Synaptics Incorporated
Derivation of depth information from time-of-flight (TOF) sensor data

Abstract:

A time-of-flight sensor includes a light source to transmit periodic bursts light in a direction of one or more objects and an array of optical sensing elements to detect light reflected from the one or more objects and generate sensor data corresponding to the detected light. A distance calculator determines depth information of the one or more objects by determining a general phase shift of the reflected light relative to the transmitted light based on a first frame of the sensor data and a second frame of the sensor data, calculating an incremental phase shift of the reflected light relative to the transmitted light based on a linear relationship between the first frame and the second frame in relation to the general phase shift, and combining the general phase shift with the incremental phase shift to determine an actual phase shift of the reflected light relative to the transmitted light.