Ambient light rejection method for multiphoton coincidence detection in single-photon avalanche diode-based DToF sensors

This paper presents an adaptive control method used for multiphoton coincidence detection to reduce the effect of ambient light that exists in accessing flight time. Behavioral and statistical models are used to demonstrate the working principle with MATLAB, and the method is achieved through a compact circuit. The adaptive coincidence detection in accessing flight time achieves a higher probability of 66.5% than fixed parameter coincidence detection's 46%, while ambient light intensity is 75 klux. Additionally, it also can achieve a dynamic detection range 43.8 times higher than the fixed parameter detection. The circuit is designed in 0.11 µm complementary metal-oxide semiconductor process, and the area consumption is 0.00178mm2. The postsimulation experiment through Virtuoso shows that the histogram of coincidence detection under adaptive control circuit is consistent with the behavioral model. The proposed method acieves the coefficient of variance as 0.0495 smaller than fixed parameter coincidence's 0.0853, which means better ambient light tolerance in accessing flight time for three-dimensional imaging.