Subpixel Imaging Sensor Layout for HDR and Autofocus
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional solid-state imaging devices face challenges in achieving both high dynamic range operation and auto focus operation in pixel configurations with multiple subpixels, due to limitations in miniaturization and the need for additional elements to control separation potential.
Innovation Solution
A solid-state imaging device with a pixel configuration that includes a first pixel separation region, a second pixel separation region, and an overflow region, where the overflow region allows signal charges to overflow between subpixels, and is formed between a first and a second subpixel, enabling both high dynamic range and auto focus operations without requiring additional elements.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If an element for controlling separation potential is added to achieve auto focus operation, then auto focus capability is improved, but device complexity increases and area for miniaturization is reduced
Solution Approach 1:
The pixel separation region is designed to serve multiple functions: it separates adjacent photodiodes to prevent charge diffusion, establishes potential barriers for charge accumulation, and enables auto focus operation through potential control. This multi-functionality eliminates the need for separate dedicated elements, reducing device complexity while maintaining auto focus capability.
Solution Approach 2:
The invention merges the charge separation function and the auto focus control function into a single pixel separation region structure. By integrating these functions, the patent avoids adding separate controlling elements, thereby preventing increase in device complexity and preserving miniaturization progress.
2Productivity
If subpixels are miniaturized to increase pixel density, then productivity is improved, but area for additional control elements is reduced
Solution Approach 1:
The pixel separation region performs multiple functions including charge separation, potential barrier formation, and auto focus control within a compact structure. This multi-functionality allows miniaturization of subpixels without requiring additional dedicated space for control elements, as the same structure fulfills multiple roles.
Solution Approach 2:
The patent applies different impurity concentrations in specific regions (higher impurity concentration in pixel separation regions, lower impurity concentration in photodiode regions) to optimize local properties. This localized differentiation allows efficient use of space, enabling subpixel miniaturization while maintaining necessary control functions within the available area.
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
The solution allows for effective high dynamic range operation and auto focus operation in a pixel configuration with multiple subpixels, improving image quality by reducing crosstalk and sensitivity differences between subpixels.
Implementation Method 1
a photodiode, and accumulates charges by photoelectric conversion
Data Source
AI summary
Provided is a solid-state imaging device and an electronic apparatus capable of achieving both of a high dynamic range operation and an auto focus operation in a pixel configuration in which a plurality of unit pixels includes two or more subpixels. The solid-state imaging device includes a first pixel separation region that separates a plurality of unit pixels including two or more subpixels, a second pixel separation region that separates each of the plurality of unit pixels separated by the first pixel separation region and an overflow region that causes signal charges accumulated in the subpixels to overflow to at least one of adjacent subpixels, in which the overflow region is formed between a first subpixel and a second subpixel.