基于面阵探测器的绝对轴角编码器的细分技术  

Subdivision technique of absolute angular encoder using array detector

作　　者：王英男[1] 袁波[1] 倪旭翔[1] 

机构地区：[1]浙江大学现代光学仪器重点实验室国家光学仪器工程技术研究中心,浙江杭州310027

出　　处：《浙江大学学报（工学版）》2011年第2期370-374,共5页Journal of Zhejiang University：Engineering Science

基　　金：浙江省自然科学基金(Y1090391);中央高校基本科研业务费专项资金资助项目(2009QNA5009)

摘　　要：为了解决码盘尺寸和分辨率之间的矛盾,提出一种基于面阵探测器的绝对式轴角编码及细分技术。该细分技术能够在不改变码盘现有编码方式的基础上提高编码器的分辨率,并且有利于码盘的安装和调节.码盘经过准直光束照明之后经过成像物镜放大,经光学放大后的码盘图像被面阵光电探测器接收,然后分别利用图像处理技术读取粗码和利用探测器像素的空间均匀性进行细分,得到由粗码和精码共同构成的角度信息.根据编码原理组建编码器系统并通过实验验证该细分技术的可行性.此外,对影响角度测量准确度的一些因素也进行了分析,分析表明,光照和对焦是2个影响测量的主要因素.实验中,系统可以将角分辨率由13位提高到18位.To solve the contradiction between the size and resolution,a new subdivision technique based on array detector are proposed for absolute angular encoder.The proposed technique can well improve the angular resolution without changing the coded disc and is convenient for installing and adjusting.The coded disk is firstly lighted by the collimated beam and then magnified by the image lens.The magnified image of coded disc is finally received by the detector.Then the binary code is obtained by image processing and the minimum code unit is subdivided by the detector＇s pixels,respectively,which are both contributed to the angular position.The encoder system was set up according to the proposed coding principle and the feasibility of subdivision technique was experimentally testified.Additionally,some factors to influence the angular measurement precision were also analyzed,the result proved that the illumination and focus are two main influential factors.The angel resolution can be improved from 13 bit to 18 bit in the experiment.

关 键 词：绝对式轴角编码器 成像式 图像处理 细分 

分 类 号：TH741.2[机械工程—光学工程]