Atmospheric temperature is the basic parameter for the detection of atmospheric fine structure， and obtaining high-precision atmospheric temperature profile is crucial for weather forecast and climate research. In this paper， the self-developed polarization high-spectral-resolution lidar is used to realize the all-day and high signal-to-noise ratio measurement of atmospheric temperature. The algorithm by combining polarization high-spectral-resolution lidar and microwave radiometer are proposed by linear splicing method， and the complementary advantages of the two are realized. The results show that the polarization high-spectral-resolution lidar can realize the effective detection of atmospheric temperature at a distance of 4 km， and the error is mainly within ±2 K. The detection error of microwave radiometer is relatively low within 3 km， and the error is between -4 K and -2 K above 3 km. After splicing， the error is ±1 K within 3.5 km， and the correlation increases from 0.95 to 0.97. The results show that the lidar can effectively detect the atmospheric temperature in the boundary layer. Through the integration with the microwave radiometer， the blind area problem of the lidar can be solved， and the detection accuracy of the microwave radiometer can be improved.

In response to the measurement requirements of turbulence in the study of cloud precipitation physics， a turbulence parameter characterization method based on digital holographic interferometry to measure the microphysical fluctuation of liquid cloud is proposed. Since there is no need to assume the distribution function of the cloud droplet spectrum and adjust related parameters， digital holographic interferometry can obtain the microphysical fluctuations of the liquid phase cloud affected by the actual turbulence. The fog droplets affected by steady turbulence are used to simulate liquid phase cloud droplets， and the droplet spectrum is recorded by a camera with a pixel size of 1.67 μm， and then the fluctuations of the water content and the average radius of the droplets are obtained. According to the theory of turbulence， the variance， time correlation coefficient， covariance and cross-correlation coefficient of turbulence are obtained. Finally， by analyzing the time correlation coefficients of water content at different intervals， the time scale of the turbulent field is 100 ms. Under the condition of a fixed sampling interval of 71 ms， the time correlation coefficient of water content at different initial times is analyzed， and the maximum deviation of the fluctuation from the average value is 23%， which proves that the flow field in the measurement area is steady turbulence. This method can provide an effective measurement method for studying the characteristics of liquid cloud microphysics and turbulence and the mechanism of their mutual influence.

Dense apodized fiber Bragg grating arrays were on-line fabricated on a fiber drawing tower and used for temperature detection of small-scale heat sources. The signals of the grating array sensing network were demodulated through optical wavelength time domain reflection demodulation technology and optical time domain segmented demodulation technology. The sidelobe suppression effect of Gaussian apodized grating was studied and simulated. The results indicat that the gratings with good spectral type and high sidelobe compression ratio can be prepared when the Gauss coefficient G = 4. A dense apodized grating array with the sidelobe compression ratio of 20.74 dB was fabricated with our grating array fabrication system. The temperature experiment results show that， for this apodized grating array sensing network， the time-domain segmentation can reach 1 m， the spatial resolution can reach 10 cm and the temperature sensitivity is 10.15 pm/℃. It is expected that the system can be applied to small-scale heat source temperature detection in cable corridors， subways and so on.

In the wireless ultraviolet communication system， fluorescent lamp can cause power-line interference to the system. The interference can be superimposed on the useful signal received by the photomultiplier tube in the form of a sine wave， which have a bad influence on the subsequent sampling decision stage. Firstly， this article analyzes the principle of wavelet transform to remove power-line interference noise， and gives a method to calculate the signal-to-noise ratio based on the received signal waveform. Secondly， the performance of wavelet transform to eliminate power-line interference is analyzed based on this signal-to-noise ratio calculation method. Finally， the problem of selecting the optimal wavelet basis in the process of the wavelet transform to remove power-line interference is discussed. The spectrum analysis shows that wavelet transform can effectively eliminate power-line interference of 100 Hz and 200 Hz， when the wavelet basis is sym40， the best performance in removing power-line interference is achieved， and the signal-to-noise ratio is 12.22 dB after denoising.

