Abstract: An optical proximity sensor system to detect a distance to a target object is provided. The optical proximity sensor system includes a laser that generates an emitted optical beam at a linear polarization and an optical cavity system that includes an optical cavity defined by a distance between the laser and the target object. The target object reflects the emitted optical beam to generate a reflected optical beam. A partially reflective mirror diverts a portion of the emitted optical beam and/or the reflected optical beam. A photodetector receives the diverted optical beam and generates a proximity signal that has a frequency that is indicative of the distance to the target object based on the diverted portion of the at least one of the emitted optical beam and the reflected optical beam. A proximity processor calculates the distance to the target object based on the frequency of the proximity signal.