Simple and Efficient Non-Contact Method for Measuring the Surface of a Large Aspheric Mirror

Abstract

A non-contact measurement method for measuring large aspheric surfaces with a laser tracker is proposed. Using an air-bearing probe eliminates the need to contact the optical surface and improves measurement efficiency and accuracy. Using this method, we measured the surface of an aspheric mirror 3 m in diameter and 13.6 m in the radius of curvature. The preliminary experimental result indicates that the error of surface measurement is 0.8 μm (RMS).

Keywords

• optical metrology
• laser tracker
• large-scale measurement
• non-contact measurement