Image Sensor Cyclic Pixel Arrangement for Dynamic Range Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing image sensors with a combination of 1 pixel for luminance and 3 pixels for color signals lack a description of pixel control methods for realizing image pickup using the Spatially Varying Exposure (SVE) system, limiting the dynamic range and performance enhancement.
Innovation Solution
An image pickup device with 4 types of spectral sensitivities, including panchromatic sensitivity, arranged in a cyclic 4×4 checkerboard pattern, utilizing three pixel transfer control signal lines per line to control exposure timings and sharing A/D converters and floating diffusion nodes, enabling interpolation and conversion of signals for improved dynamic range and performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If pixels with different sensitivities are arranged in SVE system using electronic shutter control, then dynamic range is enlarged, but device complexity increases due to multiple pixel transfer control signal lines
Solution Approach 1:
The image sensor is divided into multiple pixel types with different spectral sensitivities (R, G1, G2, B) arranged in a cyclic pattern. Each pixel type is controlled by dedicated pixel transfer control signal lines, segmenting the control mechanism to manage complexity while enabling differential exposure control for enhanced dynamic range
Solution Approach 2:
The patent implements dynamic exposure control by independently adjusting the exposure timing for each pixel type through separate pixel transfer control signal lines. This allows the system to adaptively optimize capture parameters for different spectral ranges, enlarging the overall dynamic range while managing complexity through structured control
2Adaptability or versatility
If 4 types of pixels with different spectral sensitivities are arranged in cyclic pattern, then image capture capability is improved, but manufacturing precision requirements increase
Solution Approach 1:
The patent employs an asymmetric cyclic arrangement of pixel types (R, G1, G2, B) where each pixel type occupies specific positions in a repeating pattern. This asymmetric design enables versatile image capture across different spectral ranges while the periodic nature of the pattern provides manufacturing tolerance to precise positioning variations
Solution Approach 2:
Different pixel types are assigned specific spectral sensitivity characteristics and positioned in localized regions according to the cyclic pattern. Each pixel type optimizes capture for its specific spectral range, and the local arrangement allows for targeted optimization of image capture capability while accommodating manufacturing variations
3Measurement precision
If multiple pixel transfer control signal lines are used for exposure control, then exposure timing precision is improved, but device complexity increases
Solution Approach 1:
The control system is segmented into multiple independent pixel transfer control signal lines, each dedicated to controlling specific pixel types. This segmentation enables precise exposure timing control for each pixel type while organizing the complexity into manageable, modular control pathways
Solution Approach 2:
The pixel transfer control signal lines serve multiple functions: they control exposure timing, manage charge transfer timing, and coordinate readout sequences. This multi-functionality reduces the need for separate dedicated circuits for each function, managing device complexity while maintaining exposure timing precision
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 effectively enlarges the dynamic range and improves performance by allowing for precise control of exposure timings and signal processing across different spectral sensitivities, enhancing image capture capabilities.
Implementation Method 1
Pixels of normal image sensors include a photodiode (PD) that converts incident light into charges by a photoelectric conversion
Data Source
AI summary
[Object] The present technique relates to an image pickup device, an image pickup method, and a program that enables pixels having 4 types of spectral sensitivities to be controlled while changing exposure times.[Solving Means] The present technique is applicable to an image pickup device including pixels having 4 types of spectral sensitivities, that include pixels having a panchromatic spectral sensitivity and are arranged on an image pickup surface, pixels that realize a first exposure and pixels that realize a second exposure different from the first exposure being arranged on the image pickup surface with respect to the 4 types of spectral sensitivities. Further, a first line in which first pixels having the panchromatic spectral sensitivity are arranged in a two-pixel cycle in a specific direction and a second line in which the first pixels are arranged while deviating by one pixel from the first line in the specific direction are arranged alternately in a direction orthogonal to the specific direction, and pixels having spectral sensitivities different from the spectral sensitivity of the first pixels are arranged in a 2- or 4-pixel cycle in the specific direction for each of the spectral sensitivities and 2-dimensionally constitute a cyclic arrangement of 4×4 pixels in which the first spectral sensitivity pixels are arranged in a checkerboard arrangement.