论文部分内容阅读
一种编码掩模红外成像系统的建模方法,模型由两个功能部分组成:编码掩模和理想透镜组成的成像部分以及实际透镜的非理想成像部分.其中,第一部分可表达为掩模按照掩模到镜头前平面的距离发生菲涅尔衍射的作用,第二部分可表达为平行光照射光瞳结构并按照同样的距离发生菲涅尔衍射后的聚焦结果.因此,编码掩模成像系统的点扩散函数PSF可以由编码掩模的衍射模式和实际透镜的PSF组成.根据编码掩模的评价函数以及系统PSF的估计,研究发现,基于Dammann光栅结构的编码掩模模式对于直接成像和图像恢复重建具有比较均衡的性能.实验结果表明,对于直接成像的编码掩模成像系统,其掩模应该具有较强的随机性,而对于图像重建系统需具有较多的周期性结构.
A method for modeling a coded mask infrared imaging system consists of two functional parts: an imaging part consisting of an encoded mask and an ideal lens, and a non-ideal imaging part of an actual lens, wherein the first part can be expressed as a mask according to The Fresnel diffraction effect occurs at a distance from the mask to the anterior plane of the lens, and the second part can be expressed as a parallel light-illuminated pupil structure and the Fresnel diffraction focusing result at the same distance is obtained. The point spread function PSF can be composed of the diffraction pattern of the coding mask and the actual lens PSF.According to the estimation function of the coding mask and the estimation of the PSF of the system, it is found that the coding mask mode based on the Dammann grating structure is not suitable for direct imaging and image restoration Reconstruction has more balanced performance.The experimental results show that the mask should have strong randomness for the direct imaging coding mask imaging system and has more periodic structure for the image reconstruction system.