1 000万像素全景监控镜头的光学设计

为满足全景监控镜头的高清、大视场的要求,采用反远距系统设计了工作波段为可见的4.86~6.56μm、F数为2、垂直全视场角为185°、焦距为1.3mm的1 000万像素高清全景监控镜头光学系统。通过匹配光学材料和分配透镜光焦度,在-20~+60℃温度范围内对全景监控镜头光学系统进行了设计及像质评价。结果表明,系统在奈奎斯特频率300lp·mm-1处中心视场的光学调制传函接近衍射极限,大于0.4,0.7视场以内的光学调制传函大于0.3。系统整体无温度离焦,成像质量良好、结构紧凑,且适用于感光面尺寸为6.119mm×4.589mm、像元数为3 664×2 748的CMOS探测器。

An optical design of 10 million pixel panoramic monitor lens

In order to achieve a panoramic monitor lens of high definition and large field of view,an inverted telephoto optical system is designed.The waveband is 4.86-6.56 μm,F number is 2,vertical field of view is 185° and focal length is 1.3 mm.Especially the pixel number is 10 million,which is in a high definition level.The lens is designed for the temperature of -20-+60 ℃ by matching optical materials properly and distributing optical power of each lens-elements.The results show that the modulation transfer function of central field of view is greater than 0.4 at the Nyquist frequency of 300 lp·mm-1,which is approaching to the diffraction limit.And the modulation transfer function of 0.7 field of view is greater than 0.3.In addition,the whole system has an excellent image quality and a compact structure,which can apply to the CMOS detector of 6.119 mm × 4.589 mm pixel size and 3 664×2 748 pixel number.