Ultrahigh Precision Cutting of Sub-micrometer Blazed Diffraction Gratings

Abstract

This paper describes a new manufacturing method that enables to obtain molds of submicrometer blazed diffraction gratings, which are difficult to be manufactured with lithography technology. The method is based on fine cutting technology using a single crystalline diamond cutting tool and a 5degree-of-freedom ultrahigh precision driving system with hydrostatic air bearing. Fine grooves, which are less than 1 micrometer pitch and asymmetric triangular shape, are fabricated by rotating diamond tool on copper and electroless nickel.