To extract the cavity length information of optical fiber Fabry-Perot interference signal with high precision， combined with the multi-scale subdivision function of wavelet transform， the phase information of each point of the interference spectrum is accurately extracted through the wavelet ridge， and the phase compensation is carried out by using peak information， which improves the accuracy of cavity length demodulation. Simulation results show that the demodulation error of the algorithm can reach±0.06 nm in theory. The experimental results show that the cavity length demodulation resolution of the algorithm is doubled compared with that of the least square phase correction method and the resolution can reach 0.514 nm. The demodulation resolution of the acceleration sensor experiment is up to 0.9 mg. The algorithm has a certain application prospect in the high precision measurement of dynamic and static parameters of Fabry-Perot sensor.

A thin， large aperture， high gain towed line array with weak fiber Bragg gating hydrophones is proposed. A weak fiber Bragg gating array with the same reflectivities， central wavelengths and wide 3 dB bandwidths is selected according to the principle of matched interference， and the grating spacing of the weak fiber Bragg gating array is determined according to the principle of underwater acoustic sensing for 5~10 Hz very low frequency underwater acoustic signals detection. Central wavelengths of the weak fiber Bragg gating array are uniformly shifted and the grating spacing is basically unchanged when the weak fiber Bragg gating array is coated by an optical fiber coating machine. Kevlar and polyurethane protective sheath are laid outside the weak fiber Bragg gating array by an yarn binding machine and sheath machine to form hydrophone towed array. The sound pressure-phase sensitivities of the towed linear array hydrophone unit are measured as -136.97 dB （1 rad/μPa） @ 5 Hz、-139.64 dB @ 7.5 Hz、-139.36 dB @ 10 Hz. The self noise power spectrum of the hydrophone caused by flow noise is analyzed， and the spectrum value is in the range of 45~95 dB （1 μPa2/Hz） in the frequency band of 1~100Hz under 8m/s towing speed. The experimental and analytical results show that the proposed towed line array has high sensitivity and low flow noise in very low frequency band， which is expected to increase the detection function of very low frequency underwater acoustic signals for unmanned aerial vehicles.

The Brillouin dynamic grating model is developed based on the stimulated Brillouin scattering and elastic acoustic theory. The reflection spectrum of the Brillouin dynamic grating is calculated based on the fiber Bragg grating theory， and it is demonstrated that the Bragg wavelength downshifts by Brillouin frequency shift equals the Doppler frequency shift. The reflectivity and the spectral width are calculated when the pump power ranges from 0.1 W to 30 W， the pulse width ranges from 2 ns to 10 ns and the core diameter of a single mode fiber ranges from 8 μm to 10 μm. When the power increases to 30 W and the pump pulse width reaches 10 ns， the peak reflectivity is 2.17×10-6 and 7.16×10-9， respectively. The spectral width of the reflection spectrum decreases with the increase of pulse width. When the pulse width is 10 ns， the minimum spectral width is 1.2×10-4 nm. When the fiber core diameter decreases to 8 μm， the peak reflectivity increases to 6.64×10-11. The results show that the reflectivity of the Brillouin dynamic grating is positive correlation with the power and the pulse width of the pump wave， but it is negative correlation with the core diameter of optical fiber. The spectral width of the reflection spectrum is not affected by the power of the pump wave and the diameter of the fiber core， but it is negative correlation with the pulse width.

Phase-shifting Digital Holography（PSDH），which combines phase-shifting technology with digital holography， provides a fast， non-invasive， and high-precision approach for the three-dimensional morphology or refractive index distribution of microscopic objects. Compared with the off-axis digital holography， the phase-shifting on-axis digital holography makes full utilization of Spatial-bandwidth Product （SBP） of the CCD camera. The conventional phase-shifting digital holography needs to records multiple phase-shifting holograms in a step-by-step manner， from which the artifact-free phase and amplitude images of a sample can be reconstructed. To enhance the imaging speed of PSDH， parallel phase-shifting technique （or simultaneous phase-shifting technique） was proposed， with which multiple phase-shifting holograms can be obtained at the same time. In this paper， the concept and implementation of phase-shifting technologies are introduced firstly. Then， three different approaches of parallel phase-shifting， which are based on multiple CCDs， pixelated phase-mask， and parallel beam-splitting， are reviewed. Eventually， the applications of parallel PSDH in the biomedical field， air/liquid flow visualization， surface topography， micro-/nano-scale device inspection are introduced.

