrative requirements of concentration photovoltaics system (CPVs) and resolve the traditional point focus concentrator′s problems, including non-uniform irradiance, large aspect ratio and low concentration, a novel concentrator with small aspect ratio, uniform irradiance and high concentration is presented in this paper based on the precondition that no additional secondary optical element is increased. According to the theories of Kohler illuminating, constant optical path length, and Snell′s law in geometric optics, we obtain the profiles of concentrator′s surface through numerical solution of the constant optical path length equations. Using the optical software TracePro, we trace and simulate the CPVs. The results show that the maximum irradiance value of focal spots on the surface of solar cell is only 2300 times of the sun for the 725 concentration ratio, which is about 1/10 of the case of point focus concentrator. The aspect ratio of system is 0.3, and the acceptant angle is 0.72°. The design realizes the objectives of compact structure and high concentrative performances, which provides an effective way for realizing the high concentration CPVs′ miniaturization and simplification.

A method of pedestal component elimination is proposed using line CCD for spatial-filter velocimetry (SFV) signal, which is based on spatial filtering effect of line CCD. By using difference demodulation arithmetic, pedestal and direct current (DC) components are eliminated, both amplitude and signal noise ratio are improved at the same time. Characteristics of equivalent difference spatial filter are analyzed with the research of power spectral density function of spatial filter difference demodulation. The feasibility of pedestal component elimination using difference demodulation arithmetic is validated with experiments. The result shows that difference demodulation arithmetic can eliminate pedestal and DC components, and amplitude of signal component is doubled, which will benefit the pick-up of useful signal component.

An iterative matching method based on choosing optimal mask and representing deformation by the quadric function is proposed to solve the matching problem of 2C level lunar images by Chang′E 1 (CE1) lunar probe satellite. The simulation results show that it has high precision and stability which self adapts well to the relief terrain′s imaging deformation. A precise matching is applied to the normal view, forward view and backward view of the CE1 image by combining the proposed method and the standard correlation method. Affine model approximating the imaging of line scanner camera is analyzed and applied to the same orbit′s three-view reconstruction. The adjacent orbit′s lunar terrain registration is realized by RANSAC estimation of three-dimensional (3D) coordinate transformation parameters led by matching feature points of adjacent normal views. The experiment results indicate that the shape and terrain of lunar surface can be better understood from the reconstructed results.

Spectral domain optical coherence tomography (SDOCT) is a new biological imaging technique. The traditional reconstruction method in SDOCT is based on Fourier transform. One disadvantage of this method is that the axial resolution of the system decreases with the increase of the imaging depth. A new reconstruction method is proposed which has the capability of maintaining the axial resolution over the all imaging depth. To prove the accuracy of this method, the cross-sectional images of the mirror and skin are obtained. The results demonstrate the effectiveness of the method. Compared with the methods reported, the new method has the advantage of not increasing the complexity of the system while having an almost constant axial resolution over the imaging depth.

An in situ aberration measurement method based on a two-dimensional (2D) phase-shift rings target is proposed for quality evaluation of the lithographic projection lenses. A linear model between aerial-image intensity distribution and wavefront aberrations is built by principal component analysis (PCA) and multivariate linear regression analyses. Compared with the binary target in the AMAI-PCA method, the aerial images of the phase-shift rings contain more information which owns the ability of eliminating crosstalk between different kinds of aberrations, therefore, the accuracies of aberration measurement are improved. Impacts of aerial-image defocus error on the extractions of aberrations are analyzed. A measurement method for defocus error is also proposed. Simulations with the lithographic simulator Dr.LiTHO show that the proposed method can detect 12 terms of Zernike coefficients (Z5~Z16) with maximum error of 1×10-3λ. Simultaneously, the speed of aberration measurement is doubled because less aerial images need to be captured for the merit of applying the new 2D target.

In order to measure the wide-frequency-range image motion caused by spacecraft attitude instability or residual vibration of the vibration isolation devices, image motion measurement method using images taken from time delayed integration (TDI) sensors, overlapped area is proposed. Offset coefficient is defined to measure the mismatch between image motion velocity and integration time. The relationship between mismatch and image quality using modulation transfer function (MTF) as image quality evaluation index is analyzed. The image motion measuring accuracy range is determined. By taking full advantage of features of the images taken from TDI sensors, overlapped area that have the same content but are taken at the different time, the theory of image motion measurement method based on images taken from TDI sensors, overlapped area is elaborated. Experimental results show that the measurement precision can reach 0.2377 pixel, and the measurement bandwidth can reach 228 Hz, proving that this method can effectively achieve wide-frequency-range, high-precision measurement of image motion.

