A high performance multi-tap CMOS lock-in pixel image sensor for biomedical applications

We have developed and evaluated the large full well capacity (FWC) for wide signal detection range and low temporal noise for high sensitivity lock-in pixel CMOS image sensor (CIS) embedded with two storage-diodes (SDs). In addition, for fast charge transfer from photodiode (PD) to SDs, a lateral electric field charge modulator (LEFM) is used for the developed lock-in pixel. As a result, the time-resolved CIS achieves a very large FWC of approximately 7000e-, low temporal random noise of 1.17e-rms at 45fps with true correlated double sampling (CDS) operation, and fast intrinsic response less than 500ps at 635nm. The proposed imager has an effective pixel array of 128(H)×256(V) and a pixel size of 11.2×11.2μm 2 . The sensor chip is fabricated by a Dongbu HiTek 1P4M 0.11μm CIS process.