折-衍混合红外激光扫描检测设备的光学系统设计

Design of Hybrid Refractive-Diffractive Optical System of Infrared Laser Scanning Testing Equipment

为了使激光扫描检测设备达到较高的检测精度并且具有较强的通用性,一般要求它的光学系统具有大视场、宽工作光谱、高成像质量的特点。以传统7片可见光波段镜头为基础,用折-衍混合单透镜代替系统中的双胶合透镜,设计了折-衍混合红外激光扫描检测设备的光学系统,主要参数为:视场60°,工作波段0.8～1.06μm,焦距30mm,后工作距离30mm。设计结果表明,在42lp/mm空间频率处的调制传递函数(MTF)值接近0.7,全视场畸变小于1.9%,重量减轻了35.3%,表明该系统像质良好且兼具小型化的特点,满足扫描检测设备的技术要求。

For the sake of laser scanning testing equipment with high testing precision and general purpose, it is required that the optical system of the testing equipment operates at wide field of view and wide spectrum with high image quality. For these purposes, based on conventional 7-element optical lens in visible band, a hybrid refractivediffractive optical system is designed for infrared laser scanning testing equipment by using a hybrid refractive- diffractive singlet instead of doublets. The main parameters of the hybrid lens are 60^o field of view, 0.8-1.06 /lm action spectrum, 30 mm effective focal length and 30 mm back working distance. The modulation transfer function （MTF） of the hybrid refractive-diffractive lens is near 0.7 at the spatial frequency of 42 lp/mm. The full field of view distortion of the lens is less than 1.9%. The weight decreases by 35.3G. The results show that with the characters of high image quality and miniaturization, the system can meet the general requirements of laser scanning testing equipment.