WORKSHOP PAPER
A study on modulation transfer function and signal -to-noise ratio for Tetracell CMOS image sensors with sub-micrometer scale unit pixels
Abstract
As the unit pixel size of CMOS image sensors (CISs) decreases to sub-micrometer scale, it has become a controversial issue that an increase of resolution without enlargement of chip size leads to an improvement of image quality. In this study, we introduce a novel image simulation methodology to predict the image quality of CISs with sub-micrometer scale pixels. We predict modulation transfer function (MTF) and signal-to-noise (SNR) trends of the Tetracell CISs when the pixel size decreases from 0.8 to 0.4 μm. The MTF of the Tetracell CISs shows an improvement until the pitch of 0.45 μm. The reasons for this trend are discussed along with the degeneration of color crosstalk and SNR.Keywords
CMOS image sensors, Modulation transfer function, Signal-to-noise ratio,References
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