Performance-controllable manufacture of optical surfaces by ultra-precision machining

Abstract

As a final evaluation specification, optical performance is important for applications of optical surfaces. However, the traditional evaluation criteria in manufacturing have been the form error and surface roughness, which are compensated to control optical performance indirectly. Previous studies have found that optical performance can differ significantly despite a similar value of form error due to different underlying error distributions. This paper, therefore, proposes a novel approach to directly achieve compensation of optical performance. Manufacturing and optical performance are linked by their primary performance parameters, machining errors and wavefront aberration, respectively. The relationship between these parameters is obtained according to an optical performance evaluation model established using optical ray tracing. The evaluation criterion for manufacturing can, therefore, be linked to wavefront aberration, which can be measured and then compensated after fabrication by an optical performance improvement model. Our experimental results demonstrate the effectiveness of the proposed method, which provides an innovative assistance to directly improve the optical performance and machining accuracy of optical mirrors.