Near-eye display should be miniaturized under the premise of high resolution and high refresh rate， traditional video compression schemes can not meet the demand. The relationship between critical frequency of human eye and eccentricity is quantified， and a viewpoint just noticeable difference model for matching criteria of bit-plane motion estimation is proposed. Search range of the motion estimation is optimized into two parts： time dimension and gray scale dimension. Combined with the human visual system and probability statistical analysis， supplementary matching blocks are added to replace the residual data. A video compression scheme based on bit-plane motion estimation is developed for digitally driven near-eye displays， a controller is designed with field programmable gate array as the core and a system is built for verification. The experimental results show that the compression effect on the lower five bit-planes is the most balanced， the compression ratio is 1.385， and the data transmission volume is constant， which is beneficial to hardware design. The peak signal to noise ratio is 37.658 dB， and the structural similarity is 0.975. There is no obvious difference between the restored image and the original image， which is in line with the intuitive perception of the human eye.

To solve the problem of scene classification performance caused by complex background， intra-class diversity and inter-class similarity in remote sensing scene images， a new remote sensing scene classification method based on supervised contrast learning is proposed. The method involves two stages： discriminative feature learning and linear classification. In the stage of discriminative feature learning， a supervised contrastive loss first is introduced to narrow the distance between similar scenes and increase the distance between different types of scenes， so as to improve the scene discriminative ability of intra-class diversity and inter-class similarity； secondly， a gated self-attention module is introduced to filter useless background information and focus on key scene parts for improving scene recognition capabilities with complex backgrounds； finally， the pre-trained Inception V3 branch is introduced， and the branch features are merged with the final features extracted by the original model to further enhance the feature discriminative ability for improving the overall performance of scene classification. In the linear classification stage， the classification results are obtained by fine-tuning the model trained in the first stage. Comprehensive experiments on AID and NWPU-RESISC45 datasets demonstrate the effectiveness of the proposed method.

A fast blind restoration method of QR code images was proposed based on a blurred imaging mechanism. On the basis of the research on the centroid invariance of the blurred imaging diffuse light spots， the circular finder pattern is designed. When the image is blurred， the centroid of the pattern and the position of the QR code symbol can be quickly detected by methods such as connected components. Moreover， combined with step edge characteristics， gradient and intensity characteristics， edge detection technology， and optical imaging mechanism， the defocus radius of the blurred QR code image can be quickly and accurately estimated. Furthermore， the Wiener filter is applied to restore the QR code image quickly and effectively. Compared with the other algorithms， the proposed method has improved deblurring results in both structural similarity and peak signal-to-noise ratio， especially in the recovery speed. The average recovery time is 0.329 2 s. Experimental results show that this method can estimate the defocus radius with high accuracy and can quickly realize the blind restoration of QR code images. It has the advantages of rapidity and robustness， which are convenient for embedded hardware implementation and suitable for barcode identification-related industrial Internet of Things application scenarios.

Aiming at the problems of strong background noise and indistinct detail contour features in polarization fusion image of dim and weak targets， considering to the difference of gray level between Gaussian background noise and target contour in degree of polarization image， a denoising algorithm based on noise template threshold matching is proposed. Analyzing the gray correlation between the sub-image of pure noise and the sub-image of target contour in the angle of polarization image， a denoising algorithm based on Region Gray Correlation Matching （RGCM） is proposed， compared with the traditional denoising methods， the RGCM algorithm can effectively remove a large amount of background noise and retain the target contour features better. The experimental results of polarization image fusion further prove that the algorithm proposed in this paper can not only improve the contrast of dim and weak targets but also significantly improve the image quality in polarization fusion enhancement image.