Frequency sweeping interferometer is very sensitive to drift of optical path difference. Drift error is multiplied by an amplification factor to thousands of times, seriously affecting the measurement results, so it is necessary to remove or reduce drift error. For low-frequency vibration or slow drift of objective mirror under laboratory environment, the amplified drift errors of two consecutive forward and reverse scanning measurements are approximately equal in quantity but opposite in sign. According to these characteristics, a drift error compensation method by consecutive forward and reverse optical frequency scanning is proposed. Then, validation experiment is established to prove the feasibility of this method for vibration of objective mirror with frequency of 4.7 Hz and amplitude of 1 μm. The experimental results show that the standard deviation of 40 measurements decreases from 51.9 μm to 8 μm with distances up to 1543.3 mm, after applying this compensation method.

Microstructure surface topography is a key aspect of micro-nano measuring research for it has an obvious influence on the performance and quality of micro-nano devices. White light interferometry is a common method of testing surface profiling. A color CCD camera, rather than a black-and-white CCD camera, is utilized to acquire white light interference images, which contain information of RGB channels. Based on acquired color interference images, wavelet transform method is employed to calculate phase value of corresponding channel in each scanning position. Then zero-optical-path-difference positions are accurately determined via a constructed evaluation function and least square method. Surface topography is eventually obtained via linear relationship between the relative height and the zero-optical-path-difference position. The proposed method is verified by simulation and experiment of measuring standard step provided by VLSI Standards Incorporated.

An accurate measurement method of the polarized light′s phase retardation based on the crystal wedge is introduced, and is applied to measure the phase retardation′s temperature dependence of the zero- and multiple-order quartz wave plates. The measured results are insensitive to the power fluctuation of the light source, and the accuracy of the phase measurement can reach 0.05°. Compared to the traditional phase measurement, there is no adjustment of any optical components during the crystal wedge′s experiments, the on-line phase detection can be realized. This method can be used at the phase retardation measurement of any optical components, or at the various optical wavelengths.

With the use of fundamental wave of high power laser diode end-pumped Nd:YAG and the intra-cavity second-harmonic generation (SHG) effect and sum-frequency generation (SFG) effect of nonlinear optical crystal, a multi-wavelength yellow laser with simultaneous multi-second-harmonic outputs is proposed. By using 1112.1, 1115.9, 1122.7 nm outputs of Nd:YAG as fundamental waves, and selecting LBO and BIBO for nonlinear frequency conversion, three SHG lights and three SFG lights are obtained at the same time. The simultaneous stimulated transition of fundamental frequency lights and the phase matching nonlinear frequency conversion are analyzed theoretically. Experimental results and theoretical analysis show that when fundamental waves′ performances are relatively close to each other, reasonably choosing nonlinear crystals with good performance for frequency doubling and sum frequency of wavelengths at the same time is a practical method to realize all-solid-state multi-wavelength laser. Reasonably designing laser resonator can improve the stability of the laser.

For the number of inversion is decided by the effective pumping power provided by xenon flashlamp, the xenon discharge circuit and flashlamp radiation numerical model are built. With the use of the numerical method and the model above, the xenon flashlamp characters under different circuit parameters are calculated and compared to the experimental results. Two more practical concepts effective radiation efficiency and effective spectral efficiency are defined, to select optimal pumping energy and power entering xenon lamp. The results show that simulated annealing algorithm can be used to choose best capacitor and inductance rapidly , when the coefficients of xenon lamp and operating voltage remain constant. And the optimal power entering the lamp is also picked in this way. This method not only avoids the lowering of valuable energy proportion in the pumping area due to the violet-shift in spectrum, but also guarantees the life of the xenon lamp.

