Multilayer Actuator Coils for Precise Compact Camera Module Assembly

Solution Overview

Problem

Conventional coils for camera module actuators face challenges in precision manufacturing due to positional errors and increased rejection rates, particularly as camera modules shrink in size, making it difficult to accurately place and couple coils to flex or PCBs.

Innovation Solution

The solution involves manufacturing coils directly onto flex circuits and/or PCBs using additive manufacturing techniques, allowing for precise control over coil placement and electrical/mechanical coupling, and enabling the creation of smaller, more efficient coils.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If conventional coils are manufactured by winding wire around a mandrel and mechanically bonded to flex or PCB, then the manufacturing process is simple and well-established, but positional error increases and rejection rates increase

Engineering Contradiction:

Improvecoil placement precisionVSAvoidmanufacturing process complexity

Core Design Contradiction:

Manufacturing precisionVSEase of manufacture

Solution Approach 1:

The coil is manufactured directly onto the flex or PCB at its final destination position before assembly, eliminating subsequent positioning steps. The additive manufacturing process deposits conductive material layer-by-layer to form the coil trace precisely where needed on the substrate, ensuring accurate placement without mechanical bonding operations.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The mechanical winding and bonding process is replaced with additive manufacturing technology that deposits conductive material directly onto the flex or PCB. This substitution eliminates mechanical positioning errors and bonding variability, achieving higher precision through a non-mechanical deposition process.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

2Volume of moving object

If camera modules are shrunk in size, then the device becomes more compact and portable, but coil placement precision becomes more difficult to achieve

Engineering Contradiction:

Improvecamera module sizeVSAvoidcoil placement precision

Core Design Contradiction:

Volume of moving objectVSManufacturing precision

Solution Approach 1:

The coil is manufactured directly onto the flex or PCB at its final destination position before assembly, eliminating subsequent positioning steps. The additive manufacturing process deposits conductive material layer-by-layer to form the coil trace precisely where needed on the substrate, ensuring accurate placement without mechanical bonding operations.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The manufacturing approach changes from mechanical winding with fixed mandrel sizes to additive manufacturing with programmable deposition. This allows the coil dimensions and position to be precisely controlled through digital parameters, enabling accurate coil placement even in the reduced space of compact camera modules.

Inventive Principle:

Principle #35Parameter changes

3Reliability

If conventional coils are mechanically bonded to flex or PCB, then the assembly process is straightforward, but rejection rates increase due to positioning errors

Engineering Contradiction:

Improveassembly rejection rateVSAvoidmanufacturing process steps

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The coil manufacturing and substrate integration steps are merged into a single additive manufacturing process. The coil trace is deposited directly onto the flex or PCB, combining what were previously separate operations (coil winding, positioning, and bonding) into one integrated manufacturing step, thereby eliminating rejection sources.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The coil is manufactured directly onto the flex or PCB at its final destination position before assembly, eliminating subsequent positioning steps. The additive manufacturing process deposits conductive material layer-by-layer to form the coil trace precisely where needed on the substrate, ensuring accurate placement without mechanical bonding operations.

Inventive Principle:

Principle #10Preliminary action

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 approach reduces manufacturing complexities and rejection rates, enabling the production of smaller, high-performance coils that maintain equivalent or higher current-carrying capacity compared to traditionally manufactured coils.

Implementation Method 1

The coil may be positioned within a magnetic field originating from a nearby permanent magnet so as to leverage Lorenz force to effect movement as described above

Methodology Applied

Scientific EffectLorenz force: Lorentz Force

Data Source

PatentUS12266984B2Compact multilayer actuator coils for camera modules of portable electronic devices

Publication Date: 2025.04.01 APPLE INC

AI summary

A camera module for a portable electronic device includes an actuator assembly with at least one coil segment. The coil segment includes a dielectric substrate with two surfaces. Over each surface is formed a trace that follows a path defining a multi-turn coil. The coils of each side of the dielectric are conductively coupled together to define a single inductor/coil. The two-layer coil segment can be encapsulated as a component suitable for pick-and-place and/or SMT manufacturing. In many constructions, the actuator assembly includes a stack of coil segments, coupled together in series or parallel.