Color filter array and image sensor

Abstract

The invention relates to a color filter array and an image sensor. Embodiments are described of a color filter array including a plurality of tiled minimal repeating units. Each minimal repeating unit includes an invisible-wavelength filter layer including a plurality of filters and a visible-wavelength filter layer positioned on the invisible-wavelength filter layer and having a plurality of filters such that each filter from the visible-wavelength layer is optically coupled to a corresponding filter in the invisible-wavelength layer.

Description

technical field [0001] The disclosed embodiments relate generally to image sensors, and particularly, but not exclusively, to image sensors that include multilayer color filter arrays (CFAs). Background technique [0002] The image sensor can be coupled with an invisible wavelength filter so that it can capture images at wavelengths outside the visible wavelength range, such as in the infrared (IR) wavelength range. Two materials are used to make existing infrared filters: pigment-based materials and C-based materials. Pigment-based IR filters are typically used in image sensors with pixel sizes smaller than 1.4 μm. It has high infrared transmission which translates to a higher signal-to-noise ratio (SNR), but it cannot completely block visible wavelengths such as blue and red, so it produces worse color errors. C-based IR filters are typically used in image sensors with pixel sizes greater than 1.4 μm. It completely blocks visible wavelengths like blue and red, and thus ...

AI Technical Summary

Problems solved by technology

It completely blocks visible wavelengths like blue and red, and thus has less color error, but it has low IR transmission which translates to lower SNR

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