Automatic calibration technique for time of flight (TOF) transceivers

A method for use in calibrating a system that includes

• a driver configured to produce a drive signal that can be used to drive a light emitting element with the drive signal to thereby cause a light signal to be emitted,
• an optical sensor configured to produce 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, and
• circuitry configured to produce at least one of a time and phase delay measurement based on a sensor signal produced by the optical sensor, wherein the at least one of the time and phase delay measurement can be used to determine at least one of a distance and presence of one or more objects relative to the optical sensor;
• the method comprising:
• (a) during a calibration mode,
• (a.1) using the driver to produce a drive signal;
• (a.2) providing a version of the drive signal to the circuitry configured to produce the at least one of the time and phase delay measurement;
• and
• (a.3) using the circuitry configured to produce the at least one of the time and phase delay measurement to determine the at least one of the time and phase delay introduced by the system;
• and
• (b) during an operational mode, using the at least one of the time and phase delay introduced by the system, as determined during the calibration mode, to calibrate at least one of an actual time and phase delay measurement that is made by the circuitry configured to produce at least one of the time and phase delay measurement.