Bayer-Pattern Image Sensor With White Pixels for Low-Light Resolution
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Image sensors face a challenge in maintaining image quality due to reduced pixel size, which leads to decreased light sensitivity and resolution, affecting the dynamic range and signal-to-noise ratio.
Innovation Solution
The implementation of a Bayer pattern-type pixel array with extended blocks and a signal processing circuitry that bins signals from specific pixel blocks to generate Bayer pattern color and illuminance information, merging these to produce a color image, thereby improving sensitivity and image quality.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If the pixel size is reduced to increase resolution, then the resolution is improved, but the light sensitivity deteriorates
Solution Approach 1:
The pixel array is divided into different pixel types (color pixels and illuminance pixels) with specialized functions. Color pixels (RGB) are segmented for color information capture while illuminance pixels (W) are segmented for brightness information capture, allowing each segment to be optimized for its specific purpose rather than requiring all pixels to be small general-purpose units
Solution Approach 2:
The patent merges color information from RGB pixels with illuminance information from W pixels through signal processing. The illuminance pixel signals are used to compensate for and enhance the color pixel signals, combining the advantages of both specialized pixel types to achieve high resolution and high sensitivity simultaneously
2Measurement precision
If the pixel size is reduced to increase resolution, then the resolution is improved, but the dynamic range deteriorates
Solution Approach 1:
The pixel array segments functionality between color pixels and illuminance pixels. Illuminance pixels with wider wavelength sensitivity capture broader light information, providing robust dynamic range data that compensates for the limited dynamic range of smaller color pixels
Solution Approach 2:
Illuminance pixel signals act as an intermediary to transfer brightness information to color pixels. The signal processing unit uses illuminance data as a mediator to enhance and compensate color pixel signals, thereby extending the effective dynamic range of the color imaging system
3Measurement precision
If the pixel size is reduced to increase resolution, then the resolution is improved, but the signal-to-noise ratio deteriorates
Solution Approach 1:
The system segments noise-critical measurements to specialized illuminance pixels that have larger effective area and better signal-to-noise characteristics. These illuminance pixels are segmented for luminance measurement where high SNR is critical, while color pixels handle chromatic information
Solution Approach 2:
The patent combines high-SNR illuminance signals with color signals in the signal processing unit. By merging the clean luminance data from illuminance pixels with color data from RGB pixels, the system achieves high resolution output with improved signal-to-noise ratio through the contribution of the higher-quality illuminance measurements
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 approach enhances the dynamic range and signal-to-noise ratio by compensating for low sensitivity in color pixels, resulting in improved image quality and sensitivity characteristics.
Implementation Method 1
each pixel included in the pixel array may include a light sensing element
Data Source
AI summary
An image sensor includes a Bayer pattern-type pixel array including a plurality of Bayer pattern-type extended blocks each having first to fourth pixel blocks, each of the first to fourth pixel blocks including first to fourth pixels, the first and fourth pixels of the first and fourth pixel blocks being configured to sense green light, the first and fourth pixels of the second and third pixel blocks being configured to sense red light and blue light, respectively, and the second and third pixels of the first to fourth pixel blocks being configured to sense white light, and a signal processing unit merging Bayer pattern color information generated from the first and fourth pixels of the first to fourth pixel blocks, and the Bayer pattern illuminance information generated from the second and third pixels of the first to fourth pixel blocks.