Camera Module Active Alignment Tilt Correction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional camera module active alignment methods have low throughput, making it difficult and expensive to achieve high-resolution image quality in mass-produced small form factor cameras, as manufacturing tolerances lead to optical misalignment issues like tilt and decenter between the lens and sensor, resulting in image quality degradation, especially at the edges.
Innovation Solution
A method that involves capturing a single test image to calculate optical tilt between the lens and image sensor using spatial frequency response data, and mechanically adjusting the alignment to reduce optical tilt, allowing for high-throughput active optical tilt alignment correction in camera modules.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If conventional mechanical alignment process is used, then throughput is high, but manufacturing precision deteriorates due to tilt and decenter between lens and sensor
Solution Approach 1:
The patent replaces traditional mechanical alignment methods with an optical-based active alignment system. The system uses an optical sensor to detect the optical axis of the lens and compares it with the mechanical axis, then uses a motorized stage to automatically adjust the lens position. This substitution of mechanical alignment with optical detection and automated control resolves the contradiction by achieving high precision alignment while maintaining throughput through automation.
Solution Approach 2:
The patent implements a feedback control system where the optical sensor continuously monitors the optical axis position, and the system automatically adjusts the lens position based on the detected deviation. The feedback loop compares the measured optical axis with the desired position and makes real-time corrections, ensuring high alignment precision while maintaining efficient throughput through automated closed-loop control.
2Manufacturing precision
If conventional active alignment method is used, then manufacturing precision is improved, but productivity deteriorates due to low throughput
Solution Approach 1:
The patent replaces manual or semi-automated active alignment methods with a fully automated system that uses optical sensors and motorized stages. This automation eliminates the time-consuming manual adjustment process while maintaining high alignment precision, thereby resolving the contradiction between manufacturing precision and productivity.
Solution Approach 2:
The patent changes the operational parameters of the alignment system by using optical detection parameters instead of mechanical measurement parameters. The system measures optical axis position using light-based sensors and adjusts positions using motorized control, which enables faster measurement and adjustment cycles compared to traditional mechanical methods, thus improving throughput while maintaining precision.
3Productivity
If manufacturing tolerances are relaxed, then productivity is improved, but manufacturing precision deteriorates resulting in image quality degradation
Solution Approach 1:
The patent uses feedback control to compensate for variations within manufacturing tolerances. The optical sensor detects actual alignment deviations caused by tolerance variations, and the automated adjustment system corrects these deviations in real-time. This feedback mechanism enables the system to produce high-precision aligned camera modules even when component tolerances are relatively loose, thus maintaining both productivity and manufacturing precision.
Solution Approach 2:
The patent transforms fixed mechanical alignment parameters into dynamically adjustable optical parameters. By using optical detection and motorized adjustment, the system can adapt to tolerance variations in each component while maintaining consistent alignment quality. This parameter flexibility allows mass production with relaxed tolerances without sacrificing final alignment precision.
Data Source
AI summary
Some embodiments include methods for correcting optical alignment of components in a camera module for a multifunction device. In some embodiments, components of a camera module for use in a multifunction device are assembled on a test station. Some embodiments include a method that includes capturing a single test image, calculating from the spatial frequency response data an optical tilt between the optical axis of a lens and an optical axis of the image sensor of the camera module, and mechanically adjusting an alignment of the lens and the optical axis of the image sensor of the camera module to reduce the optical tilt. In some embodiments, the capturing is performed using the components of the camera module, and the single test image contains visually encoded spatial frequency response data for characterizing the components of the camera module.