在建立高斯型连续激光辐照InSb(PV)型探测器物理模型的基础上,采用近似解析解的形式计算了圆柱形InSb靶板的2维温度场.通过数值分析得出了在激光辐照时,InSb(PV)型探测器的温升与时间的关系,并计算出相应的损伤阈值.研究表明:在强激光连续辐照下,半导体材料InSb会发生熔融损伤,且最早发生于迎光面的光斑中心,激光的功率密度越高,造成破坏所需要的时间越短;对于一定厚度胶层的InSb(PV)型探测器,只有强度大于一定阈值的连续激光辐照才可能发生熔融损伤,越薄的胶层对应的损伤阈值越大.为了增加InSb(PV)型探测器抗激光辐照能力,应该减小胶层厚度.采用该理论计算得到不同功率下的InSb熔融时间为1.57 s和4.54 s,与实验得到的2 s和 4～5 s基本吻合.

A physical model of InSb(PV) detector irradiated by CW laser was established. The distribution of temperature was studied by Gaussian beam with 2-D thermal model. The relationship between the temperature transformation and irradiation time was obtained. By numerical method, it was found that the damage of InSb material irradiated by CW laser was melt, and it took place firstly at the center of the laser-facing surface. The higher the laser power was, the less damage time was needed. With the same laser power density, thinner sub needed less irradiation time. For a definite sub, the damage threshold of laser was higher than a certain I_min. Whereas I_min was higher for thinner sub. To improve the anti-irradiation ability, it was necessary to diminish the thickness of sub. Additionally, the calculation times of melt damage by 10.6 μm laser irradiation of different power were 1.57 s and 4.54 s, corresponding to the experimental data of 2 s and 4～5 s.