Dual Lens Driving Magnet Layout for Close-Spaced Camera Modules

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Dual camera devices experience magnetic field interference due to the proximity of camera modules, making it difficult to reduce the separation distance between their optical axes.

Innovation Solution

A lens driving device with a specific arrangement of magnets and coils, including a third coil facing at least one of the first and second magnets, and Hall sensors positioned to minimize magnetic interference, allowing for closer placement of camera modules.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Volume of moving object

If two camera devices are deployed in proximity to reduce separation distance, then the device size is reduced, but magnetic field interference occurs between the camera modules

Engineering Contradiction:
Improvecamera module sizeVSAvoidmagnetic field interference
Core Design Contradiction:
Volume of moving objectVSObject-affected harmful factors

Solution Approach 1:

A non-magnetic material (such as plastic or ceramic) is introduced as an intermediary substance between the magnets of the first and second camera modules. This intermediary blocks or shields the magnetic field interference while allowing the camera modules to be positioned in close proximity, thus reducing the overall device size without suffering from magnetic interference

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The magnetic interference problem is isolated and addressed by removing the harmful magnetic field interaction between the two camera modules. This is achieved by placing non-magnetic materials between the magnets, effectively extracting or eliminating the interference pathway while maintaining the functional magnets for their respective optical image stabilization purposes

Inventive Principle:
Principle #2Taking out (Extraction)

2Device complexity

If magnets are positioned close together for compact design, then the device complexity is reduced, but magnetic field interference prevents proper operation

Engineering Contradiction:
Improvemagnet arrangement complexityVSAvoidcamera module operation
Core Design Contradiction:
Device complexityVSReliability

Solution Approach 1:

Non-magnetic materials are placed between the magnets of adjacent camera modules to act as shields or barriers. This allows the magnets to be positioned close together for compact design without causing magnetic field interference that would disrupt the operation of the optical image stabilization function

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The magnetic shielding is applied locally only in the regions where magnetic field interference occurs between adjacent camera modules, rather than requiring complete redesign of the magnet arrangement. This allows compact positioning while maintaining operational reliability through targeted local intervention

Inventive Principle:
Principle #3Local quality

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 prevents magnetic field interference and reduces the size of the camera module by minimizing the gap between closed-loop auto focus actuators.

Implementation Method 1

a coil (310, 320) disposed on the bobbin; a magnet (410, 420, 430, 440, 450, 460, 470) disposed to face the coil (310, 320)

Methodology Applied
Scientific EffectElectromagnetic induction: Electromagnetic Induction

Implementation Method 2

a Hall sensor (750, 760) disposed to face the magnet (710, 720)

Methodology Applied
Scientific EffectHall effect: Hall Effect

Data Source

PatentEP3779588B1Lens driving device and camera device comprising same
Publication Date: 2025.10.08 LG INNOTEK CO LTD
  • EP3779588B1 patent drawingFigure 1
  • EP3779588B1 patent drawingFigure 2
  • EP3779588B1 patent drawingFigure 3

AI summary

The present embodiment relates to a lens driving device comprising: a housing comprising a first hole and a second hole; a first bobbin disposed in the first hole of the housing; a second bobbin disposed in the second hole of the housing; a first coil disposed on the first bobbin; a second coil disposed on the second bobbin; a first magnet disposed in the housing to face the first coil; a second magnet facing the second coil; and a third magnet disposed between the first coil and the second coil.