一种基于漂移扫描观测模式的星像散焦模型

漂移扫描技术虽然工作高效,但其观测模式会对成像效果造成不可避免的散焦.本文旨在通过构造模型来定量分析其散焦量,为星像质量的评估和改善提供理论参考.本文首先通过分析漂移扫描的工作机理及空间投影成像原理,建立了相应的目标星像散焦模型,并在此基础上,分别对因电荷移动速度和星像移动速度失配引起的非同步性散焦,以及空间目标曲线运动形成的轨迹投影散焦进行了定量分析.最后通过仿真实验,验证了模型的有效性,并讨论了其适用性.

A Defocus Model of Star Image Based on the Observation of Drift-scanning Mode

The technique of drift-scanning is efficient in working, but the observation of drift-scanning mode would defocus the imaging energy inevitably. The models for analyzing the value of the defocus quantificationally was built, which provides the theoretical reference for the evaluation and improvement on the image quality of spatial targets. Firstly, the principles of both drift-scanning and spatial projection imaging were analyzed. Then, the relevant spread models of targets' energy were set up, which were used to give a quantifieational analysis individually on the defocus of non-synchronization caused by the eharge's mismatch with star image in the moving velocity, and the defocus of track-projection brought by the spatial targets' curve movement. Finally, a simulated experiment was made to validate the feasibility of the relevant defocus models, whose applicability were also discussed.