小F数红外光学系统设计  

Design of Small F-number Infrared Optical System

作　　者：关禹聪 胡源[1] 刘子龙 周新雨 GUAN Yucong;HU Yuan;LIU Zilong;ZHOU Xinyu(School of Optoelectronic Engineering,Changchun University of Science and Technology,Changchun 130022,China)

机构地区：[1]长春理工大学光电工程学院,吉林长春130022

出　　处：《红外技术》2024年第12期1433-1439,共7页Infrared Technology

摘　　要：红外探测器不断朝着高分辨率、小像元的方向发展。要想实现小像元的探测,那就要求红外光学系统要具有更小的F数。所以本文基于对小像元探测的需求,通过采用库克型离轴三反结构,设计出了一款F数接近1的离轴三反红外光学系统。该光学系统的主镜、次镜、三镜均采用偶次非球面,F数为1.3,焦距为60 mm,视场角为1.6°×2.4°,波段为1.1~2.5μm。该设计的红外光学系统在空间截止频率100线对每毫米处调制传递函数(MTF)都大于0.6,并且弥散斑RMS值远小于探测器的像元尺寸,畸变小于2%,系统设计以及仿真后的结果说明,系统各视场的MTF均接近衍射极限,满足成像质量要求,能够实现小像元探测的需求。Infrared detectors are being developed for high resolution and small pixels.To detect small pixels,an infrared optical system must have a small F-number.Therefore,based on the demand for small-pixel detection,this study designed an off-axis three-reflection infrared optical system with an F-number close to 1 using a Cook-type off-axis three-reflection structure.The primary,secondary,and tertiary mirrors of this optical system were all aspherical,with an F-number of 1.3,focal length of 60 mm,field of view of 1.6°×2.4°,and a wavelength band of 1.1-2.5mm.The modulation transfer function(MTF)of this infrared optical system design was greater than 0.6 at a spatial cutoff frequency of 100 line pairs per millimeter.The RMS value of the diffuse spot was smaller than the pixel size of the detector,with a distortion of less than 2%.The system design and simulation results indicated that the MTF of each field of view was close to the diffraction limit,meeting both imaging quality and small-pixel detection requirements.

关 键 词：小F数 离轴三反 非球面 光学设计 

分 类 号：TN216[电子电信—物理电子学]