基于偏振技术的水下探测器光学系统设计

为了实现探测水下物体并区分材质的需求,研制了一套水下激光偏振探测设备,并设计出光学系统。偏振度是通过光学方法区分物体材质的重要参数之一,只要已知被测物体反射光的Stokes矢量,就可以求出偏振度。光学系统中共有两种方法来实现对Stokes矢量的测量:在焦面放置光电二极管直接测光强,或者放置CCD成像,通过分析图像灰度值得出光强信息。结合技术指标,在Zemax软件中运用小像差互补原理,优化设计了具有良好成像质量的光学系统。设计结果为焦距109.9mm,视场为5.2°,F数达到2.1,满足光学系统指标要求并且可以实现高精度的测量。系统仅使用5片球面透镜,结构简单紧凑,易于加工制造。将该光学设备加工出来,进行了简单的实验,证明了该光学系统的可行性。

Optical System Design for Underwater Polarization Detector

In order to detect underwater objects and to distinguish the material,a set of underwater polarization detector with the optical system was designed. The degree of polarization is one of the important parameters to distinguish the material of object by optical method. As long as the Stokes vector of the reflected light of the object which is tested is known,the degree of polarization can be calculated. There are two ways to measure the Stokes vector in the optical system:Measuring light intensity directly by the photodiode which is placed at the focal plane position,or analyzing the image gray value to know the light intensity by the CCD. Combined with the technical requirements,an optical system with good imaging quality has been optimized in Zemax software using the principle of small aberration comple-mentarity. The design results show that the focal length is 109.9mm,the field of view is 5.2°,and the F-number is 2.1,which can meet the requirements of optical system and can require high precision measurement. The system only contains 5 pieces of lens. The structure is not only simple and compact,but also easy to manufacture. The optical equipment is manufactured and we carry out simple tests to prove the feasibility of the optical system.