A single-walled carbon nanotube combined with an organic red light material by a solution spin coating method to produce a red light detector.The influence mechanism of single-walled carbon nanotubes on PBDTTT-F∶PCBM bulk heterojunction active layer film and the photoelectric properties of red photodetector were studied. The performance of the device was characterized and optimized by atomic force microscopy, fluorescence spectroscopy and ultraviolet-visible absorption spectroscopy.When single-walled carbon nanotube is the optimal doping ratio 1.5 wt%, the responsivity of the detector is 535 mA/W under the red light illumination, the detection reaches 3.8×1012 Jones, and the external quantum efficiency reaches 104%. The results show that the combination of single-walled carbon nanotubes and organic red-light materials can improve the aggregation and crystallinity of organic conjugated polymers and enhance the absorption of light, provide high-mobility charge conduction channels for the active layer and optimize the interpenetrating network morphology. At the same time, the multi-exciton generation effect of carbon nanotubes is utilized, the photoelectric performance of organic photoelectric detectors has been greatly improved, the external quantum efficiency exceeds 100%, Providing reference for further development of inorganic-organic photodetectors.

In view of limitations of the Gaussian model for describing star energy distribution, based on the radiation characteristic of stars and the imaging properties of star tracker, an improved skewed normal distribution model of star imaging was proposed and its key parameter vector was determined. The Kalman filtering was designed to estimate the characteristics of star spot. Then, based on the characteristic that the stellar imaging process of star sensor is a stationary random process, the state space composed of the characteristic of star spot was established and the optimal estimation value of the characteristics in the least square sense was obtained. Finally, the parameter optimization of star point imaging model was achieved by using look-up table method. The result of the ground star observation shows that the Kalman filter can estimate the characteristic quantity quickly and effectively. Compared with the Gaussian model, the improved skewed normal distribution model has higher simulation accuracy for the energy distribution of the star spot.

A heterodyne all-fiber optical phase-locked loop is designed to suppress the relative frequency noise of two semiconductor lasers in passive resonator fiber gyros. The relationship between the bias stability of the passive resonator gyros and parameters of the optical phase-locked loop is established and analyzed. Then the mathematical model of the heterodyne digital optical phase-locked loop is built and simulated. Finally, the performance of the designed system is validated with experiments. Which generate a remarkable meaning of the multi-laser system used for all-fiber passive resonator gyros. The frequency difference between the two lasers is locked to the frequency of the reference source, and the deviation amplitude between the beat frequency of the lasers and the resonance frequency of the fiber ring resonator is successfully reduced by more than 15 dB.

In view of the signal demodulation of the Mach-Zehnder fiber optic interference structure, the influence of polarization fading on the demodulation of the 3×3 coupler is theoretically analyzed. It is found that the key to the demodulation of the ellipse fitting estimation method is to accurately obtain the elliptic expression of signal Lissajous figure. A polarization processing method based on morphological filtering is proposed, which uses the erosion and expansion to filter out the noise points in the elliptic pattern, then uses the edge detection method to extract the elliptical outer contour, and then uses the least squares numerical estimation method to solve the ellipse. And finally the differential cross-multiplication method is used to complete the phase reduction of the disturbance signal. The simulation results and field experimental data prove that the method is effective and effective. Compared with the traditional polarization processing method, the cost is saved, and the stability and accuracy of signal demodulation are effectively improved.

The challenge of detecting the dim small target in complex scene is to suppress the edge interference and the noise. A dim small target single-frame detection method based on structure tensor analysis is proposed. By adopting the structure tensor, which can measure the different local structure information, the structure tensor response map is calculated by employing the eigenvalue matrix of the structure tensor and the mean filter. A gray difference map is computed by adopting difference of Gaussians band-pass filter. By normalizing and fusing the two maps, the final response map is obtained. The target can be detected by segmenting the final response map with an adaptive threshold. Experiments with the standard infrared and visible datasets are performed including the different scenes such as sky, sea etc. Results demonstrate that the proposed algorithm can suppress background and nosie effectively, and detect targets efficiently and accurately in comparison with several typical methods.

