Actuator Guide Curvature Aligns Rotation Center

Solution Overview

Problem

Existing actuators for driving reflectors in camera modules, used for Optical Image Stabilization (OIS), face issues due to the non-coincidence of the center of curvature of the guide rail and the center of rotation of the reflector, leading to varying amounts of rotation based on the position of the moving body, necessitating additional compensation algorithms.

Innovation Solution

The actuator design ensures that the center of curvature of the rotation guide coincides with the center of rotation of the reflector, allowing for consistent rotation amounts regardless of the moving body's position, achieved through a specific configuration of guides, balls, and magnets.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If a guide rail is formed in each of the moving body and the fixed body with balls arranged therebetween, then the moving body can rotationally move along the guide rail, but the center of curvature of the guide rail and the center of rotation of the reflector do not coincide, causing varying rotation amounts depending on position

Engineering Contradiction:

Improverotational movement along guide railVSAvoidrotation amount consistency

Core Design Contradiction:

Ease of operationVSManufacturing precision

Solution Approach 1:

The guide rail is designed with a curved path where the center of curvature coincides with the center of rotation of the reflector. This curvature alignment ensures that the rotational movement follows a precise arc, maintaining consistent rotation amounts regardless of the moving body's position along the guide rail.

Inventive Principle:

Principle #14Spheroidality (Curvature)

Solution Approach 2:

The invention changes the geometric parameters of the guide rail by adjusting its curvature radius and path configuration. By setting the center of curvature of the guide rail to coincide with the center of rotation of the reflector, the system achieves uniform rotational characteristics throughout the movement range, eliminating position-dependent variations in rotation amount.

Inventive Principle:

Principle #35Parameter changes

2Ease of manufacture

If the center of curvature of the guide rail and the center of rotation of the reflector do not coincide, then the structure is simpler to manufacture, but separate compensation algorithms are required for each position

Engineering Contradiction:

Improveguide rail structureVSAvoidcompensation algorithm

Core Design Contradiction:

Ease of manufactureVSDevice complexity

Solution Approach 1:

The guide rail is designed with a curved path where the center of curvature coincides with the center of rotation of the reflector. This curvature alignment ensures that the rotational movement follows a precise arc, maintaining consistent rotation amounts regardless of the moving body's position along the guide rail.

Inventive Principle:

Principle #14Spheroidality (Curvature)

Solution Approach 2:

The invention changes the geometric parameters of the guide rail by adjusting its curvature radius and path configuration. By setting the center of curvature of the guide rail to coincide with the center of rotation of the reflector, the system achieves uniform rotational characteristics throughout the movement range, eliminating position-dependent variations in rotation amount.

Inventive Principle:

Principle #35Parameter changes

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

This design eliminates the need for separate compensation algorithms, ensures balanced physical support, and improves the precision and stability of Optical Image Stabilization by maintaining consistent rotation across different positions with the same driving force.

Implementation Method 1

a first drive coil configured to generate an electromagnetic force in the first magnet to rotationally move the movement frame in a first direction based on the first support frame

Methodology Applied

Scientific EffectElectromagnetic force: Lorentz Force

Implementation Method 2

a first ball inside the first rotation guide, in which a center of curvature of the first rotation guide corresponds to a center of rotation of the reflector

Methodology Applied

Scientific EffectBall bearing: Ball Bearing

Data Source

PatentUS12216330B2Actuator for driving reflector

Publication Date: 2025.02.04 JAHWA ELECTRONICS

AI summary

An actuator for driving a reflector includes a movement frame including a reflector configured to reflect or refract light to a lens and a first magnet, a first support frame configured to provide a space of the movement frame to move, a first drive coil configured to generate an electromagnetic force in the first magnet to rotationally move the movement frame in a first direction based on the first support frame, a first rotation guide between the movement frame and the first support frame and having an arc shape so that the movement frame rotates in the first direction, and a first ball inside the first rotation guide, in which a center of curvature of the first rotation guide corresponds to a center of rotation of the reflector.