摘要
精细导星仪(FGS)是空间天文望远镜精密稳像系统高精度姿态信息的快速检测装置,CMOS图像传感器的成像效果直接影响精细导星仪姿态信息的解算精度。而实际工作时,CMOS成像器件存在最佳的读出范围,超出此范围的入射光强与光生电子数的线性度低,无法获取有效星点来满足后级的质心坐标解算。为解决这一问题,提出一种估算不同星等最佳积分时间的方法,并将积分时间作为探测器参数选择与调整的主要依据。测量结果表明,像元暗电流的读出码值和探测器面阵RMS噪声值均随积分时间的增加而增加。依据星点光斑分布模型给出常用星等的最佳积分时间范围,结合星点的分布情况,得出7等星在视场范围内的星数约为7颗,论证了小型CMOS器件对星斑的探测能力。
Fine guidance sensor(FGS)in the space astronomical telescope can realize highprecision measurement of attitude information for the precision image stabilization system.The imaging effect of the CMOS image sensor(CIS)directly affects the calculation accuracy of FGS.However,the CMOS imaging device has the best readout range in actual operation,and the linearity of the incident ray intensity and the number of photo-generated electrons beyond this range is low,and the effective star points cannot be obtained to meet the centroid coordinate solution of the later stage.In order to solve this problem,a method for estimating the best integration time of different magnitude is proposed and the integration time can be used as the main basis for the selection and adjustment of detector parameters.The measurement results show that both the dark current of the sensor and the RMS noise will increase with the increasing integration time.According to the star facula distribution model,the best integration time range of commonly used stars is calculated.Combining with the star spot distribution,it is concluded that there are about seven stars in the field of view of 7-magnitude stars,which demonstrates the detection ability of small CMOS devices for star spots.
作者
王佳怡
房陈岩
尹达一
WANG Jiayi;FANG Chenyan;YIN Dayi(Shanghai Institute of Technical Physics of the Chinese Academy of Sciences,Shanghai 200083,CHN;Key Lab.of Infrared System Detection and Imaging Technol.of the Chinese Academy of Sciences,Shanghai 200083,CHN;University of Chinese Academy of Sciences,Beijing 100049,CHN)
出处
《半导体光电》
CAS
北大核心
2021年第5期721-725,732,共6页
Semiconductor Optoelectronics
