Near infrared blaze metrology of silicon immersion gratings

Silicon immersion gratings offer a compact, high-resolution way to disperse the light for near-infrared spectrographs. Definitive characterization of these gratings is crucial as it enables these instruments to perform at their intended throughput. In this work, we present a procedure that precisely measures the blaze of these gratings and perform this procedure on 17 of our in-house gratings including immersion gratings manufactured for the Giant Magellan Telescope Near-Infrared Spectrograph (GMTNIRS).