Lens Array for Partitioned Image Sensor with Color Filters
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
There is a need for image capture units with lower profiles to reduce the overall size of electronic systems while maintaining optical image quality, and existing technologies face challenges in achieving this without sacrificing resolution or increasing costs due to complex color filter array manufacturing processes.
Innovation Solution
A low profile image capture unit is achieved by using a partitioned image sensor with a lens array where each partitioned area is covered by a respective lens with individual filters, allowing for adjustable focal lengths and radii of curvature to optimize image capture for different colors, and employing multilayer dielectric coatings for cost-effective and efficient color filtering.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Length of moving object
If a conventional image capture unit uses a single imaging lens and image sensor, then the structure is simple, but the profile height is large and cannot be reduced
Solution Approach 1:
The image sensor is divided into multiple partitioned areas (first partitioned area and second partitioned area), and the imaging lens is segmented into multiple lens elements (first lens element and second lens element). Each lens element focuses light of different wavelength components onto corresponding partitioned areas, enabling reduced profile height while maintaining imaging functionality through divided optical paths.
Solution Approach 2:
The patent introduces wavelength dimension as an additional degree of freedom by using achromatic doublet lens elements that focus different wavelength components (first wavelength component and second wavelength component) at different positions. This allows the system to reduce profile height in the vertical dimension while maintaining image quality through spectral separation.
2Length of moving object
If the profile of image capture unit is reduced, then the overall size is decreased, but optical image quality may be sacrificed
Solution Approach 1:
Different lens elements are designed with specific local optical properties optimized for their respective wavelength ranges. The first lens element is optimized for focusing first wavelength component while the second lens element is optimized for second wavelength component, allowing each element to deliver high image quality for its designated spectral range despite the reduced overall profile height.
Solution Approach 2:
The achromatic doublet lens elements combine multiple optical materials with different dispersion properties to correct chromatic aberration. This composite lens structure enables the system to maintain high optical image quality across different wavelength components while achieving a compact profile height, as the combined optical paths of multiple materials compensate for each other's deficiencies.
3Reliability
If color filters are used in partitioned image sensor, then color image capture is improved, but manufacturing complexity and costs increase
Solution Approach 1:
The patent extracts the color filtering function from the traditional Bayer color filter array approach and implements it through spectral separation at the optical level using achromatic doublet lens elements. By separating different wavelength components before they reach the sensor, the system achieves color image capture without requiring complex color filter arrays, thereby reducing manufacturing complexity while maintaining color quality.
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 enables a compact image capture unit with maintained resolution and improved optical quality by allowing for individual adjustment of lenses and filters, reducing manufacturing complexity and costs, and alleviating crosstalk issues in color image capture.
Implementation Method 1
The imaging lens focuses light onto the image sensor to form an image
Implementation Method 2
employing multilayer dielectric coatings for cost-effective and efficient color filtering
Data Source
Figure 1A~1B
Figure 2~3B
Figure 4~5
AI summary
An apparatus includes an image sensor including N image sensor regions arranged thereon. N lens structures are included in a lens array disposed proximate to the image sensor. Each one of the N lens structures is arranged to focus a single image onto a respective one of the N image sensor regions. The N lens structures include a first lens structure having a red color filter, a second lens structure having a green color filter, and a third lens structure having a blue color filter. Each one of the N lens structures includes a glass wafer and a lens formed on the glass wafer. Each one of the red color filter, the green color filter, and the blue color filter is one of coated on the glass wafer underneath the lens and coated over the lens on the glass wafer.