High power excimer laser system has its outstanding features such as short wavelength, broad bandwidth, et al. On the basis of adequate study of numbers of beam smoothing techniques in large scale laser facilities, the echelon free induced spatial incoherence (EFISI) technique is selected to accomplish the beam uniform irradiation in the angular multiplexed high power excimer laser system. In this way, measurements on dynamic uniformity of the seed beam after three paths amplification of pre-amplifier1 and double paths amplification of pre-amplifier2 with the use of partial coherence scattering seed and strict optical image relaying. Experimental results indicate that the uniformity of scattering seed is relatively kept owing to beam smoothing by EFISI technique. Typically, the nonuniformity of the beam after pre-amplifier1 amplification is 2.04%, and after pre-amplifier2 amplification is 1.96%. Meanwhile, the results mentioned above show that the technique adapts to the high power XeCl excimer laser systems.

A lot of stray light spreads in the near field of chemical oxygen-iodine laser, which has serious effects on beam propagation and beam quality control. Measurement methods for different types of stray light are brought out by analyzing and simulating generation mechanisms, types and propagation rules of the stray light. Efficiency for 30 m free propagation is measured by two energy meters. Angular power spectral curve in the channel and scattering energy reflected by the mirror are got by measurement diaphragms. Experimental results show that the energy loss after 30 m free propagation is 5.2%, angular power spectrum increases with propagation distance and deterioration of beam quality increasing. The heat burthens on all diaphragms in the tunnel can be calculated with angular power spectral curve, which lays a good foundation of heat control technology for high energy laser.

In order to consider factors such as system aberrations into account in the nonlinear propagation simulation of high power laser, a ray-tracing method for nonlinear media is presented, and hybrid modeling for linear and nonlinear media is realized through programming. Three-lens focusing system with KDP crystal as the nonlinear media is taken as an example, and simulation analysis of the influence of nonlinear effect on beam quality is conducted with different laser power densities. The simulation results show that when the laser power density reaches 1.62×1010 W/cm2, the laser beam quality is degenerated evidently by nonlinear effect. Based on the simulation results, an optimization method, which takes the optical component intervals as compensation without changing the position of focal plane, is presented. The optimization results show that the focal spot size decreases by 2.8 μm, and the encircled energy under standardized dimension increases by 16.2%, thus the beam quality at focal plane is significantly improved.

In the experiment of laser based on semiconductor optical amplifier (SOA), when the drive current of the SOA is up to 220 mA, by adjusting the polarization controller (PC), dark pulse is observed. The pulse durations are 74 ns and 20 ns with frequency repetition rates of 9 MHz (fundamental frequency) and 33.4 MHz (double frequency), respectively. By changing the position of the SOA in the nonlinear amplifying loop mirror (NALM), dark pulse width change accordingly.

In order to realize three-dimensional (3D) reconstruction for canopy and guide the operations of intelligent pruning, flower thinning and picking, a multi-image registration algorithm of apple tree at different growth stages is restigated. The robot vision system includes a color camera system and a photo mixing detector (PMD) camera. Image features at different growth stages are described by image similarity and reliable pixels. According to these image features. The optical calibration based on the distance information can be used from the flowering to the mature stage, while from the dormancy to the germination stage, the multi-image registration algorism should be used. Ninety groups of pictures, including the stages of mature, dormancy and flowering are used to verification the viewpoint. The experimental result shows that, the matching rate reaches 100% at mature stage and flowering stage, while 86.11% at dormancy stage.

In the light of underwater binocular image matching cannot satisfy the epipolar constraint of air, and the mismatching rate of underwater image processed by the scale invariant feature transform (SIFT) algorithm is high, we put forward an underwater feature matching algorithm based on curve constraint. Binocular camera should be calibrated, and some relevant parameters are obtained, as well as the reference image and the image to be matched; the SIFT feature matching algorithm can help to match two images, at the same time, the feature points can be extracted from the reference image to deduce the corresponding curve on the image to be matched. The curve is used as a constraint to determine whether the corresponding feature is on it, thus mismatching points will be excluded to achieve a higher accuracy. The test results show that this algorithm is superior to SIFT algorithm and can help to exclude mismatching points effectively. The matching accuracy can increase by about 12%. The problem of SIFT algorithm′s high rate of mismatching for underwater binocular stereo matching is solved.

