大视场高分辨率光学检查镜的设计和检测

Design and testing of optical inspection lens with large-field and high resolution

设计具有大视场、高分辨率和微小畸变特点的工业检查用光学镜头.将检查物镜的设计与照明系统相结合,利用ZEMAX光学设计软件,对照明系统和成像系统整体进行像差校正和优化设计,利用照明的匹配、明视野和暗视野的变化来改变和提高物镜的实用分辨率.设计了具有上述特点的2.35倍光学镜头,对设计好的镜头进行公差分析、外部机械结构设计,并最终完成装校.搭建调制传递函数(MTF)测试系统,对装校后的镜头进行成像质量检验,测试结果显示,实测MTF值达到理论设计值的80%以上.

The optical lens with features of large-field,high resolution and small distortion were designed for industrial inspection purpose. The inspection objective and illumination system were combined together,and the process of aberration correction and optimization were performed on the entire system by ZEMAX optical design software. By transferring the dark or bright stop in the illumination system according to the application cases,practical resolution of the objective could be slightly adjusted. Including the features described above,optical lens with the specification of 2.35 magnifying power was designed. Tolerance analysis and external mechanical design were performed based on the optical design,and the lens was finally assembled. The modulation transfer function （MTF） testing system was set up and the image quality of the assembled lens was tested on it. The results show that the tested MTF value reaches 80% of the design value.