MEMS Micro-Mirror Assembly Flexible PCB Integration

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The integration of MEMS micro-mirror devices into projection systems is hindered by the fragility of wire bonds and electrical connectors, which can easily break during handling, making it difficult to achieve a stable and robust electrical connection.

Innovation Solution

A MEMS micro-mirror assembly is mounted on a flexible PCB board, where the MEMS die is mechanically connected using glue, and electrical connections are established through a combination of wire bonds and conductive glue, with multiple wire bonds providing increased mechanical stability and the flexible PCB board being reinforced in areas with conductive lines to prevent mechanical stress.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If wire bonds and electrical connectors are used to integrate MEMS micro-mirror devices into projection systems, then electrical connection is achieved, but the connection is fragile and prone to breakage during handling

Engineering Contradiction:
Improveelectrical connection stabilityVSAvoidmechanical strength of electrical connection
Core Design Contradiction:
ReliabilityVSStrength

Solution Approach 1:

The patent introduces a flexible PCB board as an intermediary component between the MEMS micro-mirror device and the projection system. This PCB board provides a robust mechanical support structure with integrated electrical traces that replace fragile wire bonds and connectors. The PCB board mechanically mounts the MEMS device while simultaneously providing stable electrical connections through its conductive pathways, thus resolving the contradiction between electrical connectivity and mechanical strength.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Reliability

If multiple wire bonds are used to provide increased mechanical stability, then electrical connection stability improves, but device complexity and manufacturing difficulty increase

Engineering Contradiction:
Improveelectrical connection stabilityVSAvoidcomplexity of electrical connection structure
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent merges the mechanical mounting function and the electrical connection function into a single integrated component - the flexible PCB board. Instead of using separate wire bonds and connectors that require multiple assembly steps, the PCB board combines structural support with integrated electrical traces, thereby reducing device complexity and manufacturing difficulty while maintaining reliable electrical connections.

Inventive Principle:
Principle #5Merging (Combining)

3Ease of manufacture

If the MEMS die is mechanically connected using glue, then assembly ease improves, but mechanical strength and reliability may be compromised

Engineering Contradiction:
Improveease of mechanical connectionVSAvoidstrength of mechanical connection
Core Design Contradiction:
Ease of manufactureVSStrength

Solution Approach 1:

The patent employs a composite mounting approach where the flexible PCB board itself acts as a composite structure providing both mechanical support and electrical connectivity. The PCB board's layered construction (combining flexible substrate with conductive traces) creates a robust mechanical connection that is stronger than glue alone, while the flexibility of the PCB material allows for ease of assembly and stress absorption during handling.

Inventive Principle:
Principle #40Composite materials

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 use of a flexible PCB board and robust electrical connections enables easier and more stable integration of MEMS micro-mirror assemblies into projection systems, reducing the risk of wire bond breakage and enhancing mechanical stability, thus facilitating reliable operation.

Implementation Method 1

the flexible PCB board being reinforced in areas with conductive lines to prevent mechanical stress

Methodology Applied
Scientific EffectMechanical reinforcement:

Implementation Method 2

electrical connections are established through a combination of wire bonds and conductive glue

Methodology Applied
Scientific EffectAdhesion: Adhesive

Data Source

PatentEP2823695B1A MEMS micro-mirror assembly
Publication Date: 2018.10.24 NORTH INC
  • EP2823695B1 patent drawingFigure 1a
  • EP2823695B1 patent drawingFigure 1b
  • EP2823695B1 patent drawingFigure 1c

AI summary

A MEMS micro-mirror assembly (250, 300, 270, 400) comprising, a MEMS device (240) which comprises a MEMS die (241) and a magnet (231); a flexible PCB board (205) to which the MEMS device (240) is mechanically, and electrically, connected; wherein the flexible PCB board (205) further comprises a first extension portion (205b) which comprises a least one electrical contact (259a,b) which is useable to electrically connect the MEMS micro-mirro rassembly (250, 300, 270, 400) to another electrical component). There is further provided a projection system comprising such a MEMS micro-mirror assembly (250, 300, 270, 400).