Camera Module Passive Alignment Using Lens Curvature Centers

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Conventional passive alignment methods for camera modules fail to accurately align the optical axis of a lens module with the imaging axis of an image sensor, leading to image degradation due to misalignment, and are not universally applicable to different image sensors and lens modules.

Innovation Solution

A method and apparatus using a programmable multi-axis bond head and autocollimators to determine and align the tilt angles of both the imaging and optical axes by identifying multiple centers of curvature, allowing precise alignment without the need for image grabbers or test charts, and enabling universal application across various camera packages.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If conventional passive alignment is used to adjust tilting between lens housing and substrate, then device complexity is reduced, but manufacturing precision deteriorates due to inaccurate alignment

Engineering Contradiction:

Improvealignment system complexityVSAvoidalignment precision

Core Design Contradiction:

Device complexityVSManufacturing precision

Solution Approach 1:

The patent replaces complex active mechanical alignment systems with a simplified passive alignment system that uses optical references (centers of curvature) embedded in the lens module to determine tilt angles, thereby reducing device complexity while maintaining or improving manufacturing precision

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent introduces centers of curvature as intermediary reference points that mediate between the lens module and image sensor alignment, allowing precise tilt angle determination without requiring complex active alignment equipment

Inventive Principle:

Principle #24Intermediary (Mediator)

2Ease of manufacture

If conventional passive alignment is used without compensating for sensor and lens tilting, then ease of manufacture is improved, but manufacturing precision deteriorates due to unaccounted misalignment

Engineering Contradiction:

Improvealignment process simplicityVSAvoidoptical axis alignment precision

Core Design Contradiction:

Ease of manufactureVSManufacturing precision

Solution Approach 1:

The patent performs preliminary measurement of tilt angles using centers of curvature before the bonding process, allowing the alignment system to pre-calculate compensation values that will be applied during bonding to achieve precise optical axis alignment

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent implements a feedback mechanism where measured tilt angles from centers of curvature are used to calculate and apply compensation values, creating a closed-loop system that improves manufacturing precision while maintaining ease of manufacture

Inventive Principle:

Principle #23Feedback

3Manufacturing precision

If active alignment is used with image grabber and test chart, then manufacturing precision is improved, but device complexity increases and productivity decreases

Engineering Contradiction:

Improvealignment precisionVSAvoidalignment process speed

Core Design Contradiction:

Manufacturing precisionVSProductivity

Solution Approach 1:

The patent extracts and eliminates the need for image grabbers and test charts from the alignment system by using centers of curvature as inherent optical references within the lens module itself, thereby improving productivity while maintaining manufacturing precision

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The patent enables the lens module to serve its own alignment function through its centers of curvature, eliminating the need for external active alignment equipment and test artifacts, thus improving both productivity and precision

Inventive Principle:

Principle #25Self-service

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

Achieves higher bonding accuracy and cost-effectiveness by accurately aligning the optical and imaging axes, reducing the need for extraneous devices and enabling faster tilt measurement and compensation, thus improving the optical performance of camera modules.

Implementation Method 1

determining a tilt angle of an imaging axis of the image sensor

Methodology Applied

Scientific EffectOptical reflection: Reflection

Implementation Method 2

determining a tilt angle of an optical axis of the lens module by using an optical device to identify locations of multiple centers of curvature

Methodology Applied

Scientific EffectOptical focusing: Focusing

Data Source

PatentUS12492893B2Passive alignment of lens module relative to an image sensor for manufacturing a camera module

Publication Date: 2025.12.09 ASMPT SINGAPORE PTE LTD

AI summary

A camera module is manufactured by attaching a lens module to an image sensor. The lens module includes at least one lens element which has a plurality of centers of curvature. A tilt angle of an imaging axis of the image sensor is determined, and a tilt angle of an optical axis of the lens module is also determined by using an optical device to identify locations of multiple centers of curvature of the at least one lens element included in the lens module. At least one of the lens module and the image sensor are then adjusted accordingly so that the imaging axis and the optical axis are aligned, and thereafter, the lens module is fixedly attached with respect to the image sensor to form the camera module.