As the helical axis of chiral nematic liquid is the optic axis, its spatial orientation affects the characteristics of the light propagation in liquid crystal directly. This paper studies on the influence of splay and bend deformation of chiral nematic liquid crystal on helical optic axis rotation angle and response time of flexoelectric effect by combining theoretical analysis and numerical simulation. Assuming chiral nematic liquid crystal molecules have a uniform rotation helix axis both in static equilibrium state and dynamic state and ignoring the dielectric anisotropy, the free energy densities of the two different states are calculated. The equilibrium equation and torque balance equation of the helical axis rotation angle are derived by using the Euler-Lagrange equations. The influences of the two deformation differences on helix axis tilt angle and response characteristics are discussed by numerical calculation. The results show that the difference of the two deformations makes both the helical axis rotation angle and the characteristic response time change. The bigger the difference is, the faster the change will be. The effects above can not be ignored. The results obtained in this paper provide a basis for rapid electro-optics response.

We study non-distorted imaging depths of optical coherence tomography (OCT) system in different tooth tissues based on Monte Carlo modeling of tooth OCT imaging. Two-dimensional simulated OCT images of single tooth enamel, dentin and two-layer tooth tissues are obtained by simulating the incident Gaussian beam and light propagation in dental tissues. The simulated images exhibit qualitative agreement with the experimental ones. The average non-distorted imaging depths of three kinds of dental tissue structure are gained through the analysis of one-dimension OCT signals corresponding to the simulated OCT images. It is indicated that the non-distorted imaging depths of the OCT system in dental tissues are 150~2400 μm, the non-distorted imaging depth of the enamel is much greater than that of the dentin. The results have certain reference value for the judgment on effective tissue structure information in experimental OCT images.

The elliptical windows testing technology has become the biggest block of development. In order to resolve the problem, the present testing technology for the asphere is expressed briefly. For the elliptical windows characterized by large tilt and large eccentricity deep asphere, based on the compensation theory, an improved Offner null testing compensator system for elliptical windows test is designed. The testing system includes compensator lens, field lens and a spherical reference mirror. The principle of Offner′s refractive null lens testing system is that when parallel light from interferometer passes through the compensator lens and the field lens, correction wavefront is produced. After transmission through elliptical window and reflection of spherical reference mirror, light returns back according the original path and interferes with the reference light. The interference results display elliptical window shape deviation. The null lens testing system is implemented and the whole design results are demonstrated. For the tested elliptical window with fineness ratio of 1.0 and aperture of 110 mm, the root-mean-square (RMS) value of the final residual wavefront error is 0.0052λ. Design results provide a certain reference to pratical applications.

Reasonable optimal system design and parameter optimization are prerequisite to achieve the functions of holographic femtosecond laser processing system. Based on the analyses of the requirements of the optical parameters of the holographic processing system, this paper makes an intensive study of the two key parameters. The oblique way which is more energy efficiency to irradiate the spatial light modulator is used to calculate the limiting conditions of the follow-up optical path design. Using the spatial light modulator and 4-f system which contain two lenses according to the demands of optical transmission, the optimal optical parameter design by deriving from the optical theory is given, and furthermore, the aperture simulation of the optical system with Zemax software identifies the rationality of the scheme. Finally, a reasonable holographic processing system is set up, and seven focus microlens arrays and micro gear parallel processing are achieved, respectively. Studies show that this optical design program can efficiently achieve the process of holographic femtosecond laser processing.

Airborne ocean colour remote sensing requires wide angle and large relative-aperture hyperspectral imager. Based on the research objective of wide angle and large relative-aperture, an airborne hyperspectral imager optical system is designed using an off-axis Schwarzschild telescope and a modified Dyson spectral imaging system. The field of view of hyperspectral image is 40°, relative-aperture is 1/1.8, and working waveband is 0.35~1.05 μm. Based on the aberration theory, the principle of spherical aberration correcting is analyzed in modified Dyson spectral imaging system. Ray tracing, optimization and analysis are performed by Zemax software. Results show that the modulation transfer functions for all wavelengths are bigger than 0.82; both smile and keystone are less than 5% of the pixel size. It is convinient for spectral and radiation calibration. The designed optical system satisfies the requirements of specifications, and it is small and light, suitable for airborne remote sensing.