Aiming at the problem that the image dehazing algorithm has halo phenomenon in depth discontinuity and legacy residual fog in the distant area, this paper proposes a single image dehazing algorithm based on fusion and Gaussian weighted dark channel. Firstly, using the characteristics of image morphology gradient, the morphological gradient image and the dark channel image are linearly fused to obtain the fusion dark channel. Secondly, the adaptive Gaussian weight parameter is constructed to pixel-by-pixel process the fused dark channel image to obtain the coarse transmission, and the L1 regularization is used to optimize the transmission. Finally, the haze-free image is restored by the atmospheric scattering model and the restored atmospheric light value. Experimental results show that the proposed algorithm can recover the details of the image and suppress the halo phenomenon. The objective comparison with several typical algorithms proves the feasibility of the proposed algorithm.

An adaptive-kernel collaborative representation method based on spatial-spectral joint clustering for hyperspectral anomaly detection is proposed, which is well used to solve the abnormal interference in space-spectrum information. The algorithm gives full play to the filtering characteristic of Density-Based Spatial Clustering of Applications with Noise (DBSCAN) for outliers, and is applied to space-spectrum processing. On the basis of removing abnormal spectrum by DBSCAN clustering, random projection for reserved subsets is used to reduce the dimension of the data, so spectral noise and spectral redundancy can be solved properly. Considering the influence of background outliers on collaborative representation detection algorithm, DBSCAN clustering is used to remove the clutter points in the local background pixels. Furthermore, the influence of background dispersion on the selection of kernel parameters is studied. By comparing different kernel estimation methods, an adaptive kernel measure method based on average difference is proposed. The proposed algorithm is used to simulate three sets of AVIRIS and ROSIS data and compared with the international mainstream anomaly detection algorithm, the results show that the proposed algorithm has a good detection performance.

Aiming at the problems of high complexity, poor real-time performance, too many input parameters and the fusion model affected by the prior knowledge on existing infrared and visible image fusion algorithms, a Poisson fusion algorithm of infrared and visible images is proposed. In the algorithm, the expected gradient of the Poisson fused image is obtained by fusing the gradient of source images with the absolute maximum rule. The average fused image is decomposed into initial values and boundary conditions of the iteration. The Poisson fused image is reconstructed by solving the Poisson equation with the Jacobi iterative solution. For the two fusion needs of high quality performance and high real-time performance, optimal numbers of iterations are determined by experiments. In comparison with classical fusion algorithms, the proposed algorithm has batter performance for both quality-first fusion applications and speed-first fusion applications.

The traditional continuous zoom middle wave infrared optical system is improved by the separation optical compensation method. The zoom group and the compensation group are separated independently to realize zoom and compensation, and the middle wave infrared optical system satisfies the ultra long focal length (916.2 mm), the ultra large field of view (36°) and the miniaturized demand of continuous zoom optical system. In zoom, the zoom compensation curve is smooth, no turning point, and the image surface is stable. The envelope of the optical system is within the range of 335 mm×118 mm (local 169 mm)×100 mm (partial 168 mm), the system is compact. The image quality evaluation of the optical system indicates that the image quality is good, and it can meet the requirements of the thermal imager.

According to the characteristics of directional polarimetric camera optical system, the ghost distribution characteristics of the instrument was analyzed. The optical working surface that could produce severe ghost images was determined through the optical design software CodeV combined with ZEMAX, and the ghost image of the experimental measurement was marked. On this basis, using the relationship between ghost image system distortion and field of view, polynomial fitting method was used to obtain the full-field ghost image position and deformation of the instrument. The energy ratio between the original image and the ghost image was determined by the measured image, and the ghost correction model of the full field of view of the instrument was established. Finally, the unsaturated and supersaturated images were corrected. The results show that the proposed correction method can eliminate at least 90% of ghost.

A cascade interferometer for X-ray phase-contrast imaging composed by a Talbot-Lau interferometer and an inverse Talbot-Lau interferometer was implemented, which the self-image of Talbot-Lau interferometer being used as the source of the inverse Talbot-Lau interferometer, with the purpose to avoid the fabrication of small-period high aspect-ratio absorption gratings. Experiments validated the method,while moire fringes and intensity oscillation curves of the imaging system are obtained. The maximum visibility of the fringes was 17.4%. With the absorption grating deviating from the zero position, the visibility of the fringes decreased gradually. But it remained above 10%, when the position of the absorption grating spaned from -17 mm to 12 mm. And the angular sensitivity as a function of the sample position was discussed. Results show that the highest sensitivity is obtained, when the investigated object is close to the phase grating. This will be useful for designing an X-ray phase-contrast imaging system for applications of biomedical imaging in large field of view.

