Stacked CMOS Image Sensor With Polarizing Mask for Synchronized Light Capture
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In low-lighting applications, CMOS image sensors using separate devices for unpolarized visible and near-infrared light waves face synchronization issues, leading to inaccurate image representation due to timing offsets, which increases computing resources needed for image processing.
Innovation Solution
A CMOS image sensor design with a first array of photodiodes stacked over a second array, featuring a polarization structure and filter structure that multiplexes unpolarized and polarized visible and near-infrared light waves, allowing simultaneous capture of polarized and unpolarized light waves, thereby improving image processing accuracy and reducing resource requirements.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If separate devices are used for capturing unpolarized visible and near-infrared light waves, then the capture of different light waves is possible, but synchronization issues occur leading to timing offsets and inaccurate image representation
Solution Approach 1:
The patent combines multiple photodiode types (first photodiodes for unpolarized visible light, second photodiodes for polarized visible light, and third photodiodes for near-infrared light) into a single stacked array structure. This merging eliminates the need for separate devices, thereby resolving synchronization issues and timing offsets while maintaining the ability to capture different light waves simultaneously.
Solution Approach 2:
The patent introduces a vertical stacking dimension to arrange different photodiode arrays at different depths within the same device. This three-dimensional arrangement allows simultaneous capture of multiple light wave types without requiring separate horizontal devices, thereby achieving both versatility and synchronization.
2Adaptability or versatility
If separate devices are used for unpolarized and polarized light wave capture, then diverse light wave detection is achieved, but timing offsets increase computational resource requirements
Solution Approach 1:
By merging all light wave detection functions into a single stacked photodiode array, the patent eliminates timing offsets that would otherwise require complex computational correction. This reduces the computational resources and energy needed for image processing while maintaining diverse light wave detection capabilities.
3Adaptability or versatility
If multiple separate devices are deployed for comprehensive light wave capture, then all light wave types can be detected, but device complexity and manufacturing resources increase
Solution Approach 1:
The patent merges multiple detection functions into a single integrated device with stacked photodiode arrays, dramatically reducing system complexity and the number of components required while maintaining comprehensive light wave detection coverage.
Solution Approach 2:
The patent implements a nested structure where different photodiode arrays are stacked vertically within the same device housing. Each layer of photodiodes is nested at a different depth, allowing comprehensive detection functionality to be contained within a single compact structure rather than requiring multiple separate devices.
4Adaptability or versatility
If separate devices are used for visible and near-infrared light capture, then spectral detection is possible, but synchronization issues arise
Solution Approach 1:
The patent combines photodiodes sensitive to different spectral ranges (visible and near-infrared) into a single stacked array, ensuring that all spectral detection occurs simultaneously within the same device. This eliminates the time delays and synchronization issues that arise when using separate devices for different spectral bands.
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 design enhances image processing performance by accurately multiplexing various light wave signals, reducing the computational and manufacturing resources needed for image processing systems.
Implementation Method 1
a photodiode configured to convert photons of incident light into a photocurrent of electrons
Implementation Method 2
A pixel sensor of the CMOS image sensor may include a transfer transistor, which may include a photodiode configured to convert photons of incident light into a photocurrent of electrons
Data Source
AI summary
Some implementations described herein include a complementary metal oxide semiconductor image sensor device and techniques to form the complementary metal oxide semiconductor image sensor device. The complementary metal oxide semiconductor image sensor device includes a includes a first array of photodiodes stacked over a second array of photodiodes. A polarization structure is between the first array of photodiodes and the second array of photodiodes. Signaling generated by the first array of photodiodes (e.g., signaling corresponding to unpolarized light waves) may be multiplexed with signaling generated by the second array of photodiodes (e.g., signaling corresponding to polarized light waves). The complementary metal oxide semiconductor image sensor device further includes a filter structure that filters visible light waves and near infrared light waves amongst the first array of photodiodes and the second array of photodiodes.