电子倍增CCD星相机的设计

针对导航领域对星相机的性能要求,通过在星相机中应用新型的电子倍增CCD(EMCCD),设计一种探测能力强、数据更新快的成像系统。说明了EMCCD工作原理,分析了EMCCD信噪比,介绍了基于TC285电子倍增CCD的星相机的设计方案,给出了CCD驱动电路、视频信号处理电路以及时序控制器的设计。用模拟拍星实验和实际拍星实验验证了所设计的相机的性能,同时对相机的应用进行了初步分析。通过分析实验图像的信噪比说明了设计的星相机具备在积分时间8ms以内探测6等星的能力,且其图像数据更新频率可达10frame/s,满足用短积分时间进行快速星光成像的要求。

Design of EMCCD cameras for star detection

An imaging system in a start camera with higher detection ability and faster data updata frequency was designed based on a Electron Multiplying CCD (EMCCD).To meet the performance requirements of the space navigation for star cameras,EMCCD technologies were discussed in theoretical and engineering aspects. Then,the working principle of EMCCD and its SNR were analyzed.Based on TC285 EM CCD, a design scheme for the star camera was described and the CCD driving circuit,TV signal procesing circuit and a timing controller in the camera were given.Furthermore,the camera performance was verified by simulation and experimental methods and its applications were analyzed primarily. By analyzing the experimental images, it is concluded that the camera can detect the Mv6 stars in the integration time of 8 ms,and its image data updata frequency can reach 10 frame/s. These results meet the rapid imaging requirements in short integration time.