A Deblurring Method for Indirect Time-of-Flight Depth Sensor

Indirect time-of-flight (iToF) depth sensors can obtain depth from the phase offset between emitted and received modulated infrared (IR) pulsed light. However, these sensors suffer from motion blur artifacts when there are moving objects in the scene causing depth measurement distortion. By analyzing the mechanism of motion blur, this article summarizes motion blur into categories: half-frame motion blur and full-frame motion blur. For both blur categories, this article, respectively, proposes the deblurring method based on charge correction with the adjacent frame charge reference and the neighborhood similar charge reference. Based on the range resolution equation, the proposed pixel-based blur detection method can adaptively detect motion blur. For detected blurred pixels, the proposed deblurring method removes blur by recalculating the depth of blurred pixels. Motion blur was suppressed at 30 frames/s owing to the proposed deblurring method. The depth error is about 1.68% over the range of 1-2 m, with a modulation frequency of 40 MHz. Experimental results demonstrate that the proposed deblurring method can effectively eliminate the motion blur of moving objects with minimal computational cost.