The principle of intensity correlation imaging is demonstrated in this paper. Besides, the speckle effect of illumination laser is analyzed and the influence on spectral modulus induced by speckle effect is also analyzed with the aid of simulation. The digital micromirror array is used to design the experiment. Utilizing the wavefront data measured by the adaptive optical telescope, the rotational state of digital micromirror array can be set. Hence, the information of intensity fluctuation from different targets can be obtained. Then, the image restoration can be realized using prior information iteration algorithm. The results show that the intensity fluctuation of the target speckle light field obeys the negative exponential distribution. Apart from that, the speckle light field makes the error of the high frequency part of the target spectral modulus. Using the prior information iteration algorithm can recover the target image well, and the peak signal-to-noise ratio of the target recovery image can reach up to 29.87 dB.

Based on the theory of heat conduction, a theoretical model of HgCdTe detector irradiated by pulsed laser in relative motion is established. The thermal effects of the detector at different repetition frequencies and moving speeds are analyzed and compared by finite element method. The results show that the energy of the laser is mainly absorbed by the HgCdTe photosensitive layer and the high temperature field is mainly distributed near the interface between the HgCdTe layer and the CdZnTe layer when the HgCdTe detector is irradiated by a repetitive frequency pulse laser under the relative static condition. There is almost no temperature accumulation effect when the frequency is 1 kHz and 10 kHz. While when the frequency is 100 kHz, the peak temperature increases with the increase of the number of pulses, and there is an obvious temperature accumulation effect. The position of the peak temperature shift gradually to the direction of the velocity vector with the movement of the laser spot under the relative motion. From the point of view of damage, the cumulative effect of the damage in the space area can be achieved when each temperature peak is larger than the melting temperature of HgCdTe, and as a result, the damage to multiple detection pixels can be achieved.The thermal effect of the detector irradiated by monopulse laser spot at different moving speeds is analyzed.The faster the laser spot moves, the lower the peak temperature is at the end of the pulse, the smaller of the slope of the temperature rise curve and the slower of the temperature rise.

An experiment research on the laser induced forward transfer of sodium alginate solution was carried out, and the effect of laser pulse energy, spot diameter, thickness of titanium layer and the mass fraction of sodium alginate solution on experiments of droplet diameter and surface morphology was discussed. The experimental results showed that when the spot diameter was 100 μm, the diameter of droplets was smaller, and the surface morphology was dense and clear. The range analysis showed that the mass fraction of sodium alginate solution, laser pulse energy, spot diameter and thickness of titanium layer are less important influencing the diameter of droplets. At the same time, high-speed camera was used to study the laser-induced sodium alginate solution transfer. it was found that the laser induced liquid target transfer process was accompanied by fluid multiphase dynamic behaviors.

A home-made Er: fiber optical frequency comb aimed at measurement of frequency of D1 line in Li atoms was demonstrated.The system includes Femtosecond laser, frep and fceo detection and control, Spectral broaden and Beat unit. Femtosecond laser is a home-made nonlinear-polarization-rotation mode-locked laser, oscillating at around 1 572 nm with a repetition rate of 196.5 MHz. The fceo detection is accomplished by using the f-2f beating method, the signal-to-noise ratio of fceo about 40 dB with 300 kHz. fceo controlled by changing the pump current and its in-loop frequency instability, evaluated by the Allan deviation, is approximately 3.74×10-18/τ1/2;frep controlled by changing the cavity length of femtosecond laser, its in-loop frequency instability is approximately 1.75×10-13/τ1/2. Optical spectrum is broadened and multipliered from infrared 1 520-1 607 nm to 671 nm by using highly nonlinear fiber and MgO: Periodically poled lithium niobate. Finally, obtaining the beat signal between sigle-frequency laser and optical comb about 60 dB with 1 Hz.

The beam quality and deflection angle of vertical cavity surface emitting laser arrays dependent on element number, separation and relative phase difference were analyzed via numerical modeling analysis. According to simulated results, the divergence angle of the array varies inversely with the number of array elements. The smaller the element separation, the smaller the intensity of side lobes. The larger the phase difference between the elements, the larger the deflection angle. Therefore, it is necessary to decrease element separation, increase array scale and increase phase difference between elements for designing the coherent vertical cavity surface emitting laser arrays. In addition, 3-element vertical cavity surface emitting laser arrays were designed and fabricated. Two-dimensional beam steering was achieved successfully via separate contacts which can control current injection into each element to control phase difference between elements.

