基于6次反射环形孔径透镜的微光学标签系统

Micro-Optics Label System Based on Six-Reflection Fold Annular Aperture Lens

介绍了一种微光学标签系统,结合理论分析提出用大孔径长焦距的透镜作为接收端可以提升系统的成像性能。利用Zemax光学软件设计出一种大孔径长焦距的6次反射环形孔径超薄透镜,该透镜前表面为平面反射镜,后表面为4个同轴环形非球面反射镜,外直径为28mm,有效焦距为38mm,镜头厚度为5mm。在保证与4次反射透镜通光孔径一致的条件下,通过改进透镜结构增加了反射次数,减小了厚度,扩展了焦距。对基于环形孔径超薄透镜为接收端的微光学标签系统进行了整体优化分析,并给出了模拟成像图的对比,结果发现使用6次反射透镜做接收端可以增加系统的接收距离,减小接收图像的畸变。最后利用同态滤波的处理方法,有效地校正了亮度不均匀的接收图像。

A special micro-optics label system is introduced. A large aperture and long focal length lens structure, which is used as the system receiving terminal, is demonstrated to be able to improve the imaging performance significantly by theoretical analysis. A six-reflection fold annular aperture ultra-thin lens with large aperture and long focal length is designed with the aid of optical engineering software Zemax. The front surface is a plane mirror and the rear surface consists of four concentric annular aspheric reflectors. The outer diameter of the lens is 28 mm, the effective focal length is 38 mm, and the thickness of the lens is 5 mm. With the clear aperture consistency of a four-reflection fold annular aperture lens, the structure of the equipment is improved to increase the number of reflections, effectively reduce the thickness of the lens, and enlarge the focal length of lens. In this work, an optimized design and analysis to the micro-optics label system are reported. It is based on the annular aperture ultra- thin lens as receiving terminal. And the comparison of simulation imaging is given. The results show that using six- reflection fold annular aperture lens as receiving terminal can increase the receiving distance and reduce the distortion of simulated images. Finally, a received image with non-uniform brightness is effectively corrected by using homomorphic filtering method.