Photoelectric Conversion Element Structure for Dynamic Range and Low Power
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current CMOS imaging sensors face limitations in dynamic range and power consumption, particularly in portable devices like mobile phones, which affect image quality and continuous operating time.
Innovation Solution
The proposed imaging device incorporates a photoelectric conversion element with n-type and p-type semiconductors, along with specific transistor and capacitor configurations, utilizing an i-type semiconductor to enhance light detection sensitivity and reduce power consumption.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If conventional CMOS imaging sensors are used, then device complexity is low and manufacturing is easy, but dynamic range is limited and power consumption is high
Solution Approach 1:
The imaging device is divided into multiple pixel types (first pixels with first photoelectric conversion elements, second pixels with second photoelectric conversion elements) that have different structures and functions. This segmentation allows each pixel type to be optimized for specific imaging conditions, thereby expanding the overall dynamic range without requiring complete redesign of the entire sensor
Solution Approach 2:
Different regions of the imaging device are assigned different photoelectric conversion element configurations. First pixels are designed with specific characteristics for certain lighting conditions while second pixels are designed with different characteristics for other conditions. This local differentiation enables the device to handle a wider range of lighting scenarios, improving adaptability and dynamic range
2Duration of action of stationary object
If conventional CMOS imaging sensors are used, then device structure is simple, but power consumption is high affecting continuous operating time
Solution Approach 1:
The imaging device employs different readout strategies for first and second pixels, where first pixels are read out during certain periods and second pixels are read out during other periods. This periodic action allows the device to manage power consumption by activating and reading different pixel types at different times, thereby extending continuous operating time while maintaining imaging capability
Solution Approach 2:
The device dynamically selects which pixel type to read out based on imaging conditions and power requirements. By making the readout process dynamic rather than static, the system can adapt to varying power constraints and extend operating time while maintaining image quality
3Reliability
If conventional CMOS imaging sensors are used, then manufacturing process is standard and simple, but image quality under variety of environments is insufficient
Solution Approach 1:
The imaging device integrates multiple pixel types with different photoelectric conversion element configurations within a single sensor array. This multi-functional design allows the device to maintain high image quality across various lighting and environmental conditions while still being manufactured using adapted CMOS processes, balancing reliability with manufacturability
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 improves the dynamic range and image quality, reduces power consumption, and increases productivity while providing a novel imaging solution with high light receiving sensitivity and wide temperature range operation.
Implementation Method 1
a photoelectric conversion element, first to fourth transistors, a capacitor, and first to seventh wirings. The photoelectric conversion element includes an n-type semiconductor and a p-type semiconductor
Data Source
AI summary
A solid-state imaging device with high productivity and improved dynamic range is provided. In the imaging device including a photoelectric conversion element having an i-type semiconductor layer, functional elements, and a wiring, an area where the functional elements and the wiring overlap with the i-type semiconductor in a plane view is preferably less than or equal to 35%, further preferably less than or equal to 15%, and still further preferably less than or equal to 10% of the area of the i-type semiconductor in a plane view. Plural photoelectric conversion elements are provided in the same semiconductor layer, whereby a process for separating the respective photoelectric conversion elements can be reduced. The respective i-type semiconductor layers in the plural photoelectric conversion elements are separated by a p-type semiconductor layer or an n-type semiconductor layer.