双光束补偿扫描系统

System of scanning by Dual-laser beam Compensation

提出一种新的高精度大型平面扫描仪。利用双光束补偿系统，扫描头由一特殊光路组成。当入射光通过此光路后，产生对称输出的两束光。当入射光发生角漂或扫描头发生摆动时，输出的两束光对称上下漂移，其中心线保持不变，故扫描形成的基准面保持不变，从而大大提高了测量精度。经实验证明，测量精度优于2．5×10－6。

This paper is a new scanning method for flatness measurement for large plates. It's anew compensation method by dual-laser beam datum plane generation optical set-up. In the unit, theincident 1aser beam is split into two and the two beams have such a symmetric property. In case any orboth of the following occur: incident laser beam is unstable or optical set^up is fluetuation. Thissymmetrical property will ensure a stable central line and therefore a stable central line and there fore adatum plane. The measurening precision is 2. 5 × 1O-6