Patent ID: 8760631
Filing Date: 2014-06-24
Classification: G01J,G01N,G01S,H01L

Abstract:
1. A method for use with a system that includes an optical sensor and that is configured to determine at least one of a distance or presence of one or more moving objects relative to the optical sensor, the method comprising: (a) driving a light emitting element with a drive signal to thereby cause a light signal to be emitted; (b) producing a sensor signal that is indicative of a portion of the light signal that reflects from one or more objects and is incident on the optical sensor; (c) performing quadrature demodulation of the sensor signal to produce in-phase (I) and quadrature phase (Q) signals; (d) determining derivatives of the in-phase (I) and quadrature-phase (Q) signals; and (e) determining a phase of the derivatives of the in-phase (I) and quadrature-phase (Q) signals.