为了降低飞行器侧摆及前后摆对TDICCD空间相机成像质量的影响,提出了对飞行器侧摆角和前后摆角范围及控制误差的要求,以获取高信噪比和高分辨力图像。根据TDICCD空间相机像移产生机理,给出了侧摆和前后摆引起的像移及像移计算参数的数学公式。应用调制传递函数(MTF)作为图像质量的评价依据,确定了满足空间相机成像质量要求的侧摆角和前后摆角范围,分析了飞行器侧摆和前后摆对地面像元分辨力的影响。计算得出,相机成像过程中,当侧摆角和前后摆角的控制误差为0.1°,且侧摆角和前后摆角的视轴角不大于4.8°;或当侧摆角和前后摆角的控制误差为0.05°,侧摆角和前后摆角的视轴角不大于9.5°时,可满足积分级数96级,MTF不小于0.95的要求。实验结果表明,该方法简单,易于实现,适用于TDICCD空间相机成像质量的研究。

In order to reduce the influence of scroll and pitch movements on the image quality of a TDICCD space camera,the requirements for the scopes of scroll angle and pitch angle and their control errors are put forward to obtain an image with high signal noise ratios and high resolution. According to the mechanism of camera image motion,the image motion caused by the scroll and pitch of aerocraft and the formula for calculating the image motion are given. The image quality is evaluated by the Modulation Transform Function(MTF),and the scopes of scroll angle and pitch angle that can meet the requirements of the space camera image quality are determined. Furthermore,the influence of the scroll angle and pitch angle on the ground pixel resolution is analyzed. From calculations,it is concluded that,when the control error of scroll angle and pitch angle is 0.1° during the imaging and the angle of axis of sight caused by the scroll angle and pitch angle is no more than 4.8°;or the control error of scroll angle and pitch angle is 0.05° and the angle of axis of sight is no more than 9.5°,the requirements of the integration progression is 96 and the MTF is no less than 0.95 can be met. The experimental results indicate that the proposed method is simple and easy to implement,which is suitable for the research on image quality of the TDICCD space camera.