Stacked Imaging Device with Independent Pixel Block Exposure Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing imaging devices face limitations in achieving improved performance and dynamic range due to uniform exposure times across pixel blocks, leading to insufficient gradations in varying light conditions.
Innovation Solution
The implementation of a stacked imaging device configuration with a first chip containing pixel blocks and a second chip equipped with selection circuits, timing generators, and signal processing units, allowing for independent control of charge accumulation time across pixel blocks, enabling varied exposure times based on light intensity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If uniform exposure time is applied across all pixel blocks, then device complexity is reduced, but dynamic range and image quality deteriorate due to insufficient gradations in varying light conditions
Solution Approach 1:
The pixel array is divided into multiple pixel blocks, each with independent exposure time control. The control circuit is segmented into multiple selection circuits, with each selection circuit corresponding to a specific pixel block and capable of independently selecting exposure time periods. This segmentation enables different exposure times for different spatial regions, improving dynamic range while keeping each control unit relatively simple.
Solution Approach 2:
Different pixel blocks are assigned different exposure times based on local lighting conditions. The selection circuits enable each pixel block to have customized exposure parameters tailored to its specific imaging requirements, allowing bright regions to use shorter exposure times and dark regions to use longer exposure times, thereby optimizing local image quality.
2Manufacturing precision
If longer exposure time is used for dark areas, then gradation quality improves, but bright areas become saturated
Solution Approach 1:
The exposure time for each pixel block is dynamically adjusted based on local lighting conditions. The selection circuits can select from multiple exposure time periods, enabling the system to adaptively optimize exposure parameters for each region. This dynamic control prevents saturation in bright areas while ensuring sufficient gradations in dark areas.
Solution Approach 2:
The exposure time parameter is varied across different pixel blocks rather than being uniform. Each selection circuit can choose different exposure time periods, effectively changing the exposure parameter to match local lighting conditions. This parameter variation resolves the contradiction between capturing detail in dark areas and avoiding saturation in bright areas.
3Adaptability or versatility
If independent exposure time control is implemented for each pixel block, then dynamic range is improved, but device complexity increases
Solution Approach 1:
Multiple pixel blocks share common control resources through the selection circuit architecture. Each selection circuit can control its corresponding pixel block independently, but the overall system uses a unified control structure where selection circuits work in parallel. This multi-functionality approach provides independent control flexibility while avoiding the complexity of fully decentralized control.
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 enhances the dynamic range of the imaging device by allowing for tailored exposure times across different pixel blocks, preventing saturation and ensuring sufficient gradations in both bright and dark areas.
Implementation Method 1
a plurality of pixels arranged in a matrix... pixels that convert incident light into electrical signals
Data Source
AI summary
An imaging device includes a first chip on which a plurality of first blocks is arranged in a matrix, and a second chip which includes a first block scanning circuit and a second block scanning circuit. The second chip includes a selection circuit configured to select driving timing given to a plurality of pixels, based on a signal output from the first block scanning circuit and a signal output from the second block scanning circuit. A second block includes a circuit other than the selection circuit.