Patent ID: 7719662
Filing Date: 2010-05-18
Classification: G01C,G01S

Abstract:
1. A method of calibrating a time-of-flight (TOF) system of the type that emits optical energy of a known phase, detects a portion of said optical energy reflected from a target object a distance Z away, and determines Z by examining phase shift in detected reflected optical energy relative to said known phase of emitted optical energy, the method comprising the following steps: (a) disposing a target object a distance Z (b) altering said known phase of said emitted optical energy by at least two known phase values; (c) for each known phase value of said emitted optical energy, determining from detected reflected optical energy a corresponding phase shift relative to said known phase; (d) using corresponding relative phase shift determined at step (c) to form an electrical model of detection characteristics of said TOF system; (e) storing data representing said electrical model; wherein data stored at step (e) is useable during run-time operation of said TOF system to provide calibrated values of Z responsive to phase shift in detected reflected optical energy.