To obtain an improved optimal solution， a nonnegative matrix factorization method based on abundance and endmember constraints for hyperspectral unmixing is proposed. First， considering the sparseness of the abundance matrix， a weighted sparse regularization is introduced to the Nonnegative Matrix Factorization（NMF） model to ensure the sparseness of the abundance matrix. The weights are updated adaptively according to the abundance matrix. Second， given the priori knowledge of the distribution of adjacent pixels， a total variation regularization is further added to the NMF model to promote the smoothness of the abundance map. Finally， a new constraint given by a potential function from the Markov random field model is introduced to improve the spectral smoothness of the endmembers. Experiments are conducted to evaluate the effectiveness of the proposed method based on three different data sets， including a synthetic data set and two real-life data sets （Jasper Ridge and Cuprite） respectively. From the experimental results， it is found that the proposed method got better performances both on the spectral similarity and the estimation accuracy for abundance.

Aiming at the problems of high false alarm rate and single oil type identification during oil spill detection on the sea surface， based on the Fresnel theory， the polarization degree model of oil spill on rough sea surface under different azimuth angles and zenith angles is established， and its influence on polarization degree distribution is analyzed. A visible light polarization bidirectional reflection distribution test device is set up outdoors， the visible light polarization degree images of four typical marine oil spills， including heavy oil， crude oil， gasoline and diesel are obtained at different azimuth angles and zenith angles. The difference of polarization degree of different oils is analyzed by extracting image gray data， experimental results show that the theoretical model is correct. The experimental results show that the polarization characteristics of visible light are obviously different with different oil spills， and the polarization contrast is generally higher than 5%.The use of visible light polarization to distinguish oil species is a useful supplement to traditional oil spill detection methods and is of great significance to improve the ability of marine pollution control.

In order to simultaneously measure the multi-point velocity of a plane target in the range of 5 mm in material dynamics experiments or structural response research， a laser transmitting and receiving probe with spatial resolution for photonic Doppler velocimetry is developed based on the dense fiber array and double telecentric lens. The optical design and structural design are described， and the installation and testing of the probe are performed. The test results of output spot characteristics show that the vertical axis magnification of the probe is consistent with the design value. The minimum diameter of the spot at the focusing position is 109 μm and the maximum is 202 μm. The test results of the receiving efficiency of the probe to the diffuse reflection target show that each fiber in the probe is not crosstalk， and the receiving efficiency of the fiber near the center is large， while that of the two sides is small.

Due to the fast-moving measured online object，the captured deformed fringe patterns with motion blur may lose the phase information. Therefore， by adjusting the CCD image acquisition mode ，the CCD acquisition frame rate can be increased to adapt to the online measurement of fast moving objects. In order to obtain high-resolution deformed fringe patterns， this paper adopts a super resolution reconstruction method based on the maximum a posteriori， using Gauss and markov-gibbs random field models to construct posteriori probability of the high-resolution deformed fringe pattern， the optimal estimation of high-resolution deformed fringe patterns is obtained as the result of minimizing the objective function. In this way the deformed fringe patterns can be purified. Finally all the purified equivalent phase-shift deformed fringe patterns are used for online 3D reconstruction. The experimental results prove the effectiveness of this method. The proposed method has good application prospects in high-precision and fast online 3D measurement.

A micro-angle measurement method based on Fabry-Perot etalon is proposed. Particularly， by calculating the displacement of center of the imaging concentric rings and the focal length of the imaging objective lens， the micro angle of the deflected mirror is obtained. The evaluation model of the micro angle uncertainty， based on the uncertainty components of the center displacement and the focal length of the imaging objective lens， is constructed. The Fabry-Perot etalon with an interval of 2 mm is selected to carry out the experimental research on the measurement of micro angles， and the data is processed. The experimental results indicate that the maximum measurement uncertainty is 0.132" and 0.045" in the range of 600" and 40"， respectively. The proposed method can provide a reference for the realization of the self-calibrated， higher-accuracy micro-angle measurement.