According to the coupled wave equation of grating layer controlling light wave propagation, a sub-wavelength grating guided mode resonance filter was designed. By tuning the thickness of air layer, the filter can tune the wavelength of 75 nm, and the linewidth is below or the same as 1 nm. The resonant wavelength tunable filter is integrated with a Vertical Cavity Surface Emitting Laser (VCSEL) of central wavelength of 1.55 μm, creating a lasing wavelength tunable VCSEL. It is found that the tuning range of lasing wavelength is identical to that of resonant wavelength tunable filter, and the wavelength of lasing wavelength tunable VCSEL is equal to that of resonant wavelength tunable filter at the same thickness of air layer. The VCSEL can choose both the lasing wavelength and the transverse mode of output.

In order to realize the perfect absorption of 3~5 μm mid-infrared wave, a tunable mid-infrared broadband absorber based on W/VO2 periodic nanodisk array is designed in this paper. The effects of structural parameters on the absorption performance are calculated by the Finite-Difference Time-Domain. With the optimal structural parameters, the absorber is polarization-independent and exhibits wide-angle absorption. The absorptivity is over 99% in the range of 3.1~3.6 μm, and the maximum absorptivity is 99.99%. At low temperature, the absorber presents a perfect absorption because the magnetic field is trapped in the center of each cell's VO2 dielectric layer. While at high temperature, the VO2 film is converted to metallic phase in which the absorber displays a strong reflection. The absorption difference between high and low temperature is up to 78.8%. The absorber effectively compensates for the shortcomings of the traditional absorber with a narrow absorption band and inability to regulate the absorptivity. The result of this study is of valuable reference to the application of mid-infrared optoelectronic devices.

An optical waveguide interference chip with a multi-layer planar structure was designed, and the integrated chip was fabricated successfully after its structure and the material parameters were optimized using the mode theory of optical waveguide. Far-field interference fringes with a high contrast are achieved by the dual-guide waveguide structure inside the chip. Within an experimental error, experiments demonstrate that the interference fringe pattern generated from the integrated chip can be explained and predicted by Young′s double-slit theory, and the fringe moves under a minor environment change. For humidity and alcohol gas, the detection sensitivity of the chip can reach about 100 ppm level with enough temperature stability during estimate test, which demonstrates its potential applications in sensing environment gas with low concentration and provides a new platform to develop an integrated gas sensor with high sensitivity.

The temperature-dependent photoluminescence characteristics of the strained GaInP quantum well laser structure were studied in the paper. 9 nm Ga0.575In0.425P quantum wells were selected for the active region of the laser. N ion implanting and rapid thermal annealing at 730°C were used to induce quantum well intermixing in the active region. The photoluminescence characteristics at 10 K~300 K shows that the blue-shift of photoluminescence spectra at 300 K did not occur in the samples only subjected to rapid thermal annealing or N ions implantation. While for the sampels with the N ions implantation and annealing, blue-shift was found to be increased with the annealing time. Addtionally, the photoluminescence spectra of different samples differed greatly at low temperature conditions, both single and double peaks were observed in the photoluminescence spectra. The short wavelength peak in the double photoluminescence peaks was deduced to be caused by the recombination of intrinsic excitons, and the long wavelength peaks were deduced to be caused by the recombination between the electrons in order region and the holes in disordered region. This study can provide a new research idea for the relationship between long-term reliability and low temperature characteristics of semiconductor lasers.

