Aptina's patent applications US20120274744 and EP2519001 "Structured light imaging system" by Chung Chyn Wan, Xiangli Li and Gennadiy Agranov proposes background light extraction in stuctured light system with pulsed light source:
The signal plus background and background are stored on the different caps in the pixel...
...and then read out for further processing:
The signal plus background and background are stored on the different caps in the pixel...
...and then read out for further processing: