科学级CCD相机在星敏感器中的设计与应用

星敏感器通过探测天球上不同位置的恒星来确定航天器的姿态.星相机是星敏感器的成像系统.虽然近年来CMOS成像技术快速发展,但在科学级成像领域,特别是星敏感器应用中,CCD技术较成熟.本文的研究目的是研究一种探测能力强、数据更新快的用于星敏感器的成像系统.文中主要研究了基于TH7888A科学级CCD传感器的星相机的设计和应用,说明了CCD工作原理,详细分析了该种CCD传感器的星等探测灵敏度,论述了CCD星相机的设计方案.并用成像实验、动态范围测试、星等探测能力实验等实验验证了所设计的相机的性能.设计的星相机可以用给定的小型光学系统在60 ms以内的积分时间探测6等星,相机可达到10帧／秒的图像数据更新频率,满足短积分时间进行快速星光成像的要求.

Design and Application of Scientific CCD Camera for Star Sensor

The star sensor is a high-precision attitude sensitive measuring instruments, which determine spacecraft attitude by detecting different positions on the celestial sphere. Star camera is the imaging system of star sensor. Despite the rapid development of CMOS technology, in science class imaging, especially, CCD camera still has a great advantage in applications of star sensor. The purpose of this study is to increase the performance and data update frequency of CCD camera for star sensor. The working principle of CCD is described, the CCD sensor detection sensitivity is analyzed, and the design of CCD star camera is discussed based on TH7888A. Performance of the camera can be validated through imaging and detection experiments. By analyzing the experimental images, it is found that the camera can detect Mv6 stars in 60 ms integration time through a given the small optical system. The camera’s image data update frequency can reach 10 frame/s and meets the rapid imaging requirements in short integration time.