光学学报, 2012, 32 (2): 0204001, 网络出版: 2012-01-06
科学级光学CCD暗电流及机械快门时间响应特性测试
Performance Measurement of Mechanical Shutter and Dark Current for Scientific-Grade Optical CCD
光学器件 科学级电荷耦合器件 机械快门 暗电流 时间响应 optical devices scientific-grade charge coupled device mechanical shutter dark current temporal response
摘要
暗电流在科学级电荷耦合器件(CCD)长时间曝光测试实验中是主要的噪声之一。实验测试了暗电流信号平均计数随曝光时间的变化关系,并经过计算得出-10 ℃和-20 ℃下暗电流分别为2.43 ADU/(s·pixel)和0.4854 ADU/(s·pixel),同时测试了暗电流随CCD制冷温度的变化特性,结果显示暗电流随温度类似指数函数形式变化。由于CCD机械快门的时间响应特性对科学级光学CCD的短时曝光计数的影响比较大,实验测试了CCD平均计数和曝光时间的关系,得出实验所用的TEK 512 pixel×512 pixel DB CCD的机械快门在18 ms时能够完全打开。
Abstract
During the long-period exposure experiment, the dark current noise of scientific grade change coupled device (CCD) is one of the major noises, the relation of average dark current which is 2.43 ADU/(s·pixel) and 0.4854 ADU/(s·pixel) at -10 ℃ and -20 ℃ and exposure time are tested, respectively. The relation of dark current and temperature is tested. The result shows that the dark current varies with temperature exponentially. As the temporal response characteristics of mechanical shutter have a direct effect on the short time exposure of the CCD, the experiment also shows the relation of exposure time and the average counting of CCD. The result indicates that the mechanical shutter can be fully opened at 18 ms.
程书博, 张惠鸽, 刘浩, 张琛, 王哲斌, 郑志坚, 易有根. 科学级光学CCD暗电流及机械快门时间响应特性测试[J]. 光学学报, 2012, 32(2): 0204001. Cheng Shubo, Zhang Huige, Liu Hao, Zhang Chen, Wang Zhebin, Zheng Zhijian, Yi Yougen. Performance Measurement of Mechanical Shutter and Dark Current for Scientific-Grade Optical CCD[J]. Acta Optica Sinica, 2012, 32(2): 0204001.