Polarization encoded beam delivery and collection

Abstract

A light detection and ranging (LIDAR) apparatus includes optical source configured to emit a laser beam in a first direction, a polarization wave plate configured to transform polarization state of the laser beam headed in the first direction toward a target environment, and a reflective optical component to return a portion of the laser beam toward the optical source along a return path and through the polarization wave plate as a local oscillator signal. A polarization selective component to separate light in the return path based on the optical polarization, wherein the polarization selective component refracts orthogonally polarized light along the return path to a divergent path, wherein the polarization selective component is further configured to enable interference between the local oscillator signal and the target signal to generate a combined signal. An optical detector configured to receive the combined signal from the second direction and lensing optics configured to collimate the refracted light along a focal plane of the optical detector.