NON-LINEARITY CORRECTION IN PHASE-TO-DEPTH CONVERSION IN 3D TIME OF FLIGHT SYSTEMS

摘要

A time-of-flight (TOF) camera system for correcting non-linearity in phase-to-depth measurements. The TOF camera system includes a module to simulate movement of a target object by generating delays between modulation signals emitted from a transmitter and demodulation signals received by a sensor. For each delay, the TOF system calculates and stores a phase output corresponding to a simulated distance of the target object. The TOF camera may consult the stored data during normal operation to perform in-field calibration.

主权项

1. A method for calibrating measurements obtained by a time of flight (TOF) camera system, the method comprising:
emitting light from an illumination source toward a target object for a predetermined number of cycles; shifting a phase input used to modulate light emitted from the illumination source such that light emitted from the illumination source is modulated with a different phase per cycle; measuring phase differences between light emitted from the illumination source and light reflected from the target object as the phase input is shifted per cycle; and using the phase difference measurements to calibrate errors in TOF data obtained during operation of the TOF camera system.