新型高精度变焦距系统设计

Design of a High Precision Optical Zoom System

简要介绍了传统凸轮结构变焦距系统的原理、组成及存在的问题,并针对传统凸轮结构变焦距系统存在的主要问题,提出了一种新型高精度变焦距系统,用直线步进电动机替代凸轮机构控制变倍组和补偿组在直线导轨上线性或非线性精确移动,用直线光栅尺替代电位计,完成焦距值实时输出,并对步进电机实现闭环控制。该系统比传统凸轮结构变焦距系统光轴晃动减少90%,定位精度提高80%。

The principle and composition of traditional frame optical zoom systems as well as their existing problems are introduced. To solve the critical problems, a high precision optical zoom system is designed by replacing the cam system controlled zoom with a step motor and by replacing potentiometer outputted focal distance with a grating ruler. Compared with traditional frame optical zoom systems, optical axis dither is reduced by 90% and alignment accuracy increases by 80 %.