The paper proposes to use polarization imaging to detect cancer cells. For unknown reasons, the pixel is current-mode based:
Current-mode pixel schematic and peripheral readout circuitry of the imaging sensor. The pixel’s readout transistor operates in the linear mode, allowing for high linearity between incident photons on the photodiode and output current from the pixel.
The 7.4um-sized pixel in 180nm process shows excellent PRNU of less than 1% rms, in spite of Gm variations between the pixels:
|Histogram of all responses of pixels in the imaging array to a uniform|
illumination at room light intensity. The fixed pattern noise of the
current-mode imaging sensor