Color Filter Layout for CMOS Image Sensor Crosstalk Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In electronic devices capable of capturing color images, the presence of partition walls between color filters can lead to a decrease in sensitivity due to the suppression of incident light, causing crosstalk and affecting image quality.
Innovation Solution
A solid-state imaging element with pixels that include a first lens, a color filter with varying light absorption characteristics between its outer peripheral and inner regions, and a photoelectric conversion unit, where the inner region is formed according to the light condensing region, and may feature a light shielding film and multiple stages of light shielding walls, allowing for increased light transmittance towards the optical axis and reduced absorption.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If a partition wall is provided between color filters for each pixel, then crosstalk is suppressed, but sensitivity of the photoelectric conversion element is lowered
Solution Approach 1:
The color filter is divided into an outer peripheral part with high light absorption (for crosstalk suppression) and an inner region with high light transmittance (for sensitivity maintenance). This local differentiation allows each region to perform its specific function optimally without compromising the other
Solution Approach 2:
The color filter structure is segmented into functionally distinct regions: the outer peripheral part containing light shielding material for crosstalk suppression, and the inner region for light transmission to the photoelectric conversion element. This segmentation resolves the contradiction by assigning different properties to different spatial zones
2Object-affected harmful factors
If the outer peripheral part includes light shielding material, then crosstalk is suppressed, but light transmittance to the photoelectric conversion unit is reduced
Solution Approach 1:
Light shielding material is placed only in the outer peripheral part of the color filter where it is needed for crosstalk suppression, while the inner region maintains high light transmittance for effective light transmission to the photoelectric conversion unit
Solution Approach 2:
The color filter structure acts as an intermediary element between incident light and the photoelectric conversion unit, with the outer peripheral part blocking oblique light (crosstalk) while the inner region allows useful light transmission
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This configuration effectively suppresses crosstalk and maintains sensitivity by optimizing light absorption and transmission, enhancing image quality even with partition walls present.
Implementation Method 1
a first lens that condenses incident light
Implementation Method 2
a color filter that absorbs light having transmitted through the first lens and having a specific wavelength
Implementation Method 3
the color filter having different wavelength characteristics of light absorption between an outer peripheral part and an inner region
Implementation Method 4
a photoelectric conversion unit that photoelectrically converts the incident light having transmitted through the color filter
Implementation Method 5
a light shielding film portion that shields a part of light incident on the photoelectric conversion unit
Data Source
AI summary
Provided are a solid-state imaging element and an electronic device capable of suppressing a decrease in sensitivity even if a partition wall is provided between color filters for each pixel. A solid-state imaging element includes a plurality of pixels. Each of the plurality of pixels includes a first lens that condenses incident light, a color filter that absorbs light having transmitted through the first lens and having a specific wavelength, the color filter having different wavelength characteristics of light absorption between an outer peripheral part and an inner region of the outer peripheral part, and a photoelectric conversion unit that photoelectrically converts the incident light having transmitted through the color filter, and the inner region is formed according to a light condensing region of the incident light in the color filter.