In this paper， the selective substrate removal technology after the silicon-based metal monolithic bonding was used. The （100） crystalline silicon was bonded to （111） crystalline silicon at high temperature by hot-pressure bonding technology. The （100） crystalline silicon substrate was protected by polydimethylsiloxane （PDMS）. Then， the （111） crystalline silicon substrate was roughened to accelerate the etching rate. Finally， the （111） crystalline silicon substrate was removed by the wet selective etching. The （111） crystalline silicon substrate of GaN epitaxial substrates was selectively removed with saving the Si-based driver chip. It is a new technology for the mixing and integration of material. It is expected to be applied in the manufacturing process of self-aligned silicon-based micro-LED microdisplay devices and optoelectronic device integration.

An electro-optic switch was developed based on the lithium niobate on insulator （LNOI） platform. The structure of the LNOI waveguide， multimode interferometer （MMI） coupler and metal electrodes were carefully designed. The fabricated electro-optic switch chip was coupled with optical fiber arrays and packaged by using metal shell. The measured on-off switch time was less than 13.4 ns and the extinction ratio was about 31.8 dB. The results showed that LNOI based electro-optic switch was an excellent candidate for developing high performance integrated optical beamforming network chips used in microwave photonic radars.

Based on the interference principle of conjugated vortex beams， the relationship between the rotation angle and displacement of the interference image was theoretically analyzed， and the feasibility of the theory by optical simulation system was verified. An interferometer composed of a spatial light modulator and an improved Mach-Zehnder interferometer was designed to measure the displacement of the nano-displacement stage using the conjugated vortex beams with different topological charges.The experimental results showed that when the displacement was 100 nm， 200 nm and 250 nm， the relative error was the smallest when the topological charge was 3， which was 2.19 %， 1.28 % and 1.27 %， respectively. The research results were helpful to improve the accuracy of displacement measurement based on conjugated vortex beams interference.

A method based on deep feature to reconstruct face images was proposed in this paper. The deep features were first embedded into the W+ space of StyleGAN2， and the embedded w+ vector was optimized by gradient descent and fed into a pre-trained StyleGAN2 model to generate face image with resolution of 1 024×1 024. The experimental results showed that the reconstructed images had high visual similarity with the corresponding real face images. When using the same extraction network， the type-Ⅱevaluation TAR of the reconstructed images from LFW and ColorFeret datasets was 96.04% and 100.00% respectively when the FAR was equal to 0.1%， and the pass rates of liveness detection were 88.67% and 74.67% in two products. The proposed method could reconstruct face images in high resolution and achieve high feature similarity between real and generated face images.

In order to improve the display brightness and view uniformity of the vector light field， a metagrating structure for circularly polarized light field imaging was proposed. The effect of incident light polarization state， grating structure and incident angle on the diffraction efficiency of -1st order light were studied by simulating the structure of metagrating pixel by pixel using a rigorous coupled wave analysis method. The simulation results showed that the circularly polarized light display could make the diffraction efficiency of the grating stable and efficient. When the grating period was 500 nm， the diffraction efficiency of the grating structure based on the circular polarized light increased by 18.5% and 2.6% compared with TE and TM. The height and duty cycle of grating had a significant impact on the diffraction efficiency. Considering the difficulty of metagrating fabrication， diffraction efficiency and viewing angle uniformity， metagratings array structure with the height of 0.6 μm and duty cycle of 0.4 was designed for circular polarization. The diffraction efficiency of the system could reach more than 40%， and it had better comprehensive performance， which was a guideline for metagrating design and preparation， as well as naked-eye 3D display.

High-power LED headlights adopt fans for forced convection heat dissipation. Aiming at the problem that the size of the surrounding space of fans could affect the heat dissipation performance of headlights， finite element simulation， uniform design method and response surface analysis were combined to carry out the optimization research. Firstly， the finite element software FloEFD was used to study the influence of three design parameters on the heat dissipation performance of the high-power LED headlight air cooling system： the radial distance between the fan shield and the wall （A）， the distance between the fan inlet and the wall （B）， and the distance between the fan outlet and the radiator （C）. Then， the uniform design method was used to design the test scheme for response surface analysis， and the regression model between the three parameters and LED solder joint temperature was fitted， and the influence of the three parameters on the system heat dissipation performance was determined by Pareto analysis method. Finally， the response optimizer of Minitab software was used to minimize the LED junction temperature， and the optimal combination of three parameters was confirmed to be 8.4 mm for A， 16.3 mm for B， and 4.3 mm for C. Through the experiment of the best combination， it showed that the combination had the best heat dissipation performance. At the same time， the simulation and experimental results were consistent， verifying the reliability of the simulation.

