In order to research the effects of the concentration of the scattered medium on the polarization degree of the scattered light in near-infrared detection and the relation of the polarization degree of the target and the ratio of the impurity, the numerical results of the Müller matrix and the polarization degree were calculated. The results showed that the concentration of the scattered medium has significant effect on the depolarization degree of the scattered light. And then the numerical relation between the polarization degree of the target and the ratio of the impurity were discussed by building the mixed target model. The normalized polarization degree was obtained in addition. The inversion result of the ratio of the impurity can be obtained from the normalized polarization degree. The result can be applied as a new approach of the atmosphere remote sensing.

For the optical system with circular apertures, it is difficult to get the boundary radical slope of phase and the accurate sampling value in the circular domain boundary when the intensity transport equation is used to recover the original phase. An improved method is put forward, in which the equation, computation domain and boundary condition are changed, and then the phase is reconstructed by the multigrid method and corrected at last. In order to correct the reconstructed phase, the transport matrix from the reconstructed phase to the original phase is also obtained. The case of uniform illumination is simulated and it is found that the method can recover Zernike coefficients of the original phase well while avoiding complicated boundary condition and reducing computation time, and furthermore the root-mean-square value between the corrected phase and the original phase is acceptable even when noise is added.

Low-loss and flexible hollow optical fibers were fabricated based on the polycarbonate capillary. Silver and cyclic olefin polymer films were innerly coated to enhance the reflectance at objective wavelengths. By optimizing the liquid-phase coating parameters, polymer layer obtained optimum thickness for simultaneous transmission for Er∶YAG and visible pilot beams. Polycarbonate capillary based hollow fibers are flexible and safe, which makes it possible to deliver infrared laser power in endoscopic application. The transmission losses are 0.4 dB/m and 3 dB/m for the 2.94 μm Er∶YAG laser and red visible laser, respectively. The transmittance of Er∶YAG laser light is about 70% and loss of visible pilot beam is 11 dB when the fiber was sharply bent with a bending radius as small as 0.9 centimeter and bending angle at 135°. Experimental results show that cyclic olefin polymer coated silver hollow polycarbonate fiber are suitable for the delivery of endoscopic laser and visible pilot beam.

The distributed optical fiber sensing system based on Mach-Zehnder interference principle has the ability of warning the potential sabotage acts to oil and gas pipelines, and the distributed location technology is one of the key technologies. Based on the correlation theory, the location theory has been studied, the experimental system based on virtual instrument platform has been established; Several experiments has been carried out at eight different locations across 20 km sensing fiber, the results show that the positioning error could be controlled within 149 m,which can meet the practical positioning needs.

The dispersion of fiber Bragg gratings can be tunable by plating the nonuniform copper film of gradient thickness on the outer cladding of fiber grating along the axis and can be used as dynamic dispersion compensators. The fiber grating's dispersion is adjustable by changing the temperatures of the grating. A numerical model based on thermal balance equations has been used to analyze the dynamic characteristics of the nonuniform copper coated gratings. The reflection spectrum, time delay curve, and dispersion property were also analyzed for those gratings. The model has been verified by experiments.

To exploit the expressive ability of depth of field of reflection holograms according to the relationship between object and conjugate image, and using the uniform coupled-wave theory and the Bragg condition, the image blur of reflection hologram which was caused by reconstruction with white light source, was analyzed and discussed concretely, so the expressions of the color blur and linear blur were achieved. Such a difference was pointed out: when the reflection hologram was constructed by white light source, the color blurs and linear blurs caused by different dots on the reflection hologram, have different effects for the same construction image point. The expression about the depth of field of reflection hologram was advanced. A two-step large scene depth reflection hologram which is deep as 83 centimeters was obtained in experiment. Compared with large depth rainbow hologram, the three-dimensional effect of the reconstruction image is stronger. The theoretical analysis and the experimental result showed that, the depth of field of reflection hologram's reconstruction image will be affected markedly by reconstructing angle and the watching distance. When the reflection hologram was reconstructed vertically, it has the most ability to express it's depth of field.

