光电导探测器的响应时间与微变等效电路  

Response time and the small signal equivalent circuit of the photoconductive detector

作　　者：江文杰[1] 施建华[1] 曾学文[1] 王省书[1] 

机构地区：[1]国防科技大学光电科学与工程学院,湖南长沙410073

出　　处：《红外与激光工程》2009年第5期792-796,共5页Infrared and Laser Engineering

基　　金：国家自然科学基金资助项目(60677041)

摘　　要：为了研究光电导探测器对高频光信号的响应特性,分析了光电导探测器响应时间的物理机理,应用解析方法推导出了它的响应时间表达式及其适用条件,建立了光电导探测器的微变等效电路模型,测试了CdSe光电导探测器在不同外接负载电阻条件下的响应时间参数。实验表明:在照度小于103lx范围内,CdSe光电导探测器的响应时间平均值为5.4ms,与外接负载电阻的阻值无关。研究表明:线性光电导探测器的响应时间由半导体材料内部的微观结构决定;探测器可等效为恒流源和光电阻的并联;外接输出电路时,其总的响应时间与探测器的响应时间和光电检测电路的时间常数两个参数有关,一般应用中可近似取为探测器的响应时间。In order to study the photoconductive detector＇s response characters to the high frequency signal, the physical mechanism of the photoconductive detector＇s response time was analyzed, the expression of the response time and its application condition were deduced, the small signal equivalent circuit was build and the response time of CdSe detector with different load resistances were measured. The experimental results show that the average response time of CdSe detector is 5.4 ms and independent of the load resistance when the optical illumination is below 10~ Ix. Based on the theoretical and experimental study, it can be concluded that the response time of the linear photoconductive detector is decided by the microstructure of the semiconductor material; a detector is equivalent to the parallel connection of a constant current supply and a photosensitive resistance; in the condition that there is a output circuit, the total response time is relative to the response time of the detector and the time constant of the circuit, commonly it is approximate to the response time of the detector.

关 键 词：光电导探测器 响应时间 恒流源 微变等效电路 光电检测电路 

分 类 号：TN710.2[电子电信—电路与系统]