CCD Image Sensor Same-Color Pixel Binning
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current CCD image sensors with sparse CFA patterns face limitations in color binning efficiency, particularly in reducing image resolution while maintaining light sensitivity and speed, often requiring additional hardware or complex clocking systems.
Innovation Solution
The implementation of CCD image sensors with VCCD and HCCD structures that facilitate binning of same-color pixels without the need for two separate HCCDs or additional VCCDs, using a configuration with more horizontal shift elements than VCCDs to achieve efficient readout for both sparse and Bayer CFA patterns.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If color binning is performed to reduce the number of charge packets, then readout speed increases, but image resolution decreases
Solution Approach 1:
The pixel array is segmented into color groups (red, green, blue) and readout is performed separately for each color group. This allows binning within each color group to improve readout speed while preserving the ability to maintain higher resolution by processing colors independently rather than combining all colors into single packets.
2Productivity
If additional VCCDs or HCCDs are used to improve color binning efficiency, then readout efficiency increases, but device complexity increases
Solution Approach 1:
The existing VCCDs and HCCDs are made multi-functional by configuring them to handle multiple color groups. The same CCD structures perform both vertical charge transfer and color-specific binning operations, eliminating the need for additional dedicated CCDs for each color group and reducing overall device complexity.
Solution Approach 2:
The CCD structure is made dynamically reconfigurable through phase clocking schemes that can be adjusted to perform different binning operations. By dynamically changing the clocking phases, the same hardware structure adapts to different color binning requirements without requiring additional physical components.
3Productivity
If binning operations are performed to increase frame rate, then productivity increases, but measurement precision may be affected
Solution Approach 1:
Color information is segmented into separate charge packets for each color group before binning. This segmentation preserves color specificity during the binning process, allowing frame rate increases through binning while maintaining color accuracy by keeping color channels distinct until the final readout stage.
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 approach enhances readout efficiency by allowing for improved binning of same-color pixels, increasing frame rate, and maintaining photographic speed equivalence between color and panchromatic pixels without reducing light sensitivity or introducing aliasing errors.
Implementation Method 1
vertical and horizontal CCDs are used to transfer collected charge from the photodiodes or other photosensitive elements of the pixel array
Implementation Method 2
A typical electronic image sensor comprises a number of photodiodes or other photosensitive elements arranged in a two-dimensional array
Implementation Method 3
the image sensor is configured with color filter elements of a color filter array (CFA) arranged over respective ones of the pixels
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A CCD image sensor comprises photosensitive elements arranged in rows and columns, vertical CCDs each having vertical shift elements associated with respective ones of the photosensitive elements of a corresponding one of the columns, and a horizontal CCD coupled to each of the vertical CCDs. The horizontal CCD comprises horizontal shift elements of two different types interspersed with one another. The horizontal shift elements of the first type are configured to receive shifted charge packets directly from respective ones of the vertical CCDs. The horizontal shift elements of the second type are configured not to receive shifted charge packets directly from any of the vertical CCDs. This configuration facilitates binning of same-color pixels for both sparse CFA patterns and Bayer CFA patterns.