硫系玻璃在民用红外车载成像系统中的应用

针对324256非制冷探测器,设计了一个工作波段为8~12 m,有效焦距为9 mm,F数为1.3,视场角为33.2626.28的红外车载镜头。镜头采用了硫系玻璃材料Ge28Sb12Se60制备的两片镜片,结合常规红外材料锗以及硫化锌材料制备其他两片镜片,通过合理分配各个镜片的光焦度达到系统整体无热化设计的效果。利用硫系玻璃易于精密模压制备非球面的特点,仅在一片硫系玻璃镜片上设计了一处非球面。设计结果表明该系统在-40~60 ℃的温度范围内具有良好的消色差/热差性能,且调制传递函数(MTF)接近衍射极限。

Application of chalcogenide glasses in designing vehicle-mounted infrared imaging lens for civilian applications

A vehicle-mounted infrared lens was designed based on 324256 uncooled detector. The operating wavelength range of the lens is from 8 m to 12 m, the effective focal length(EFL) is 9 mm, the F number is 1.3, and the field of view(FOV) is 33.2626.28. The proposed lens was designed as a combination of two singlet lenses fabricated with the novel chalcogenide glass material Ge28Sb12Se60 and two singlet lenses fabricated with conventional infrared materials Germanium(Ge) and Zinc Sulfide(ZnS). Utilizing the differences in the thermal-optical properties of the utilized infrared materials, an athermalized optical design was realized by carefully adjusting the optical powers of the four singlets. Moreover, taking advantage of the superior property of chalcogenide glasses for molding preparation of aspherical surfaces, the imaging quality of the proposed lens could be further improved by introducing one aspherical surface on one of the chalcogenide glass singlets. The imaging quality of the proposed lens is close to the diffraction-limited system for the designed spectral range and for the temperature range from -40 to 60 ℃.