Patent ID: 8878901
Filing Date: 2014-11-04
Classification: G01B,G01S,G06T,H04N

Abstract:
1. A time of flight (TOF) camera unit for an optical surveillance system, said TOF camera unit comprising: a radiation emitting unit for emitting a modulated light for illuminating a surveillance area, wherein the surveillance area is defined by a first plane and a second plane and wherein a first portion of the modulated light illuminates the first plane and a second portion of the modulated light illuminates the second plane; a radiation detecting unit for receiving the first portion and the second portion of the modulated light reflected from said surveillance area; and at least one mirror for deflecting the second portion of the modulated light onto said second plane and for deflecting the modulated light reflected from said second plane to the radiation detecting unit, wherein the radiation detecting unit includes an array of pixels configured to detect a phase shift in the modulated light reflected from each of the first plane and the second plane and wherein the radiation detecting unit is configured to generate a three-dimensional image based on a first optical path length determined from said detected phase shift in the modulated light reflected from the first plane and based on a second optical path length determined from said detected phase shift in the modulated light reflected from the second plane, wherein the second optical path length is corrected by an additional optical path length defined by a geometric position of the at least one mirror with respect to the TOF camera unit and a background of the surveillance area.