航天线阵CCD相机推扫成象过程的象质研究

本文从线阵CCD相机推扫成象的原理出发,根据CCD器件动态时间积分的特点,指出了它与胶片型航天相机成象的区别,推导出了沿航迹方向和穿航迹方向由光学图象向光电图象转换的调制度公式.在线性传递情况下推导了图象动态传递的MTF一般公式,并由此公式说明以往对于推扫成象的MTF计算公式仅为一般公式中的一个特例.提出了象元积分重叠率的概念,并讨论了它对整机MTF的影响.指出了线阵CCD相机在特征频率下正常成象是有一定概率的,并提出了其正常成象概率的具体算法.

IMAGE QUALITY OF CCD CAMERA PUSH-BROOM IMAGE

Based on the principles of CCD camera push-broom image & the dynamic state time features of CCD sensors, the paper deduces the along & across flight path modulation formula from optical image to photo-electric image. Under the linear transfer circumstance,the paper deduces the MTF general formula of the image dynamic state transformation,and shows that the computational formula of push-broom image was just a particular case of general formula. The paper also advances the concept of image unit integral overlapping rate and discusses its effect on the whole MTF,points out the definite probability of the normal image of CCD camera at the characteristic frequency,subsequently puts forward the concrete algorithm of its normal image probability.