长波红外平面计算衍射光学系统设计  

Design of Long-Wave Infrared Planar Computational Diffraction Optical System

作　　者：王喆 盛忠 韩璟圳 甄政 张承然 马德超 朴明旭[1] Wang Zhe;Sheng Zhong;Han Jingzhen;Zhen Zheng;Zhang Chengran;Ma Dechao;Piao Mingxu(School of Optoelectronic Engineering,Changchun University of Science and Technology,Changchun 130022,Jilin,China;Beijing Institute of Remote Sensing Equipment,Beijing 100854,China)

机构地区：[1]长春理工大学光电工程学院,吉林长春130022 [2]北京遥感设备研究所,北京100854

出　　处：《光学学报》2024年第14期202-209,共8页Acta Optica Sinica

基　　金：国家自然科学基金(62105041)。

摘　　要：提出一种平面计算衍射光学系统,分析平面衍射光学系统的像差特性,基于波前像差理论并利用Zernike多项式构建波前像差模型,通过傅里叶变换建立点扩散函数模型,结合反卷积算法处理图像,消除了轴外像差对成像的影响。设计一种波段为8~12μm、焦距为12 mm、F数为1.2的平面衍射光学系统,利用计算成像的方法将视场从1°扩大到4°,物距为4 m到无限远。结果表明,该方法效果明显,成像质量得到提升,实现了光学系统的小型化和轻量化,为光学系统的集成化提供了新思路。Objective Traditional infrared optical systems are typically bulky and comprise numerous lenses. To achieve miniaturization, planar imaging elements with microstructured surfaces are often employed. However, these complex surfaces can pose processing challenges and increase costs. This study introduces a planar diffractive element that integrates Fresnel and diffractive surfaces to address the aforementioned issues. Diffractive optical elements possess unique dispersion and temperature characteristics. By combining a diffractive surface with a Fresnel surface, the optical system's structure can be simplified, reducing its weight and achieving performance indices that are difficult for traditional systems to match. This approach is characterized by ease of processing and low cost. Increasing the field of view exacerbates offaxis aberrations, leading to diminished image quality. Analysis of these aberrations indicates that coma and field curvature are the primary monochromatic aberrations affecting Fresnel and diffractive surfaces. To address this, we propose a design method incorporating computational imaging to correct off-axis aberrations in planar diffractive elements, even as the field of view expands.Methods The formulas for monochromatic aberration in Fresnel and diffractive surfaces have been derived. Coma and field curvature become the primary monochromatic aberrations as the field of view increases. Therefore, correcting off-axis aberrations in optical design focuses on astigmatism, while coma and field curvature are addressed in the computational imaging phase. The imaging process in the optical system is essentially one of image degradation. The final image is obtained by passing a clear image through the optical system, convolving it with the point spread function(PSF), and adding noise. Thus, the PSF can be used as a restoration function to deconvolve the imaged image and obtain a clear image. A wavefront aberration model of the optical system is established using Zernike polynomial fitting. A PSF mod

关 键 词：光学设计 计算成像 衍射元件 点扩散函数 空间变化反卷积 

分 类 号：O436[机械工程—光学工程]