MEMS Display Auto-Inspection Mechanism for Pixel Defect Detection

Solution Overview

Problem

High-definition display devices with large numbers of pixels, such as HDTV and 4K displays, face challenges in inspecting millions of pixels effectively due to the complexity of visual inspection systems requiring dark rooms, high-resolution vision, and human operation, making it difficult to identify and address defective pixels.

Innovation Solution

A MEMS display device with an integrated auto-inspection mechanism that applies a test voltage between the movable element and the stopper to detect leak current, allowing for the identification of defective pixels and enabling automatic testing, thereby improving yield and reducing manual inspection reliance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If visual inspection systems are used to check pixels, then inspection capability is provided, but the system requires dark rooms, high-resolution vision systems, complicated software, and human operators, increasing system complexity and operational difficulty

Engineering Contradiction:

Improvepixel inspection capabilityVSAvoidinspection system complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The MEMS device performs self-inspection by utilizing its own operational components (movable element, stopper, and electrical connections) to detect defects. The device applies test voltages to itself and monitors for leak currents, eliminating the need for external complex visual inspection systems and human operators.

Inventive Principle:

Principle #25Self-service

Solution Approach 2:

The patent replaces complex mechanical/optical visual inspection systems with a simple electrical measurement system. Instead of using high-resolution vision systems and complicated software, the invention uses electrical voltage application and current monitoring to detect pixel defects, significantly simplifying the inspection mechanism.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

2Reliability

If visual inspection systems are used to check pixels, then inspection capability is provided, but human operators are required for final visual checks, increasing operational complexity and time consumption

Engineering Contradiction:

Improvepixel inspection capabilityVSAvoidinspection operation simplicity

Core Design Contradiction:

ReliabilityVSEase of operation

Solution Approach 1:

The MEMS device performs self-inspection by utilizing its own operational components (movable element, stopper, and electrical connections) to detect defects. The device applies test voltages to itself and monitors for leak currents, eliminating the need for external complex visual inspection systems and human operators.

Inventive Principle:

Principle #25Self-service

Solution Approach 2:

The inspection mechanism uses feedback from electrical measurements (leak current detection) to automatically identify defective pixels. The system continuously monitors electrical parameters and provides immediate feedback on pixel status, replacing manual visual checks with automated electrical sensing.

Inventive Principle:

Principle #23Feedback

3Reliability

If manual visual inspection is used, then pixel defects can be identified, but the process is time-consuming and reduces productivity

Engineering Contradiction:

Improvedefective pixel identificationVSAvoidinspection speed

Core Design Contradiction:

ReliabilityVSProductivity

Solution Approach 1:

The patent replaces complex mechanical/optical visual inspection systems with a simple electrical measurement system. Instead of using high-resolution vision systems and complicated software, the invention uses electrical voltage application and current monitoring to detect pixel defects, significantly simplifying the inspection mechanism.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The inspection process can be performed continuously during device operation or manufacturing without interruption. The electrical measurement system allows for real-time monitoring of pixel status, enabling continuous inspection rather than discrete manual checks, thereby improving productivity.

Inventive Principle:

Principle #20Continuity of useful 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

The auto-inspection mechanism effectively identifies defective pixels, enhancing the efficiency of the inspection process and improving yield by providing precise addresses of faulty pixels, which can be used for quality control and real-time monitoring in manufacturing and operational settings.

Implementation Method 1

an auto-inspection mechanism that applies a test voltage between the movable element and the stopper and determines whether or not a leak current is present

Methodology Applied

Scientific EffectElectrical conduction: Conduction (electrical)

Data Source

PatentUS11482143B2MEMS display device with auto-inspection mechanism

Publication Date: 2022.10.25 SA IGNITE INC

AI summary

A Micro-Electro-Mechanical Systems (MEMS) device includes a substrate, an electronic circuit mounted on the substrate, a movable element mounted on the substrate whose movement is controlled by application of an operating voltage by the electronic circuit, a stopper mounted on the substrate that stops the movement of the movable element through mechanical contact of the stopper with the movable element, and an auto-inspection mechanism that applies a test voltage between the movable element and the stopper and determines whether or not a leak current is present. The auto-inspection mechanism is mounted, at least in part, on the substrate. The test voltage is lower than the operating voltage.