Correction of depth images from t-o-f 3d camera with electronic-rolling-shutter for light modulation changes taking place during light integration

Abstract

In embodiments, a T-O-F depth imaging device renders a depth image of an object that has corrected depth values. The device includes a pixel array that uses an Electronic Rolling Shutter scheme. The device also includes a light source that transmits towards the object light that is modulated at an operating frequency, and an optical shutter that opens and closes at the operating frequency. The optical shutter further modulates the light that is reflected from the object, before it reaches the pixel array. The transmission of the light and the operation of the shutter change phase relative to each other while at least one of the pixels is sensing the light it receives, which permits a faster frame rate. Depth is determined by the amount of light sensed by the pixels, and a correction is computed to compensate for the changing phase.