19 February 2013 A 3D image sensor with adaptable charge subtraction scheme for background light suppression
Author Affiliations +
We present a 3D ToF (Time-of-Flight) image sensor with adaptive charge subtraction scheme for background light suppression. The proposed sensor can alternately capture high resolution color image and high quality depth map in each frame. In depth-mode, the sensor requires enough integration time for accurate depth acquisition, but saturation will occur in high background light illumination. We propose to divide the integration time into N sub-integration times adaptively. In each sub-integration time, our sensor captures an image without saturation and subtracts the charge to prevent the pixel from the saturation. In addition, the subtraction results are cumulated N times obtaining a final result image without background illumination at full integration time. Experimental results with our own ToF sensor show high background suppression performance. We also propose in-pixel storage and column-level subtraction circuit for chiplevel implementation of the proposed method. We believe the proposed scheme will enable 3D sensors to be used in out-door environment.
© (2013) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Jungsoon Shin, Jungsoon Shin, Byongmin Kang, Byongmin Kang, Keechang Lee, Keechang Lee, James D. K. Kim, James D. K. Kim, "A 3D image sensor with adaptable charge subtraction scheme for background light suppression", Proc. SPIE 8659, Sensors, Cameras, and Systems for Industrial and Scientific Applications XIV, 865907 (19 February 2013); doi: 10.1117/12.2005761; https://doi.org/10.1117/12.2005761

Back to Top