研制了一种基于单圈金属码盘的小型绝对式光电编码器,其采用低刻划密度单圈绝对式编码方式和基于线阵图像探测器的译码方式。为进一步提高测角分辨率,提出了基于金属码盘的亚像素级差值细分算法,并阐述了精码与粗码的衔接方法;使用金属码盘设计了小型绝对式光电编码器,并对其进行了测试。试制了光电编码器,在直径为38 mm的金属码盘上刻划了256条单圈绝对式码道;采用亚像素级细分实现了2048倍的角度细分。所设计的单圈绝对式光电编码器外径小于50 mm,分辨率达到2.47″。通过实验得到测角误差均方差为16.3″。该编码器的研制提高了小型光电编码器的抗震动和抗冲击性能,为特种编码器的研制提供了技术基础。

A type of photoelectric encoder using a metal code disk is developed. First, a low-density, single-ring absolute coding is proposed; then, a decoding method based on a line array image sensor is proposed. A sub-pixel D-value subdivision method based on the metal code disk is studied to further improve angular resolution, and a method for the link of fine codes and coarse codes is proposed. A small absolute photoelectric encoder using metal code disk is designed and tested. 256 single-ring absolute coding tracks are carved on the 38 mm metal disk, and the sub-pixel subdivision realizes 2048 times angular subdivision. The exterior diameter of the designed encoder is less than 50 mm, and its resolution is up to 2.47″. Experimental results show that the angular measurement error is 16.3″. The development of this encoder will enhance the resistance vibration and impact abilities of small photoelectric encoder, and will provide technical foundation for encoders of specialized use.