Lens Device Dust Protection via Partition Wall
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing lens devices face issues with dust entry due to exposed detection components, leading to potential breakdowns and contamination within the lens barrel.
Innovation Solution
A lens device design featuring a movable lens with a holding member extending along the optical axis, incorporating a detecting part within a closed storage space, which prevents dust entry by using a partition wall to isolate the detection mechanism from the lens movement area.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the detecting part is exposed on the outer peripheral surface of the lens barrel, then the position detection can be performed, but dust may enter and cause breakdown
Solution Approach 1:
The lens barrel is divided into two separate spaces: a first space for the movable lens and a second space for the detecting part. This segmentation isolates the detecting part from dust in the lens movement area while maintaining its position detection function through the partition wall.
Solution Approach 2:
A partition wall is introduced as an intermediary structure between the movable lens space and the detecting part space. The partition wall allows magnetic field penetration for position detection while physically blocking dust from reaching the detecting part.
2Measurement precision
If a hole is formed between magnetoresistive element and magnet for detection, then position detection is enabled, but dust may enter the focus moving body space
Solution Approach 1:
The partition wall serves as an intermediary that allows magnetic field interaction between the magnet and magnetoresistive element for precise position detection while preventing dust from passing through to contaminate the focus moving body space.
Solution Approach 2:
The partition wall acts as a thin barrier structure that is permeable to magnetic fields but impermeable to dust particles, enabling both detection functionality and dust protection.
3Measurement precision
If the photo-interrupter is present in the lens barrel, then position detection is achieved, but dust caused by the photo-interrupter enters the lens barrel
Solution Approach 1:
The lens barrel is segmented into separate spaces, placing the photo-interrupter in an isolated area away from the main lens barrel interior. This prevents dust generated by the photo-interrupter from contaminating the lens barrel while maintaining measurement capability.
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
The solution effectively protects the detection mechanism from dust and contamination, ensuring reliable operation and maintaining a clean environment for the movable lens within the lens barrel.
Implementation Method 1
a magnetoresistive element that detects changes in magnetic flux of a magnet in accordance with a position of the magnet in a direction of an optical axis
Data Source
AI summary
There is provided a lens device that prevents dust from entering a space in which a movable lens is moved. A movable lens is moved in the direction of an optical axis. A holding member, which extends in the direction of the optical axis, is formed at an end portion of the movable lens. A magnet is fixed to an end portion of the holding member. A hall IC is disposed in a closed storage space at a position facing the magnet. A signal, which corresponds to the position of the magnet in the direction of the optical axis, is output from the hall IC. Since the hall IC is disposed in the storage space closed by a storage box, the entry of dust, which is caused by the hall IC, into a space in which the movable lens is moved is prevented.