基于相对运动的脉冲激光辐照探测器热效应数值分析  

Numerical Analysis of Thermal Effect of the Detector Irradiated by Pulsed Laser Based on Relative Motion

作　　者：任晓东 雷武虎 曾凌清 王勇[1] REN Xiao-dong;LEI Wu-hu;ZENG Ling-qing;WANG Yong(School of Electronic Countermeasures,National University of Defense Technology,Hefei 230037,China;The Troops of 32026,Urumqi 841700,China)

机构地区：[1]国防科技大学电子对抗学院 [2]32026部队

出　　处：《光子学报》2019年第1期99-105,共7页Acta Photonica Sinica

基　　金：国家自然科学基金(No.6167154);脉冲功率激光技术国家重点实验室基金(No.SKL2017ZR02)~~

摘　　要：基于热传导理论,构建了相对运动情况下脉冲激光辐照HgCdTe探测器的理论模型,利用有限元法分析比较了不同重频、不同移动速度下探测器的热效应.结果表明,在相对静止情况下,重频脉冲激光辐照HgCdTe探测器时,激光能量主要被HgCdTe光敏层吸收,温度场高温区主要分布在HgCdTe层与CdZnTe层交界面附近;重频为1kHz、10kHz时几乎没有温度累积效应,当重频为100kHz时,随着脉冲数的增多,峰值温度不断增加,有明显的温度累积效应.在相对运动情况下,随着激光光斑的移动,温度峰值所在的位置逐渐向速度矢量方向偏移.从损伤的角度考虑,当每个温度峰值都大于HgCdTe熔融温度时便能达到损伤的空间区域累积效应,实现对多个探测像元的损伤.定性分析了汇聚到探测器焦平面单脉冲激光光斑在不同移动速度下的热效应,结果表明移动速度越快,脉冲结束时刻峰值温度越低,温升曲线的斜率越小,上升越慢.Based on the theory of heat conduction,a theoretical model of HgCdTe detector irradiated by pulsed laser in relative motion is established.The thermal effects of the detector at different repetition frequencies and moving speeds are analyzed and compared by finite element method.The results show that the energy of the laser is mainly absorbed by the HgCdTe photosensitive layer and the high temperature field is mainly distributed near the interface between the HgCdTe layer and the CdZnTe layer when the HgCdTe detector is irradiated by a repetitive frequency pulse laser under the relative static condition.There is almost no temperature accumulation effect when the frequency is1kHz and10kHz.While when the frequency is100kHz,the peak temperature increases with the increase of the number of pulses,and there is an obvious temperature accumulation effect.The position of the peak temperature shift gradually to the direction of the velocity vector with the movement of the laser spot under the relative motion.From the point of view of damage,the cumulative effect of the damage in the space area can be achieved when each temperature peak is larger than the melting temperature of HgCdTe,and as a result,the damage to multiple detection pixels can be achieved.The thermal effect of the detector irradiated by monopulse laser spot at different moving speeds is analyzed.The faster the laser spot moves,the lower the peak temperature is at the end of the pulse,the smaller of the slope of the temperature rise curve and the slower of the temperature rise.

关 键 词：脉冲激光 HGCDTE探测器 有限元 相对运动 温度场 损伤 

分 类 号：O436[机械工程—光学工程]