Design of an optical illumination system for a long wave infrared scene projector based on diffraction characteristics

Abstract

This study proposes an optical illumination system design based on vector diffraction characteristics and the Scheimpflug principle to determine an optimal relationship between illumination uniformity, energy utilization, and system size in an infrared scene projector. We investigate the influence of digital micromirror device (DMD) diffraction efficiency at different incidence angles on energy utilization rate and establish a two-dimensional diffraction grating model to determine the optimal incidence angle of the DMD beam. We demonstrate that the optical illumination system of a long-wave infrared (LWIR) scene projector based on diffraction characteristics can simulate an infrared scene with a compact structure, high energy efficiency, and high uniformity.