激光辐照对红外探测器的损伤

根据红外探测器的结构特点和传热学理论，研究激光干扰机的激光器对探测器的损伤效果。以InSb探测器为例，设定入射激光从顶层辐照，结合各层之间热传导效应建立分层热模型。考虑激光在空间上的分布为高斯分布，给定初值和边界条件，利用Matlab偏微分工具箱进行建模仿真。重点研究了辐照距离、辐照时间和激光器功率等因素对探测器损伤效果的影响，给出了相应的仿真结果。当连续激光功率为50 W、距离为200 m、辐照时间为3 s时，对探测器的损伤效果主要是软损伤，受激光功率密度所限，未能造成永久性破坏。

Laser damage in IR detector

According to the structure of IR detector and the theory of thermal conduction, thermal damage of IR detector irradiated by optical maser of laser jammer was investigated. InSb photovoltaic detector was selected as a research detector. The Thermal Model was developed based on the structure of InSb detector. In this model, the detector was divided into three layers which included InSb chip, glue and copper substrate. The thermal conductivity functions of each layer were different due to various material's conduction coefficient values. The distribution in space of incident laser beam was Gaussian profile, supposing the incident laser irradiated on the top layer, and set the initial value parameters and boundary conditions. The initial temperature of the detector was 77 K and the boundary conditions were Neumann type. The multi-layer thermal models for laser damage were solved by PDE-tool. The plot of temperature rise was acquired by specifying a group of typical laser parameters through simulation. Key factors consisting of the power of optical maser, the irradiated time and the distance between the infrared detectors and optical maser were deeply researched. Through Orthogonal experimental design, a series of contrastive figures were obtained. The thermal damage effects were analyzed on basis of these data. The simulation results confirm that the detector absorbs the energy of the laser and the temperature rise centralized on InSb materials and the glue. Since the glue's conduction coefficient value is low, the glue is poor at thermal transfer, so the temperature drops dramatically in the glue layer. When the power of continuous laser is 50 W, the irradiated distance is 200 m, and the irradiated time is 3 s, the infrared detector suffers soft damage. The power of density continuous laser is lower than the pulsed laser, as a result, the optical maser doesn't bring about long-lasting destructive effects.