Micro grinding of immersion gratings for mid-infrared spectrograph

Abstract

The purpose of this study is to develop a mid-infrared high dispersion spectrograph (IRHG) with high resolving power for astronomical observations. In this study, the authors proposed a method of grinding micro V grooves in brittle materials such as germanium using the cast iron bonded diamond grinding wheel. The wheel was sharpened using a method combining electro-discharge truing and mechanical truing employing abrasives. The grinding process was performed by the eletrolytic in-process dressing (ELID) grinding technique.