Design of the quadrangular prism beam splitting receiving system in the MEMS-based scanning LIDAR

Abstract

The detector bandwidth and photosensitive surface aperture are the key parameters in the high-precision and high-definition scanning 3D imaging LIDAR system, which usually require a high detector bandwidth and large photosensitive surface aperture. In order to solve the problem of a high bandwidth and small photosensitive surface of existing InGaAs detectors, this paper proposes a beam splitting method using a pair of quadrangular prisms to realize beam splitting the reception of return laser beams, which increases both the receiving field of view (FOV) and the effective photosensitive surface of the detector. The principle and structure of the prism beam splitter are discussed; a beam splitting receiving optical system with a pair of quadrangular prisms is presented, and the beam splitting effect verified by its simulation experiment is analyzed. With this novel, to the best of our knowledge, light splitting receiving method, the receiving FOV can be effectively increased to ± 5 ∘ , and the effective photosensitive surface aperture of the detector can be increased from 0.5 to 1.0 mm.