A metal bonding technology was proposed for Au-Au thin films under atmospheric and low temperature conditions. And the effect of activation treatment time on the surface roughness of Au-Au films， the bonding quality and reliability of Au-Au films were studied. The experimental results showed that the surface roughness of the Au film first decreased and then increased with the increase of the surface activation treatment time. When the surface activation treatment time reached 20 min， the root mean square of the surface roughness of the Au film was 6.9 nm， the number of dangling bonds and the roughness could achieve a relatively balanced relationship， the average shear strength of the Au-Au film after bonding was 131.8 MPa， and the maximum shear strength was as high as 159.1 MPa. Therefore， the ideal surface activation treatment time of Au film surface could effectively improve the bonding quality and stability of Au-Au film， and provide theoretical guidance for the realization of low-temperature metal bonding of hybrid integrated Micro-LED devices.

The etching mechanism of Cu/Ti etchant and the change of etchant concentration was experimentally analyzed. On the basis， the changing curve of etchant concentration was clearly checked by experimental results. The control method of Cu/Ti etchant concentration was also suggested. And then， the life time and stability of Cu/Ti etchant was obvious improved，providing some reference for the research and production of related field.

. The self-developed Φ-OTDR system was used to demonstrate and verify in an offshore wind farm in Fujian Province. The state analysis and diagnosis of Marine blower unit under different working conditions such as start-up， operation and shutdown were realized， and the vibration characteristics and diagnosis basis under different working conditions were summarized. In addition， according to the monitoring and warning functions of submarine cable， such as current impact， anchor damage towing， sailing of approaching ships， etc.， the characteristics of target event perception under different state of submarine cable and surrounding environment were summarized. The measured results showed that the scheme could monitor the status of sea blower and submarine cable online， and effectively perceive the surrounding environment， which could provide a reliable technical way to improve the operation and maintenance level of offshore wind farms.

Based on the extended scalar diffraction theory （ESDT）， the theoretical model of the relationship between the microstructure height， the period width and the incidence angle of diffractive optical element（DOE）was established. The optimal design method of the structure parameters， such as design wavelength and microstructure height， was proposed based on the maximization of the bandwidth integral average diffraction efficiency （BIADE） at different incident angles. A DOE working within the near infrared waveband was taken as an example. Results indicated that when the period width was determined， the change of incident angle could cause the change of structure parameters obtained based on the maximization of BIADE. The designed method and conclusions could be used to guide the design of DOE.

With different imaging mechanisms of infrared light and visible light， the image information could not be synchronized， and the dual spectral system of infrared light and visible light could not be used simultaneously to achieve the ranging function. In this paper， the boundary of the target to be measured was used as a common feature， infrared and visible light cameras were used to collect the common features of the same target， the collected image was smoothed by the Gaussian operator， and then the Laplace expansion operator was used to detect the boundary features， linear fitting was performed on the pixel position data of the target boundary at different distances， and a ranging error model was established， so as the boundary feature matching algorithm was generated. The research results showed that the boundary feature matching algorithm could enable the infrared visible binocular system to overcome the problem of different imaging mechanisms， and achieve ranging. The ranging range could reach 40 m， and the maximum relative error is 0.975%.

In view of the increasingly high real-time requirement of target detection， a multi-target detection algorithm based on field programmable gate array was proposed. Firstly， the moving targets were extracted through the frame difference method， and then the target segmentation of images after morphological processing was performed based on the distance threshold. Finally， the moving targets were marked and displayed. The system was based on CMOS camera， FPGA， external DDR3 high-speed large-capacity cache， and realized the functions of video image acquisition， storage， target detection and display. The experimental results showed that the target detection system could effectively detect multiple targets in real time， and could reach 38 fps at a resolution of 1 024×600.

In order to improve the performance of the airborne UV alarm sensor and match the localization requirements，a UV alarm sensor based on the ICMOS architecture was designed. The working wavelength of this type of sensor covered 250～270 nm，and the alarm target information could be uploaded through the RS422 interface. It had the advantages of ultra-wide angle，high-angle resolution，high sensitivity，light weight，and low power consumption. The technical indicators，working principle and design framework of the sensor were introduced. The basic function and performance test of the sensor were completed，and it was verified by the environmental test to meet the requirements of airborne use.

The system architecture based on hybrid beam forming was studied， a new hybrid beam forming architecture was proposed， and highly integrated broadband transceiver chip AD9361 and all programmable SoC was used to build a multi-channel digital intermediate frequency system.The test results showed that the scheme was stable and reliable， and could meet the demands of large bandwidth and high speed transmission.