Due to the nonlinearity of the digital projection and acquisition system, usually it is necessary for traditional approaches to eliminate high-order harmonics of the captured fringe patterns by using lowpass or bandpass filters and obtain fundamental component. A novel filtering method-post filtering for digital fringe pattern profilometry is presented based on generalized analysis model, it can reduce the influence from the nonlinear distortion of the fringe patterns and improve the accuracy of digital fringe pattern profilometry. The principle of fringe pattern profilometry and generalized analysis model are recited,a derivative process of the post filtering method is analyzed. Simulation and experimental results show that fast and precise digital three-dimensional reconstruction can be achieved by the post filtering method.

Auto-focusing is a key technology in digital instruments and computer vision. In the focusing procedure, the focusing accuracy and anti-noise capability is crucial. Evaluation functions which based on high-frequency components have many advantages, such as sensitivity and focusing accuracy. They are suitable for the real-time system,however, they are easily corrupted by noise. Therefore, a new focusing evaluation function with good anti-noise capability has been proposed. Firstly,the proposed function abstracts high-frequency components through wavelet multi-resolution analysis (MRA). Some neighbor correlation exists in each sub-band coefficients,but noise is random, so the noise coefficients have no such correlation. The new function introduces a frequency sub-band threshold, supposing that the component value below than the threshold is noise, then filter it. In this way, noise and image signal could in general be separated. Experiments have proved that the proposed function has a sharp single apex as well as high sensitivity. Furthermore, it is significantly advanced in the anti-noise capability.

A small-target detector based on single likelihood test for hyperspectral imagery is presented to detect target when there is no a priori spectral signal of background and target, which presume the maximum entropy character of target. Because of the low-probability occurrence of target compared with that of background, it can be assumed that there is no constraint by hyperspectral imagery data on the moments of target signal. Accordingly, the generalize likelihood ratio test can be simplified to test background likelihood solely under maximum entropy of target. Then, nonparametric estimation is utilized to obtain the probability density of background, which can extract information from samples more effectively. The single likelihood test based detector weakens the effect of statistic model discrepancy and avoids effect of implicit physical meaning on detection. Theoretic analysis and the experimental results on visible/near-infrared OMIS-I hyperspectral imagery verify that these algorithms are effective to detect spatial low-probability targets.

In order to advance the detection ratio of dim target in clutter background, the reason of low target detected radio from infrared image that contain both complex and flat background is analysed. And based on this analysis, an algorithm of dim target detection based on adaptive background adjusting is advanced. This algorithm uses Robinson guard filter to distill potential target point. And clutter image fuzzy membership function is defined to map the image to fuzzy plane. The background adjusting coefficient is computed by this fuzzy plane to modulate the potential target point. So the influence of the clutter background of the image is reduced. The experimental results have proved that this algorithm can obviously improve the probability of the point target detection, and it can detect dim targets within infrared image with signal-to-noise ratio higher than 1.

The certification is performed through directly testing the computer-generated hologram(CGH) which is used to synthesize the wavefront reflected by a perfect primary mirror. If the errors of computer-generated hologram are within the requirement, the certification can be realized. The principle and methods of certification by computer-generated hologram are introduced ,and its errors are analyzed. Using the computer-generated hologram written by electronic beam lithography, the compensator for 850 mm F/2 parabolic mirror is certified, and the standard aspherical precision created by the compensator is not less than the primary mirror precision synthesized by computer-generated hologram, the root mean square(RMS) error is 0.012λ. The results show that it's an effective way to certify the compensator by simulating the wavefront reflected by perfect primary with computer-generated hologram. Combining the sophisticated lithographical manufacturing technology, high-precision certification can be achieved.

