IMAGING SYSTEMS WITH STACKED PHOTODIODES AND CHROMA-LUMA DE-NOISING

摘要

An imaging system may include an image sensor having pixels with stacked photodiodes in which a first photodiode generates a first image signal in response to light of a first wavelength and a second photodiode generates a second image signal in response to light of a second wavelength. The imaging system may include processing circuitry that applies a color correction matrix to isolate components of the first and second signals that are generated in response to light of the first and second wavelengths while removing components of the first and second signals that are generated in response to light of other wavelengths. The processing circuitry may increase noise correlations between the signals to mitigate noise amplification generated by the color correction matrix. The processing circuitry may apply a point filter to increase luma fidelity of the signals.

主权项

1. An imaging system comprising:
an image sensor having an array of pixels, wherein the array of pixels includes a stacked photodiode pixel having a color filter, a first photodiode, and a second photodiode, wherein the first photodiode is interposed between the color filter and the second photodiode, wherein the first photodiode generates a first image signal in response to light of a first wavelength band, wherein the second photodiode generates a second image signal in response to light of a second wavelength band that is different than the first wavelength band, and wherein the color filter blocks light of a third wavelength band that is different than the first wavelength band and the second wavelength band; and image processing circuitry that receives the first image signal and the second image signal, wherein the image processing circuitry performs a de-noising operation on at least the first image signal to generate a first de-noised image signal and performs a color correction operation on at least the first de-noised image signal, and wherein the de-noising operation is configured to reduce noise amplification by the color correction operation.