Plastic Lens Barrel with Optical Aligning Structure
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional optical lens systems with injection-molded plastic lens barrels face issues such as poor melt flow rates, leading to improper assembly, dust ingress, and increased complexity in automated production due to large dimensional tolerances, which hinder the miniaturization and multi-functionality of optical systems.
Innovation Solution
The imaging lens module incorporates a plastic lens barrel with a tapered object-end surface, a quadrilateral or rectangular bottom surface, and an optical aligning structure within the second inner hole portion, along with three gate traces, to ensure precise alignment and assembly of the imaging lens assembly with the image sensor, maintaining a standard deviation of gate trace distances within a specific range relative to the optical axis, thereby improving manufacturing efficiency and reducing assembly deviations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If injection molding is used to manufacture the plastic lens barrel, then manufacturing cost is reduced and shape design flexibility is increased, but dimensional tolerance becomes overly large leading to improper assembly and dust ingress
Solution Approach 1:
The lens barrel is divided into multiple segments: a plastic lens barrel and a metal lens barrel. The metal lens barrel is inserted into the plastic lens barrel to form a composite structure. This segmentation allows the plastic portion to provide cost-effective mass production through injection molding while the metal portion provides precise dimensional tolerance and assembly alignment, thereby resolving the contradiction between ease of manufacture and manufacturing precision.
2Ease of manufacture
If injection molding is used to manufacture the plastic lens barrel, then manufacturing cost is reduced, but assembly precision deteriorates due to improper assembly and offset
Solution Approach 1:
The metal lens barrel acts as an intermediary component between the plastic lens barrel and the imaging lens assembly. It provides precise positioning features such as positioning holes and positioning protrusions that ensure accurate assembly alignment. This intermediary structure allows the plastic lens barrel to be manufactured cost-effectively while maintaining high assembly precision through the metal component's precise geometry.
3Productivity
If the plastic lens barrel structure is simplified for mass production, then productivity is improved, but assembly stability deteriorates due to dust ingress and misalignment
Solution Approach 1:
The lens barrel employs a composite material structure combining plastic and metal materials. The plastic lens barrel provides cost-effective mass production capability through injection molding, while the metal lens barrel inserted within it provides structural stability, precise alignment, and dust protection. This composite structure maintains both high productivity and assembly stability by leveraging the advantages of each material.
4Ease of operation
If dimensional tolerance of the plastic lens barrel is increased to facilitate automated production, then ease of operation is improved, but assembly precision deteriorates due to offset and skew
Solution Approach 1:
The lens barrel is segmented into plastic and metal portions, each serving different functional requirements. The plastic portion can be manufactured with relaxed tolerances suitable for automated production, while the metal portion provides precise positioning features with tight tolerances. This segmentation allows automated production to operate with easier tolerances while maintaining high assembly precision through the metal component's precise geometry.
Data Source
AI summary
An imaging lens module includes an imaging lens assembly, an image sensor and a plastic lens barrel. The image sensor is disposed on an image side of the imaging lens assembly and has an image sensing surface through which an optical axis of the imaging lens assembly passes. The plastic lens barrel includes an object-end portion, a bottom portion, a first inner hole portion and a second inner hole portion. An object-end surface of the object-end portion faces towards an object side direction of the imaging lens assembly. A tapered surface of the object-end portion is tapered off towards the object-end surface. The bottom portion is located on an image side of the object-end portion. The imaging lens assembly is disposed in the first inner hole portion. The second inner hole portion located on an image side of the first inner hole portion and includes an optical aligning structure.