Homemade Nd3+ doped chalcogenide glass microspheres are fabricated using the method of melting floating glass powder at high temperature. It is reported that the fluorescence spectra of chalcogenide glass microsphere are modified by the cavity quantum electrodynamic enhancement effect. A 90.53-μm diameter chalcogenide glass microsphere is coupled with the silica fiber-taper that has a cross-sectional diameter of 1.02 μm. An 808-nm laser is used as a pumping source for the microsphere cavity and separate resonance peaks found in the microsphere fluorescence spectra. According to the Mie scattering theory, positions and mode ordinals of three resonance peaks for the fundamental TE mode are calculated. Based on the formula for calculating the cavity quantum electrodynamic enhancement factor, it is found that the enhancement factor η of our chalcogenide glass microsphere is 1122, which indicates that spontaneous fluorescence emission rate is enhanced by 1122 times. By simplifying the enhancement factor formula for the fundamental TE mode, it is found that the enhancement factor estimated is 1167, which indicates an error rate of 4%.

The impact of optical source on the accuracy in recovery monochromatic frequency absolute phase demodulation algorithm for optical fiber Fabry-Perot sensor is studied in this paper. The relationship between phase demodulation value changes and the output spectrum of optical source is discussed both in theoretical aspect and demodulation experiment. Results show that the demodulating error has a relationship with the light source optical power. When the temperature changes from low to high, the source spectrum′s redshift causes pressure demodulation value error. The demodulation results show a quadratic relationship with various central wavelength of optical source, which is consisted with the theoretical analysis. Within the pressure range of 140 kPa, the central wavelength fluctuation of light source should be lower than 1.79nm when 0.1% demodulation error is needed.

The analogue of electromagnetically induced transparency (EIT) is achieved in a planar terahertz resonator consisting of a square closed loop (SCL) and a split ring resonator (SRR). Finite difference time domain simulations are carried out to analyze the EIT-like effect and its potential applications as a refractive-index-based sensor. Results show that the EIT-like resonance exhibits high refractive-index sensitivity and a high figure of merit (FOM) of 4.06, higher than that for SCL (0.09) or SRR (2.48) resonators. The refractive index and dielectric loss of the substrate, which influence the sensing performance of the SCL/SRR resonator, are studied, too. A device of the SCL/SRR resonator is fabricated by using laser-induced and chemical non-electrolytic plating with copper on polyimide film. Test results conincide with simulations.

A new kind of surface plasmon resonance (SPR) sensor based on hollow-core fiber structure is proposed. The performance of the designed sensor is theoretically analyzed with a ray model theory. Sensors with different silver film thicknesses are fabricated. An online testing system is set up and the SPR spectra of liquids filled in the fiber core with different refractive indices are obtained with the sensors of different silver layer thicknesses. Sensitivity and detection accuracy of the sensors are investigated both theoretically and experimentally. The designed sensor is a kind of fiber SPR sensor with high sensitivity, which can detect the high refractive index liquid medium in real time. It can make up the deficiency of the conventional fiber SPR sensor in a certain range and open up a new application field for hollow-core fiber.

A kind of surface plasmonic grating optical absorber with gradually varying geometrical parameters is designed, and its absorption characteristics are analyzed in detail by the two-dimensional finite-difference time-domain (2D-FDTD) method. Results show that the reflectivity can be effectively reduced and the absorption capacity can be enhanced by adjusting the depths of the grooves, the widths of the grooves and the thicknesses of the walls. By increasing the widths of the grooves linearly and reducing the thicknesses of the walls linearly from centre to the both sides at the same time, better absorption effect can be achieved. The shape of the reflection spectrum is different for different spatial full width at half-maximum of the incident light. When the full width at half-maximum is narrow, the absorption ability is stronger for shorter wavelength light. When the full width at half-maximum is wide, the absorption ability is stronger for longer wavelength light. This light absorber is expected to be applied in all-optical chips.

The olivine on the lunar surface is a diagnostic product of the moon′s formation and geologic evolution. Its abundance distribution is a hot spot in lunar exploration. It is possible to inverse the global lunar olivine abundance using the obtained reflected spectra. In this paper, 51 groups spectral data of lunar soils produced by the lunar soil characterization consortium (LSCC) and its corresponding olivine abundance are used to establish four regression models. The remaining 6 groups data are used to validate the models. Based on the calculation of coefficients, combined with validating LSCC data, the standard deviation, correlation coefficient and scatter plots of different models are compared, and the best optimized formulation statistically with the relationship between spectrum and olivine abundance is chosen. By using the Clementine UV/VIS/NIR data and the model, the global lunar olivine abundances are inversed and mapped. By comparing with the measured olivine abundance of the Apollo sampled soils, it is proved that the result is reliable.