Aiming at the problem of energy leakage that occurs during the course of phase-extraction by using conventional fast Fourier transform (FFT) algorithm, an novel method that acquisition interferogram is firstly tailored to a few full-period of fringes is proposed to suppress the influence of energy leakage on the precision of phase-extraction. The precision of fast Fourier transform phase-extraction algorithm can be efficiently improved by tailoring the interferogram. Furthermore, a new subdivision method, which is based on the time-shift property of fast Fourier transform, for moiré interference fringes is developed. Compared with conventional fast Fourier transform phase-extraction algorithm, this new method pioneers a larruping means for fringes subdivision and can achieve high precision. It needs only to run fast Fourier transform algorithm twice to obtain the phase-shift between two sequential interferograms. The corresponding calculating time can then be greatly saved because it does not need to intersect the fundamental frequency of interferogram from spectral domain and inversely transform it into time domain again. Numerical results show that subdivision precision can reach 10-12 level for ideal situation that the interferogram is formed by two coherent plane waves and can be tailored to a few full-period of fringes. It can reach 10-3 level when the inteferogram is formed by two Gaussian waves.

An objective characterization method for large area flicker of plasma display panel is proposed. A measuremental setup based on a photo diode and a luminance meter, was built to record the light behavior quickly and accurately. Based on model of critical flicker frequency calculation for cathode ray tube, an analytical model was built to predict the perceived large area flicker seriousness level based on the measured light behavior. The output of the analytical model had a coefficient of correlation as high as 0.98 with perception experimental results. The measuremental setup and the simulative model enable objective evaluation for large area flicker of plasma displays, it is consistent with experimental results. It helps with plasma display panel design optimization and industrial standardization.

Film preparation of a novel polymer photonic material, PPESK, was investigated systemically. The influence of solvent hydrophilicity on film quality was analized. A good waveguide film with homogeneous thickness (better than 1%) and identical refractive index (better than 0.03%) was fabricated by nitrogen atmosphere protection. The optical properties of PPESK film, including refractive index, birefringence, thermal-optical coefficient and optical loss, were measured and characterized by prism-coupling technique, and the optical loss was measured to be lower than 0.24 dB/cm at 1310 nm, and lower than 0.52 dB/cm at 1550 nm. The results showed that PPESK was a promising photonic polymer material due to its fine optical performance.

A novel scheme for linearity improvement of optical modulator is proposed for radio over fiber (ROF) system. This modulator is named ring and phase assisted Mach-Zehnder modulator (RPAMZM). A microring and a phase modulator are coupled to each arm of a normal Mach-Zehnder modulator respectively in order to compensate its sublinear characteristics transfer. Analyses under loss-less condition, loss condition and spur-free dynamic range (SFDR) are proposed. It is found that a high linearity can be achieved by properly setting the coupling coefficient under lossless condition. A corresponding SFDR of 19.68dB is achieved. When loss is considered, the main nonlinear terms, including the 2nd and the 3rd term, can be eliminated by properly setting the coupling coefficient and bias point. A corresponding SFDR of 15.74 dB can be achieved.

Using cascaded stimulated Brillouin scattering (SBS), the self-exciting Brillouin erbium-doped fiber laser (BEDFL) is a multi-wavelength source at room temperature. The multi-wavelength output of the BEDFL with a high-birefringence Sagnac loop filter is tunable by adjusting the polarization controller (PC) in the Sagnac loop. At the same time, dual Brillouin bands appear during the experiment. The influences of the bandwidth of the Sagnac loop and the pump power at the 980 nm on the multi-wavelength output are investigated in detail. A multi-wavelength band with 52 lines is achieved when the bandwidth of the Sagnac loop filter is 83.3 nm and the pump power at the 980 nm is 260 mW.

Thermal induced distortion in the gain element is the main obstacle to be overcome in the scaling of solid-state lasers to very high output powers. The method of compensating the aberration by using an intra-cavity adaptive optical system was studied. A MEMS deformable mirror using as the intra-mirror of the solid-state laser could improve the mode and output power of the laser. The effect of the intra-cavity aberration to the beaconing light form out-cavity could be measuredwith a wave-front detector and an adaptive optic system has been used to compensate the aberration. The experimental result shows that the output power is increased nearly 3 times and the beam profiles are improved obviously by closed loop automatic optimization of the adaptive optic system.

