Study on Precision Grinding of Micro Fresnel lens dies (2nd Report)

Abstract

This paper deals with the precision grinding of micro fresnel shape with many micro grooves. Fresnel lenses are useful for the next generation type of optical devices because of its thin structure and excellent optical characteristics. In the conventional machining method, the lens materials were restricted to plastics, because the cutting tool was a single crystal diamond and the mold material was restricted to a soft metal such as copper or electroless deposited nickel–phosphorous (Ni–P) alloy. In this study, a new grinding method and a new sharp edge truing method were developed. The molds of glassy carbon for glass lenses were ground in trial