Utilizing the sintering method with shielding gas, a double semiconductor underlayer carbon nanotube (DSU-CNT) film cathode was fabricated, where stripe silver electrode was formed with the sintered silver slurry, while ZnO and TiO2 blending underlayers of the same width were parallel-arranged over stripe silver electrode surface, with the CNT film layer being prepared over the above underlayers. Due to better protection from oxidation by the shielding gas, no CNTs in CNT film layer were damaged, and ZnO and TiO2 particles were also shielded in the sintering process. Thus, improved electron emission characteristics of DSU-CNT film cathode were achieved, and the electron emission stability was also efficiently enhanced. As compared to the common stripe silver electrode CNT cathode, the turn-on electric field of DSU-CNT film cathode could be reduced from 2.09 V/μm to 1.91 V/μm, the maximum electron emission current could be increased from 1 653.5 μA to 2 672.9 μA. With the same electric field of 2.69 V/μm, the emission current of common stripe silver electrode CNT electrode was only 421.1 μA, while that of DSU-CNT film cathode could reach 723.5 μA. Seen from the experimental curves of emission current stability, the stable electron emission for DSU-CNT film cathode was realized, which proved that ZnO and TiO2 blending underlayers could be used in the vacuum environment. A satisfactory emission image was obtained, which indicated that the fabrication of DSU-CNT film cathode was feasible and the proposed DSU-CNT film cathode was a suitable electron emission cathode.

A modified polarization bidirectional reflectance distribution function model was proposed based on the combination of the micro surface scattering model and the Kubel-Munk theory, which combines the mirror scattering and diffuse scattering to characterize the effect of the polarization scattering characteristics of the surface of the object on the extraction of the target polarization information. The mathematical model of complex refractive index, azimuth angle, detection angle and incident wavelength is used to inverse the complex refractive index of the base material. In combination with practical applications, a series of polarization detection experiments were carried out on the target surface under different influence factors by using FD-1665 polarimetric imager. Finally, the numerical simulation results are compared with the measured data. The polarization characteristic curve of the material is in agreement with the measured data. It shows that the revised model has high accuracy. The model can provide theoretical support for the follow-up polarization monitoring and target recognition.

In order to investigate the influence of the surface deviation axicon on the propagation characteristics of the non-diffracting beam, three deviation models relative to the ideal, which are concave to the inner side, convex to the outer side and hyperbolic distribution of the apex of the axicon were established. The amplitude transmittance function was deduced, and the emergent light field and intensity distribution of plane wave through the three kinds of axicon lens was analyzed and simulated on the basis of Fresnel diffraction theory. The results show that the intensity of the light field decreases, the focal length is prolonged, the light field of the longitudinal section gradually diverges and the diameter of the center spot is gradually increased along the axis when the generatrix concave to the inner side. The intensity of the light field increases, the focal length becomes shorter, the longitudinal section of the light field gradually converges and the diameter of the center spot along the axial becomes smaller when the generatrix convex to the outer side. When the vertex of axicon is distributed in hyperbola, the light field oscillation intensifies, the field intensity and the focal depth are almost constant and the longitudinal section of the light field gradually diverges and then returns to uniform distribution. The study will provide a theoretical basis for analyzing the influence of the machining error of axicon lens on the propagation characteristics of non-diffracting beam, and has a reference significance for further supplementing the diffraction field theory of non-diffracting beam and broadening the range of its engineering application.

AAO/Ag NPs light absorber model based on porous anodic aluminum oxide and silver nano particles was designed and analyzed by employing finite-difference time-domain method. AAO/Ag NPs composite samples were prepared by physical vapor deposition method, and the optical absorption curves of the samples with different experimental parameters were characterized and tested. Results show that the light absorbance of the AAO/Ag NPs composite is as high as 98% in the range of 400 nm to 2 500 nm, and the high light absorbance is almost independent of the oxidation of silver nano particles. Theoretical calculation and test results show that the more particles are deposited inside the porous anodic aluminum oxide hole, the deeper the particle deposition, the larger the silver nano particles size range, the higher the light absorbance. The porous anodic aluminum oxide template effectively reduces the reflectivity of incident light, and the Ag film on the surface of porous anodic aluminum oxide effectively reduces the loss of incident light.

Aiming at the problem that nonuniform thickness of sputter deposited film on large-caliber optical components, the ion beam sputtering planarization layer was used to improve the surface roughness of the optical elements. The film thickness of the center and edge of optical elements depositing surface was measured by the film thickness detector, and the dwell time ratio of the center to edge was calculated. The dwell time distribution was fitted by MATLAB, and the value was corrected by the obtained data step by step. The experimental results show that, when the dwell time ratio is revised to -26.6%, uniform film can be achieved on optical elements with a diameter of 300~600 mm. Taking a Si film on the surface of fused silica as an example, the experiment is carried out for 6 h, the film thickness is 212.4±0.3 nm, and the film uniformity can reach up to 0.4%.