侧摆成像下多片TDICCD拼接相机分段异速研究

针对多片TDICCD拼接相机,为提高其在侧摆成像时的成像质量,减少系统设计难度,提出了不同成像加载参数时的行频调整模式。推导出相机侧摆时拼接TDICCD各像元的行频求解公式,建立侧摆角度与行频的关系式。以调制传递函数（MTF）作为评价相机成像质量的指标,详细分析在侧摆成像时对不同积分级数的分段异速调整方式。结果表明,侧摆成像时为满足系统对传递函数下降不超过5%的要求,侧摆角度越大,积分级数越高,行频调整越复杂,反之越简单。在积分级数不超过64级、侧摆角度不超过40°时,工作方式可以简化为按照相邻两片TDICCD同一行频工作,该结论对实际工程应用和设计具有指导作用。

Research on Subsection Image Motion Mismatching for Multi-TDICCD Mosaic Camera of Scroll Imaging

In order to improve the image quality of the multi-TDICCD mosaic camera at scroll imaging and reduce the design difficulty,the adjusting pattern of row frequency is proposed according to different loading parameters.The expression of the row frequency of every pixel is deduced when the mosaic TDICCD is scroll imaging.Relationship between scroll angle and row frequency is established.On the basis of this,MTF is used to evaluate the image quality in this paper.The adjusting pattern of subsection motion mismatching due to number of stages at scroll imaging working mode is analyzed in detail.The results show that,in order to fulfill the descending of MTF less than 5% which meeting the need of the system,the bigger the scroll angle and the integral number of the TDICCD are,the more complex the adjusting pattern of row frequency is.Contrarily,the easier the adjusting pattern of row frequency is.When the integral number of the camera is not more than 64,the scroll angle is not more than 40°,the working pattern can be simplified to every two pieces TDICCD work at the same row frequency.The conclusion will be useful to engineering application and designing reference.