Camera Module Actuator Inductance Position Detection

Solution Overview

Problem

Existing camera module actuators rely on hall sensors to detect magnet position, which increases manufacturing costs and reduces space efficiency, while also being less precise in position detection.

Innovation Solution

An actuator system that uses a magnet, a driving coil, and a position calculation processor with sensing coils to calculate the magnet's position based on inductance level changes, eliminating the need for hall sensors and improving precision.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If hall sensors are used to detect magnet position, then position detection can be achieved, but manufacturing cost increases and space efficiency decreases

Engineering Contradiction:

Improveposition detection precisionVSAvoiddevice complexity

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The patent extracts the position detection function from the traditional hall sensor and relocates it to the existing coil structure. By using the coil's inductance changes caused by magnet position variations, the system eliminates the need for separate hall sensors while maintaining position detection capability. This reduces device complexity and manufacturing cost without sacrificing measurement precision.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The coil structure is given multiple functions: it serves both as the driving coil for magnet actuation and as the sensing coil for position detection. The same coil structure that generates electromagnetic force to move the magnet also detects its position through inductance changes. This multi-functionality reduces the number of components needed and simplifies the overall device structure.

Inventive Principle:

Principle #6Universality (Multi-functionality)

2Measurement precision

If hall sensors are used to detect magnet position, then position information can be obtained, but manufacturing cost increases

Engineering Contradiction:

Improveposition detection precisionVSAvoidmanufacturing cost

Core Design Contradiction:

Measurement precisionVSEase of manufacture

Solution Approach 1:

The coil structure is given multiple functions: it serves both as the driving coil for magnet actuation and as the sensing coil for position detection. The same coil structure that generates electromagnetic force to move the magnet also detects its position through inductance changes. This multi-functionality reduces the number of components needed and simplifies the overall device structure.

Inventive Principle:

Principle #6Universality (Multi-functionality)

Solution Approach 2:

The patent merges the driving coil and sensing coil into a single integrated structure. Instead of having separate components for actuation and detection, the system uses one coil that performs both functions. This consolidation reduces manufacturing complexity and cost while maintaining the ability to precisely detect magnet position through inductance measurements.

Inventive Principle:

Principle #5Merging (Combining)

3Measurement precision

If hall sensors are used to detect magnet position, then position detection can be performed, but space efficiency decreases

Engineering Contradiction:

Improveposition detection precisionVSAvoidspace efficiency

Core Design Contradiction:

Measurement precisionVSArea of stationary object

Solution Approach 1:

The patent extracts the position detection function from the traditional hall sensor and relocates it to the existing coil structure. By using the coil's inductance changes caused by magnet position variations, the system eliminates the need for separate hall sensors while maintaining position detection capability. This reduces device complexity and manufacturing cost without sacrificing measurement precision.

Inventive Principle:

Principle #2Taking out (Extraction)

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 system effectively detects the magnet's position with high precision, reduces manufacturing costs, and optimizes space usage by eliminating the need for hall sensors and enhancing the camera module's autofocusing and optical image stabilization capabilities.

Implementation Method 1

a position calculation processor including sensing coils, and configured to calculate a position of the magnet according to inductance levels of an inductor of the sensing coils, wherein the inductance levels vary according to movements of the magnet

Methodology Applied

Scientific EffectElectromagnetic induction: Electromagnetic Induction

Implementation Method 2

a driver configured to move the magnet in at least one of an optical axis direction and a direction perpendicular to the optical axis by applying a driving signal to the driving coil

Methodology Applied

Scientific EffectElectromagnetic force: Lorentz Force

Data Source

PatentUS11163211B2Camera module actuator

Publication Date: 2021.11.02 SAMSUNG ELECTRO MECHANICS CO LTD

AI summary

An actuator includes a magnet, a driving coil facing the magnet, a driver, and a position calculation processor. The driver is configured to move the magnet in at least one of an optical axis direction and a direction perpendicular to the optical axis by applying a driving signal to the driving coil. The position calculation processor includes sensing coils, and is configured to calculate a position of the magnet according to inductance levels of an inductor of the sensing coils. The inductance levels vary according to movements of the magnet.