Pump and cooling scheme play an essential role in getting high bright and high-average-power output for diode pumped solid-state lasers besides the temperature distribution and thermal lens effects. Base on heat conduction equations, under the condition of conductively cooling and the same pump power, temperature and thermal-induced stress and temperature induced refractive index are analyzed in detail in one-side pump zigzag slab, one-side pump diffusion bonding zigzag slab, partially pumped slab configurations. Using ray tracing method, the OPD (optical path difference) is compared in zigzag and perpendicular zigzag plane, and the thermal lens effect is analyzed with the OPD curves. The end temperature, end deformation, end OPD are also analyzed in contrast. It is shown that the beams are diverging in zigzag plane while they are focusing in perpendicular zigzag plane, and the diffusion bonding slab can eliminate end effect in evidence. At last, the compensation method of the thermal-lens effect is also proposed.

In order to meet the requirement of seam finder and seam tracking under special conditions, using laser scanning technique, seam tracking system based on circular laser sensor is developed, cooperated with welding robot, built “hand-eye” system, and three-dimensional information for weld workpiece could be extracted, escaped from shortcomings of less information, ambiguous explanation and single tracking direction for “spot” or “line” laser trajectory. Study on calibration of vision sensor for seam position and seam tracking is carried out. Finally, real experiment for butt joints, lap joints and corner joints was carried out and the calculation precision was analyzed. The results showed, the pattern of the circular laser is different for different seam, combining with calibration results, the three-dimensional coordinates of welded joints could be determined and the precision could meet the requirement of seam tracking test.

Ultraviolet laser-induced ferroelectric domain inversion in nearly-stoichiometric LiTaO3 was investigated. The continuous ultraviolet laser with 351 nm wavelength was focused on the -z surface of nearly-stoichiometric LiTaO3, and the homogeneous electric field which was antiparallel to the direction of spontaneous polarization was applied simultaneously. It is proved that the coercive field is effectively reduced by the laser radiation. The local domain inversion induced in the laser radiation area is confirmed by the digital holographic interferometry. The investigation proves that the ferroelectric domain inversion can be locally controlled by the ultraviolet laser irradiation. It is regarded that the defect structure with jumbo size and high density in the crystal lattice is generated by the complex coaction of incident irradiation field and external electric field. The defect dominates the nucleation by reducing depolarization energy and domain-wall energy required for domain-nucleus growth and domain wall movement, and the laser-induced domain inversion is realized.

The structure, electronic properties and optical properties of zinc blende CdS and CdS∶M (M=Mg, Ni) were studied systemically from density functional theory (DFT) based on first-principles pseudopotential calculations. It showed that the M-doped material had a smaller lattice constant, which resulted in a local lattice distortion. The band structure and density of states (DOS) were further calculated, which indicated that CdS∶Ni was half metallic ferromagnetic semiconductor while CdS∶Mg was semiconductor with bigger band gap due to the introduction of Ni 3d and Mg 3s. The optical property was also studied from the calculated absorption coefficients, which showed that the absorption peaks changed obviously at the visible light wavelength area for the M-doped CdS. Furthermore, the absorption ranges was extended to even higher wavelength region for the Ni-doped CdS.

The electro-magnetic distribution when the Gaussian beam is incident into the bicrystal structure is presented, and the refraction and transmission coefficients of extraordinary light at the bicrystal interface are derived. According to dispersion relations, The relations of the incident angle, reflection angle and refraction angle equations with bicrystal parameters and wave vector are obtained respectively. The variation of the reflection angle and refraction angle with the incident angle for certain bicrystal parameters is presented by angle quations. The unique properties of amphoteric refraction, negative refraction, total transmission and total reflection are plotted and analyzed, and the crystal parameters and incident angle for these properties are analyzed. The time-averaged energy density distribution of Gaussian beam with special parameters in bicrystal is numerically analyzed when amphoteric refraction, total transmission and total reflection occur. At last the Goos-Hnchen shift of incident angle at the interface is given with different beam widths when total reflection occurs.

