为了提高沙漠或海洋环境中微光夜视器件对目标探测、识别和确认的能力，进一步提高光电阴极在蓝绿光响应波段的光电发射能力，本项目拟开展蓝延伸AlGaAs光电阴极光学结构与发射机理研究。首先通过第一性原理计算不同铝组分AlGaAs材料和不同掺杂浓度GaAs材料的光学常数分布，在此基础上建立蓝延伸AlGaAs光电阴极光学性能模型和量子效率公式；然后根据理论模型研制变组分变掺杂光电阴极的光学结构设计软件，通过软件仿真研究该光电阴极光学结构的理论优化参数范围，包括GaAs发射层和AlGaAs窗口层的各子层厚度、铝组分、掺杂浓度等；最后对仿真设计的AlGaAs光电阴极结构进行材料生长和组件制备，并开展光学性能与光电发射性能的实验研究，获得具有蓝延伸波段量子效率>20%的光电阴极，同时实验结果用于验证或修正理论模型。该项目将为提高蓝延伸光电阴极的光电发射性能及完善制备提供理论指导和实验依据。

The ability of detection, recognition and identification of targets in the desert terrain or marine environment is to be strengthened, therefore, the photoemission performance of photocathodes responding in the blue-green waveband region should be improved. In this project, we will investigate the optical structure and photoemission performances of blue-extended AlGaAs photocathode. Firstly, optical constants of AlGaAs materials with different Al components and GaAs materials with different doping concentrations will be calculated by the first principle. Based on the results, a theoretical reasonable optical property model and quantum efficiency formula of blue-extended AlGaAs photocathode will be established. Then the designing software for the optical structure of the photocathode with varied components and concentrations will be developed with the basis of the theory model. And the optimized optical structure of the photocathode will be simulated in theory, including the thickness, component and doping concentration etc of the sub layers in the GaAs active layer and the AlGaAs window layer. Lastly, material grown and module preparation will be proceed for the designed AlGaAs photocathode, and then optical property and photoemission performance will be measured by the experiments. The blue-extended photocathode will be obtained with superior photoemission performance (quantum efficiency >20%) in the blue-green waveband region. At the same time, the experimental results are used to verify or correct theoretical model. Based on the above research results, we will provide theoretical guidance and experimental basis for improving the photoemission performance and preparation of the blue-extended photocathode.