An analytical model of modulation transfer function (MTF) for time-delay-integration (TDI) CMOS image sensor with oversample-superposition in the scanning direction is proposed. Impacts of sample number in a line-time, superposition number, TDI stage and velocity mismatch ratio on scanning MTF are studied based on the along-track-rolling exposure readout principle. To verify the scanning MTF model, an imaging simulation system is established, which is based on analysis of geometric and energy transmission relationship from continuous scene to discrete image on the TDI-CMOS image sensor. Then knife-edge method is used to calculate the MTF curve. The simulation results show that scanning MTF increases with the increase of sample number, scanning MTF is negatively related to superposition number when sample number is fixed, and scanning MTF decreases with the increase of velocity mismatch ratio and number of TDI stages.

High spectral resolution solar radiometer for ground-based measurement of atmosphere CO2 absorption spectrum is suggested, including a brief introduction of instrument design, method of relative spectral radiance measuring, calibration of spectrum and instrument line shape (ILS). It is indicated that in the spectral band between 1560 nm and 1575 nm, the spectral resolution of instrument is 0.097 nm, and the relative intensity of stray light is about 0.5%. For instrument validating, CO2 absorption spectrum of experiments are compared with those of theoretic calculation by LBLRTN software. Comparison shows that the relative intensity, wavelength position and shape of those two absorption spectrums are accordant.

This paper develops a new recognition method utilizing the phase information to improve the performance of radar high resolution range profile (HRRP) target recognition system. The statistical properties of complex HRRPs are analyzed, and three common Gaussian models, which are adaptive Gaussian classifier (AGC) model, jointly Gaussian (JG) model and probabilistic principal component analysis (PPCA) model, are generalized to the complex domain to model complex HRRPs. It is demonstrated that the structures and parameter estimators of the three complex models are invariant to the initial phase. Furthermore, to enhance the recognition performance under low signal-to-noise ratio (SNR) conditions, a noise robust modification algorithm is introduced. Experimental results show that the proposed method can obtain higher average correct recognition rates. Also, the modified models can deal well with the noisy test samples.

Lidar system is a powerful equipment of remote sensing with high spatial and temporal resolution and accuracy, which is widely used in atmospheric detection in regional or global scales. Overlap factor is an important factor that affects atmosphere detection with lidar system at near range. The accurate calculation is helpful to obtain more accurate detecting results. The overlap factor calculation method based on the laser intensity distribution is simple and practical. The algorithm not only applies to any specific laser intensity distribution, but also to results simulation with different initial parameters setting. Overlap factors are calculated with this algorithm, and calculation results are compared with experimentally measured overlap factor derived from the lidar signal. Moreover, we analyzed the influences of the system parameters on overlap factor and the sensitivity of the overlap factor. The results provide a certain reference to system debugging, optimization configuration and error control of lidar.

In the remote sensing camera of a satellite, its scanning mirror always bring the different rates image motion, which will make distribution of each point′s image motion on time delayed integration (TDI) CCD non-uniform. The distribution changes with angles of mirror, and it makes compensation for image motion difficult and effect of photograph un-satisfactory. For analyzing this situation, model of camera′s image motion vector with a scanning mirror is built. By concreting parameters, values of image motion and drift angles of each point on CCD with different angles of mirror are gained. When central point of CCD′s image motion is chosen as the standard of compensation, after compensation, if image motion value around all parts of CCD is below 1/3 pixel, the compensation is effective. With different angles of mirror, this effect of compensation is different. By analysis, when the angle of mirror is within the scope of (-20°,-0.12°) and (0.17°,20°), photos′ effect would be dim. This effect is satisfactory when angles of mirror are within the scope of (20°,35°) (-35°,-20°) and (-0.12°,0.17°). When angle of mirror is 0, this effect is satisfactory, and control precision of mirror′s angle should be within the scope of (-0.12°,0.17°). All of this study above can offer some reference for design of image stabilization mechanism.

