"Though being treated as a figure of merit, there is no standard metric for measuring Parasitic Light Sensitivity in Global Shutter CMOS Image Sensors. Some measurement techniques have been presented in literature [Mey+11], though they may not apply for a general characterization of each pixel in the array. Chapter 4 presents a development of a standard metric for measuring Parasitic Light Sensitivity in Global Shutter CMOS Image Sensors that can be applied to the large variety of Global Shutter CMOS Image Sensors on the market.
The metric relies on Quantum Efficiency (QE) measurements, which are widely known in the image sensor community and well standardized. The metric allows per-pixel characterization at different wavelength and at different impinging angles, thus allowing a more complete characterization of the Parasitic Light Sensitivity in Global Shutter CMOS Image Sensors."
I have a question on the pixel process gradient if anybody can help me with an answer. For the ASIC, the process gradient can be compensated by CDS, but since the pixel is the signal source, its process gradient cannot be compensated by CDS (maybe I am wrong, but at least I don't think so). I am thinking the pixel process gradient can be compensated by the digital signal processing gain when we expose the image sensor with the same light environment and check the output from the readout circuit, then do the compensation. Please correct me if I misunderstand it.
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