光电成像系统的性能优化

探讨了光学系统和阵列探测器构成的光电成像系统的整体性能和优化设计问题。针对阵列探测器的不断快速更新换代,研究了如何对光学系统进行改进以优化光电成像系统的性能。从采样成像系统的取样定理出发,研究了光电成像系统的传递函数特性,讨论了采样成像系统的相位平均传递函数,分析了光电成像系统的加工与使用误差对传递函数的影响。同时,给出了光电成像系统的信噪比计算公式。文中提出用于遥感观测的大型光电成像系统的光学系统传递函数的归一化空间频率等于0.5左右可与阵列探测器的奈奎斯特频率相匹配。结果显示,如此设计可在满足信噪比的同时使传递函数在奈奎斯特频率处达到0.1左右,分辨率达到奈奎斯特频率并且不产生频谱混叠效应。

Performance optimization of electro-optical imaging systems

The whole performance of an electro-optical imaging system consisting of optical systems and array detectors was explored and optimizing design of the system was discussed. As array detectors were developed and updated in a higher speed, how to improve the optical system to optimize the whole performance of electro-optical imaging system was researched. According to the sampling theory of the sampled electro-optical imaging system, the Modulation Transfer Function(MTF) characteristics of the electro-optical imaging system were studied and the MTF phase average concept for the sampled electro-optical imaging system was discussed. Then, the effect of fabrication and use errors of the electro-optical imaging system on the MTF was analyzed and the calculation formulas of the signal-to-noise ratio of the electro-optical imaging system were given. For a remote sensing electro-optical imaging system, it suggests that the optical system MTF normalized spatial frequency should be set to be 0.5 for matching with the Nyquist frequency of the array detector. By which the system satisfies the demand of the signal-to-noise ratio, the MTF at Nyqust frequency reaches 0.1, and the resolution power is close to Nyquist frequency without the spectrum aliasing.