MULTIPATH INTERFERENCE ERROR CORRECTION IN A TIME OF FLIGHT SENSOR

A three-dimensional (3D) sensor device achieves accurate distance measurements in the presence of multipath illumination interference (MPII) by estimating the effect of indirect illumination on a given pixel's optical signal measurement and correcting the signal measurement to remove the estimated contribution from indirect illumination. After generating an initial point cloud image of a scene, the sensor device identifies target objects and background objects within the scene, where the background objects are potential sources of indirect illumination. The sensor device estimates the total amount of indirect illumination directed to a point on the target object by the background objects and received at a pixel corresponding to the point, and corrects the measured signal at the pixel to remove the contribution of this estimated indirect illumination. The sensor device performs this MPII estimation without a priori knowledge of the background objects' characteristics, and is therefore response to changes in the background.