Multi-Tap Pixels: Not Only ToF

Japanese Journal ITE Transactions on Media Technology and Applications publishes an invited paper "Functional Imaging with Multi-tap CMOS Pixels" by Keiichiro Kagawa from Shizuoka University.

"Multi-tap CMOS pixels that are composed of a single photodiode, multiple sets of a charge transfer gate and storage diode, and a draining gate can implement functional imaging. In this paper, imaging systems based on the multi-tap CMOS pixel are categorized into those with synchronized active illuminations and those using coded exposure. Applications for quantitative wide-field imaging based on spatial frequency domain imaging (SFDI) using structured light projection and multi-exposure laser speckle contrast blood flow imaging (MELSCI) utilizing multiple exposure times are shown. The multi-tap CMOS pixel provides additional benefits like suppression of ambient light and motion artifact with SFDI and efficient sampling at a video rate with MELSCI."