A photoacoustic spectroscopy system which can measure the photoacoustic amplitude spectrum and phase spectrum simultaneously is constructed. Based on the conventional gas-microphone system, the phase measurement function is added to the system. The hardware configuration of the system is also optimized. It can scan wavelengths continuously from ultraviolet (UV) to near-infrared (NIR) regions within the range of 350~1000 nm with the minimal step length of 0.1 nm and the modulation frequency range of 10~2000 Hz. Using the virtual instrument software LabVIEW, the computer in the system can control instruments, set the experimental parameters, acquire and process data automatically. The front panel of the LabVIEW program can monitor the experiment dynamically and obtain the real-time spectra of both photoacoustic amplitude and photoacoustic phase. The system is evaluated with Ho2O3, and the normalized photoacoustic amplitude spectrum is consistent with the photoacoustic spectra reported by the existing literatures. The inclusion of camptothecin and nydroxypropyl-β-cyclodextrin is studied by the system, and the experimental results show that more information of the same sample can be obtained when combines photoacoustic phase spectrum with photoacoustic amplitude spectrum.

Method of characterizing and testing the optical performance of metal grid transparent conductive films (MG-TCF) has been established. Utilizing a charge coupled device (CCD) optical imaging device, light transmittance values of MG-TCF can be obtained by translating the CCD light response information into the light information. The average transmittance on different size scales, printed line width and the line edge roughness have also been established. Further more, combined with 3D graphical technique, the 3D transmittance display on pixel-level scale has been set up. The test results of three MG-TCF samples with square grids in flexographic printing show that the deviations of the light transmittance measured by an ultraviolet spectrophotometer are less than 1%. And thought the light transmittance analysis on pixel-level scale for the samples, characteristic values defined above have been calculated and used for demonstrating the sample features. Overall, the established method can characterize the MG-TCFs′ optical properties and give a more detailed analysis.

Reflection filters have important application in optical communication, optical imaging, and hyperspectral remote sensing. This paper intendes to design a reflection multichannel filter consisting of metal and dielectric films on the basis of the unique characteristics of one-dimensional photonic crystals with defects and the corresponding band gap theory. The working frequency range of the multichannel filters can be calculated by photonic band gap theory. The number of channels is determined by the number of periods of the “photonic crystal” defects. The channel positions can be established through the equivalent phase thickness method. Compared with the conventional design method of reflection filters which is mainly based on experiences, this design method based on the photonic band gap theory can find the design idea and theoretical interpretation of the multichannel reflection filter from the point of “photon”.

GaN thin films are grown on patternted 2 inch (5.08 cm) Si(111) substrates by metal organic vapour phase epitaxy (MOVPE). AlN interlayers with different thicknesses are introduced between the compostion-graded AlGaN buffer layers and the GaN seed layer in different samples, and the influence of AlN interlayer on the growth of GaN film is investigated. The results indicate that the full widths at half maximum (FWHMs) of (002) and (102) X-ray diffraction (XRD) rocking curves as well as the crack density are improved obviously with increasing AlN interlayer thickness. The AlN interlayer can change the growth mode of GaN seed layer. GaN seed layer tends to grow in islands mode with a thicker AlN interlayer. This leads to epitaxial lateral overgrown of subsequent n-GaN, which can decrease the density of dislocations and the residual tensile stress of GaN film. Besides, a new method for studying the morphology and growth mode of GaN seed layer by observing yellow luminescence using fluorescence microscope is presented.

Aiming at the defect of traditional spectral dimension reduction method, a new method based on the matrix theory is presented. The matrix is the revision of the matrix R theory defined by Cohen. Object spectral reflectance can be decomposed into the fundamental spectrum and the metameric black spectrum, and then linear dimension reduction is carried respectively. Three basis functions of the fundamental spectrum whose percent variance reach 100% are the orthogonal result of the color-matching functions multiplied with illuminant. The basis functions of the metameric black are derived by principal component analysis. Results of experiment show that the proposed model improves spectral and colorimetric accuracy of reconstructed spectra and satisfies the requirement of spectral color reproduction.

In order to simulate the visual effects caused by the change of visual distance, the visual acuity and contrast sensitivity function are researched. The principle of visual acuity and the test method of human contrast sensitivity model are analyzed. Considering of human vision characters, the visual acuity blur algorithm has been presented. It is able to simulate the visual blurred effect, when the visual distance is increased. This algorithm can be used to observe the gray object. Simultaneously the other algorithm is also presented based on contrast sensitivity model, it is capable of simulating the multi-scale characteristics of human visual perception, the visual characteristic of low-pass and band-pass filter, local contrast adaptability and color overlay. When the visual distance is increasing, it is able to simulate the visual blur effects to observe color objects.