The method of Fabry-Perot resonant cavity （also called F-P cavity） is exploited to measure the optical transmission loss of SOI waveguides and the fiber-chip butt-coupling loss， with which three SOI waveguide channels having the same size and a length of 8.37 mm are measured. Then， the average value of SOI waveguide optical transmission loss/butt-coupling loss and the measurement accuracies are obtained， and the standard deviation of the measurements is very small. Another SOI waveguide with a length of 12.5 mm is measured using an automatic temperature control scanner and both the transmission losses and the butt-coupling losses of three repeated measurements are the same as one another， implying the stable measuring accuracies of F-P cavity method. The dual dependences of the measurement accuracy da/a of SOI waveguide transmission loss on the relative error dtM/tM of F-P cavity output extinction ratio and the relative error dR/R of the Fresnel reflection coefficient of SOI waveguide end-face are theoretically modelled. The simulation results show that the changes of SOI waveguide refractive index， the upper/lower cladding layers and core layer have no impacts upon the measurement accuracies of both the optical transmission loss and the fiber-chip coupling loss.The numerical simulation results are consistent with the experimental results.

A compact reconfigurable optical filter based on silicon-on-insulator with large bandwidth tuning capability is designed in this paper. The device is based on triple-ring-assisted Mach-Zehnder interferometer. The bandwidth and center wavelength of the device can be tuned at the same time by reasonably changing the phases of the microring resonators through the thermo-optic effect of silicon. The performance of the proposed device is simulated by finite difference time domain method. The simulation results show that the tuning range of the bandwidth is 1.4 nm to 10.6 nm， which accounts for 11.5% to 85% of the free spectrum range. The stopband extinction ratio is greater than 20 dB， and the passband loss is 0.4 dB to 0.7 dB， the footprint of the device is about 40 μm×60 μm.

Laser cleaning processing monitoring is essential to accurately remove the rust layer and effectively avoid the damages of the metal substrate. The variations between the number of cleaning and the rust cleaning rate at different spot overlap ratios on 30 mm×30 mm Q235B steel plate were studied by image processing to obtain the optimum spot overlap ratio of 50%. The changing trends of the Pearson correlation coefficient following the number of cleaning on 0.47 mm×0.47 mmQ235B steel plate were studied by Laser-induced Plasma Spectroscopy （LIPS） and the optimum number of cleaning was obtained under different thick dust layer. On this basis， the cooperation of image processing and LIPS is not only to dynamically correct the optimum number of cleaning but also to cover the shortage that image processing can not control the process of laser cleaning accurately. The results show that the cooperation of two methods can monitor the process of laser cleaning on a large area of Q235B steel plate and achieve high-quality laser cleaning with a 99.1% cleaning rate.

A figure-8 cavity wavelength-tunable mode-locked Ytterbium-doped fiber laser based on nonlinear amplification loop mirror is reported. When pump power is 240 mW， the dissipative soliton is output with a central wavelength of 1 064.1 nm， 3 dB bandwidth of 7.7 nm， repetition rate of 18.8 MHz， optical signal noise ratio of 71.2 dB and pulse duration of 867 fs， respectively. In addition， wavelength tunable of the mode-locked fiber laser at 1 032.8~1 065.1 nm and 1 037.4~1 041.9 nm can be achieved by adjusting the polarization controller and pump power respectively. The characteristics of the spectra and pulses in different mode-locked states are explored， and a Gaussian pulse whose time bandwidth product is close to the Fourier transform limit is obtained. The fiber laser is simple in structure and easy to tune， and has a stable performance， which provides technical reference for achieving wavelength tunable and dissipative soliton mode-locked.

