Design of Current-Assisted Photonic Demodulator (CAPD) for Time-of-Flight CMOS Image Sensor

This paper presents an overview of 3D real-time imaging system using electro-optical demodulator technique. The general principle to convert the phase difference between the emitted and received signals to the distance between the object and the camera is first explained, followed by the derivation of the demodulation scheme. The function of the photonic mixer device (PMD) in the scheme will be explained. In particular, the design tradeoffs of the widely popular Current-Assisted Photonic Demodulator (CAPD) will be described based on a newly developed physical model.