Patent ID: 8854426

Claim:
A time-of-flight 3D camera for illuminating a camera field of view and capturing return image light reflected by an object in the camera field of view, comprising: a light source configured to emit source light along an optical axis of the camera; a collimator configured to receive and collimate the source light to create collimated light; a refractive diffuser that is operable to be tuned to the camera field of view and configured to receive and diffuse the collimated light to create refracted light, wherein the refracted light has a varying intensity profile that is characterized by an intensity (I) that becomes lower toward the optical axis and higher away from the optical axis, the refractive diffuser configured to guide the refracted light to illuminate only a portion of the camera field of view to reduce wasted source light, wherein the intensity (I) of the refracted light increases as an angle θ between the refracted light and the optical axis increases; and a light collector having a photosensitive surface that configured to receive the return image light to be used for calculating a distance measurement of the object.