Spherical Sr2Al2SiO7∶Eu2+ phosphor was prepared by spraying of AlOOH/Sr(NO3)2/SiO2/Eu composite sol technique. Three-dimensional oriented dry xerosol particle was obtained due to the self-assembly of nanoscaled pseudoboehmite sol particles and SiO2 nanoparticles. Hierarchical Sr2Al2SiO7∶Eu2+ phosphor particles were obtained by sintering dry xerosol particles at 1300 ℃. XRD results show that the Eu2+ ions partially substitute for Sr2+ sites on Sr2Al2SiO7 lattice. The excitation band of 326 nm is attributed to the transition from 4f to 5d in Eu2+ ions of Sr2Al2SiO7∶Eu2+ phosphor. The emission of Eu2+ ions 4f65d→4f7 transition lies at ～500 nm.

A transmitting Fabry-Pérot light modulator for display application is proposed. Its optical characteristics are analyzed with multiple beam interference theory. The typical parameters of the light modulator for display are deduced. When the Fabry-Pérot cavity length is λc/4, almost all transmitted light is cut off, the modulator is “off” state. While when the cavity length is 0 or λc/2, corresponding light can transmit the modulator, the modulator is “on” state. It is theoretically proved that this light modulator is capable for display. Finally, one light modulator structure based on micro-electro mechanical system (MEMS) is given. Contrast ratio of this device is 150 by theoretical calculation. Result of the software simulation shows that this structure has as low as 2.4 V actuating voltage.

By using transfer-matrix method, the transmission properties of a one-dimensional photonic quantum-well structure containing defect layers with negative refractive index are studied. It is found when the number of defects is even, there are two transmission peaks in the photonic quantum well, and when the number is odd, only one transmission peak appears in the center frequency. The Q factor of the transmission peak in the center frequency advances when defect layers increase. Due to the strong localization of electromagnetic wave at defect regions, the transmission of confined states are greatly dependent on the refractive index of the defects. The refractive index of the defects is changed slightly by controlling light intensity, then the transmission of confined states is changed obviously. High-efficiency optical switches can be realized by using this property.

The cavity-field spectra of a pair coupled two-level atoms in an ideal cavity interacting with two-mode radiation field is studied with the fields both in the binomial state. The influence of the interference effect on the spectra structure is discussed in detail. The result shows that multi-peak structure appears in the cavity-field spectra when the photon number of the two-mode radiation field is equal, the three peaks of each mode spectrum approach ωi and ωi±0.7g and side peaks disappear while the fields' intensity becomes more and more stronger. It's found that when the frequency difference of the initial two mode Δ is larger than 6g (g is the coupling coefficient between the atom and the field) the interference effect of the spectra can be ignored, when Δ is smaller than 6g the interference effect should be considered. Especially when Δ is reduced gradually from 1.4g the three peaks of the mode Ⅰ and mode Ⅱ begin superpositioning, the interference effect is obvious.

Solar ultraviolet (UV) spectral monitor (SUSM) is a compact, high-precision satellite-borne spectroradiometer designed to measure the solar ultraviolet-spectral irradiance and the solar backscatter vltraviolet-spectral radiance from the atmosphere under two different work modes. The calibration setup is presented. A spectral irradiance standard lamp directly illuminates the diffuser of the solar ultraviolet spectral monitor to calibrate the solar ultraviolet spectral monitor spectral irradiance responsivity and a standard diffuser illuminated by the standard lamp as Lambert surface source is used to calibrate the solar ultraviolet spectral monitor spectral radiance responsivity. The measurement error analysis shows that the 160～250 nm spectral irradiance calibration error is 6.5%, the 250～400 nm spectral irradiance calibration error is 4.3% and the 250～400 nm spectral radiance calibration error is 5.9%. The data of solar ultraviolet spectral irradiance and the solar backscatter UV spectral radiance obtained by solar ultraviolet spectral monitor agrees with the internationally published data within ±10%.

Along with the need in military and industry, especially in certain tough and dynamic environment, image fusion need emphases to display in near natural color results and consider the requirements of human visual perception. The development of color image fusion algorithms are introduced and two representative near natural color image fusion methods based on visual characters are described, and our researches on this field are summarized in detail. The progress on real-time color image fusion system and our hardware researches are specified. Several main technologies are discussed particularly, such as multi-source image characteristics analysis, real-time image registration, post processing of fused image and so on. With current application situation of image fusion, the prospect of image fusion technique and system are forecasted.