Aiming at improving the accuracy and stability of the pose estimation when the target points located in the planar， quasi-planar and quasi-linear case. In this study， we propose an iterative solution for singular configuration of target points. The main idea of the algorithm is to select two farthest points as the basic reference points， and divide n points into n-2 three-point sets. Then， the auxiliary points are constructed according to the geometric relationship of the three-point set， aiming to increase the geometric constraints of the perspective similar triangle algorithm， and obtain a more accurate initial value. Finally， the simplified EPnP algorithm is combined with Gaussian Newton algorithm for optimization. Experiments conducted on synthetic data and real images show that when the number of planar target points n=4， the average image re-projection error of this algorithm is 0.003 mm， compared with the orthogonal iterative algorithm， EPnP algorithm and IEPnP algorithm， which is 0.062 mm， 0.324 mm and 2.238 mm respectively， this algorithm effectively improves the accuracy and stability of the pose estimation of the target point in singular configuration.

In order to solve the easy-broken structure， low energy efficiency and heat dissipation of the traditional X-ray tube with filament based on thermionic cathode， a novel light-controlled pulsed X-ray tube device is deostrated in this paper. By matching the parameters of photocathode and light source， S20 cathode with high quantum efficiency and LED with 460 nm wavelength were selected. At the same time， the overall structure design of the X-ray tube is determined by the simulation. Finally， the maximum tube current of 2.37 mA is realized， the electron emission efficiency of photocathode is 0.288 mA/lm， and the output X-ray energy is adjustable from 0 to 25 keV. In addition， based on the characteristics of easy-access to be modulated of the light-controlled pulsed X-ray tube， different frequencies input signal restoration experiment and arbitrary contor X-ray restoration experiment was carried out.

Based on Fraunhofer diffraction integral formula， using convolution theorem and the property of zero-order Hank transform， the analytical mathematical formula of light intensity distribution on the back focal plane of the lens after the fundamental transverse mode Gaussian beam perpendicularly enters the axicon-lens combination optical system is derived， and the mathematical relationship between the bottle beam intensity distribution and the main optical parameters in the axicon-lens combination is established， which provides theoretical support for the rapid simulation of bottle beam intensity distribution and the design of optical system for generating bottle beam. According to the derived formula， the numerical simulation and experiment are carried out， obtaining a uniformly distributed bottle beam with similar ring size， respectively， which verifies the correctness of the theoretical results.

In order to further expand the functional characteristics of micro nano periodic superstructure and meet the high-precision design requirements of optical periodic superstructure，based on the Multi-resolution Time-domain Method（MRTD）， starting from Maxwell equation and deducing the surface composite scattering field of the micro-nano three-dimensional hemispheric optical periodic structure， a good agreement is presented when the calculation results are compared with the results of the FDTD method. The surface field distribution of the mico-nano three-dimensional hemispheric optical periodic structure is given and the differential scattering cross section of mico-nano three-dimensional hemispheric optical periodic structure is numerically calculated. The influence of the filling material， hemisphere size， hemispheric distance and other parameters on the surface scattering field is simulated and analyzed. The following conclusions are obtained： the electric field distribution under P polarization could highlight the surface structure unit profile of periodic structure； the scattering field increases with the incident angle， and gradually decreases in the direction of the mirror scattering angle； the peak number of the scattering field of filled unit is consistent with the number of filling units in the detection range when the radius and wavelength values are equivalent； with the increase of the filling hemisphere distance， the maximum value of the scattering field increases successively， and the angle interval corresponding to the maximum value decreases sequentially.

The relationship between the characteristic parameters of photon jet and those of particles is studied， including the mechanism in the generation of photon jet under different polarization modes of resonant and non-resonant scattering. The dependence of the photonic jet characteristic parameters on the refractive index and particle parameters is numerically analyzed with the Lorenz-Mie theory calculation. The effect of resonant scattering on the photonic jet is studied， showing the contribution from the resonant partial wave. Besides， a comparison is made for the photonic jets in linearly- and circularly-polarized irradiations. The results show that resonant scattering affects the photonic jet by narrowing its transverse width， shifting the focus inward to the particle surface， shortening the longitudinal length， enhancing the intensity at the focus and making the field distribution more complex. The relative intensity of the radial and transverse components of the electric field is different under TE and TM resonances. The polarization state of the incident light affects the transverse distribution of the photonic jet only. By controlling the parameters of incident light and particles， the characteristic parameters and the field distribution of the photonic jet can be modulated. The study provides theoretical reference for the applications of photonic jet.

