Autofocus Pixel Microlens Layout for D-Cut Lens Compensation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing camera devices face challenges in achieving accurate autofocusing due to differences in numerical apertures caused by the presence of D-cut lenses with edges extending in specific directions, which affect the arrangement and performance of autofocus pixels.
Innovation Solution
The camera device incorporates a pixel array with first and second autofocus pixels, each having photodiodes arranged in different directions, and microlenses with varying radii of curvature and light transmission layer thicknesses to compensate for the differences in numerical apertures, ensuring accurate autofocusing regardless of lens orientation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If D-cut lenses with edges extending in specific directions are used in the optical module, then the lens structure can be simplified and manufacturing can be facilitated, but differences in numerical apertures are caused that affect the accuracy of autofocusing
Solution Approach 1:
The patent applies local quality by configuring different microlenses with different radii of curvature corresponding to different regions of the pixel array. Specifically, microlenses are divided into first microlenses and second microlenses based on their positional relationships with the D-cut lens edges, with each type having optimized curvature to compensate for regional numerical aperture differences, thereby maintaining uniform autofocusing performance across the entire pixel array.
Solution Approach 2:
The patent changes the radius of curvature parameter of microlenses to compensate for numerical aperture variations. By adjusting this geometric parameter, the optical path and light gathering ability are optimized for different regions, counteracting the asymmetric effects introduced by D-cut lens edges and restoring consistent autofocusing accuracy across the sensor.
2Device complexity
If autofocus pixels are arranged uniformly across the pixel array, then the pixel array structure is simple and manufacturing is easy, but the differences in numerical apertures caused by D-cut lens edges result in inconsistent autofocusing performance
Solution Approach 1:
The patent implements local quality by differentiating microlense configurations based on their spatial relationships with D-cut lens edges. The pixel array is divided into regions with first microlenses and regions with second microlenses, each optimized for their specific optical environment. This localized optimization ensures reliable autofocusing performance while maintaining overall structural organization.
Solution Approach 2:
The patent segments the microlense configuration into distinct types (first microlenses and second microlenses) based on their positional relationships with the D-cut lens edges. This segmentation allows each segment to be optimized independently for its specific numerical aperture conditions, improving overall system reliability without creating excessive complexity.
3Measurement precision
If microlenses with different radii of curvature are used to compensate for numerical aperture differences, then autofocusing accuracy is improved, but the manufacturing precision requirements increase
Solution Approach 1:
The patent applies local quality by implementing different microlense curvature specifications only in regions where D-cut lens edges cause numerical aperture variations. Rather than requiring precision across the entire array, the differentiated configuration is applied locally to affected regions, reducing overall manufacturing complexity while maintaining autofocus accuracy where needed.
Solution Approach 2:
The patent introduces asymmetric microlense configurations (different radii of curvature for first and second microlenses) to counterbalance the asymmetric optical path differences caused by D-cut lens edges. This asymmetric design compensates for the inherent asymmetry in the optical system, restoring uniform autofocusing performance without requiring excessive manufacturing 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
This configuration enhances the accuracy and effectiveness of the autofocusing function by adjusting the height and curvature of microlenses and light transmission layers, thereby improving the camera's ability to focus on subjects despite the presence of D-cut lenses.
Implementation Method 1
each of the plurality of pixels includes a pixel circuit, at least one photodiode, a light transmission layer, and a microlens that are sequentially stacked
Data Source
AI summary
A camera device includes an image sensor including a pixel array and a logic circuit, with the camera device further comprising an optical module that includes a plurality of lenses arranged in a path of travel of light incident on the image sensor. The pixel array includes a plurality of pixels having a general pixel, a first autofocus pixel and a second autofocus pixel, and at least one of the plurality of lenses has an edge that extends in a first direction. A height of an upper surface of the microlens, included in the first autofocus pixel, is different from a height of an upper surface of the microlens included in the second autofocus pixel.