The photoacoustic cell， as the core component of the photoacoustic spectroscopy gas detection system， directly affects the detection accuracy of the system. Based on the classic cylindrical photoacoustic cell， the finite element analysis software is used to combine the two physics of pressure acoustics and thermoviscous acoustics and build a model to simulate the acoustic-thermal coupling process in the photoacoustic cell. The effect of different geometric parameters of the resonant cavity and buffer cavity on the performance of the photoacoustic cell is compared through simulation， and then， the optimal size is determined. The simulation results show that the length and radius of the resonant cavity and the buffer cavity will affect the resonance frequency and acoustic pressure. After fully considering the comparison results and the difficulty of industrial manufacturing， the optimal length of the resonant cavity is selected as 120 mm， the optimal radius is 3 mm， and the buffer cavity radius is 35 mm. On this basis， a photoacoustic cell with a rounded connection between the resonant cavity and the buffer cavity is designed. Compared with the right-angle photoacoustic cell with the same size， the round-corner photoacoustic cell has more advantages in improving the photoacoustic signal and reducing the flow noise interference. The quality factor is increased to 1.109 times， the cell constant is increased to 3 635.1 Pa·cm/W， and the acoustic pressure is increased to 1.26×10-5 Pa. In the concentration detection of methane gas， the system sensitivity can reach 0.87 ppm， and the detection result is ideal， which meets the requirements of high sensitivity. Therefore， the performance of the round-corner photoacoustic cell has been significantly improved， which can provide a reference for the optimal design of the photoacoustic cell.

A thermochromic film was prepared with VO2@SiO2 core-shell nanoparticles to enhance the visible light transmittance and weather resistance of thermochromic film and also decrease the agglomeration of VO2 nanoparticles prepared by thermal decomposition method. VO（OH）2@SiO2 core-shell nanoparticles were prepared by coating SiO2 layer on the surface of VO（OH）2 nanoparticles via the surface electric interaction between nagatively charged VO（OH）2 nanoparticles and positively charged NH2 groups of aminopropyltriethoxylsilane. Then a normal heat treatment of VO（OH）2@SiO2 under Ar atmosphere was utilized to obtain VO2@SiO2 nanoparticles. Subsequently optical film with good thermochromic property was prepared by coating the resin dispersion of VO2@SiO2 on well cleaned glass. The thermochromic property and the weather resistance of thermochromic film were studied . From TEM images， we find that SiO2 shell prevents the agglomeration of VO（OH）2 during heat treatment. Research on the optical properties of the film shows that the SiO2 and air of low refractive index can improve the optical properties of thermochromic films，and when the mass fraction of VO2@SiO2 nanoparticles is 10wt%， the optical performance of the composite film is the best. The protective effect of the SiO2 shell to the VO2 core obviously improves the oxidation resistance and corrosion resistance of VO2 in damp heating and acidic environment， which makes longer life of VO2 thermochromic film.

In order to obtain high-performance transparent dielectric thin films， nanocrystalline zinc-rich ZnS films were prepared on glass substrates by radio frequency magnetron sputtering with a ZnS ceramic target at room temperature， and the effect of the radio frequency power on the structural， surface morphology and optical properties of the films were studied using X-ray diffraction， field emission scanning electron microscopy， micro-Raman spectroscopy， ultraviolet-visible spectroscopy and spectroscopic ellipsometry. It is found that the radio frequency power has an important impact on the phase formation and crystallinity of the ZnSX films. With the increase in the radio frequency power， the atomic ratio of zinc to sulfur， intensity of the characteristic Raman peak and refraction index first increase and then decrease， the optical band gap of the film deceases from 3.86 eV to 3.76 eV systematically. Among the various radio frequency power values investigated， 150 W is optimal for the growth of highly crystalline ZnSX films with the cubic phase， the ratio of Zn/S of film is 1.23 close to the standard stoichiometric ratio， the average transmittance is more than 80% at visible light， and the optical refractive index of ZnSX film is 2.03 at 550 nm.