Display Panel Defect Detection Using Multi-Color Illumination
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current defect detection methods for LCD display panels using white light often fail to detect defects that do not introduce an apparent grey-scale difference, leading to missed defects and reduced detection capability.
Innovation Solution
Utilizing a combination of red, green, and blue lights to illuminate the display panel, obtaining corresponding grey-scale diagrams, and determining defects based on grey-scale differences, with an optional white light step to confirm the absence of defects if no difference is indicated.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If white light is used to illuminate the display panel for defect detection, then the detection process is simple and fast, but defects that do not introduce apparent grey-scale difference cannot be detected
Solution Approach 1:
The detection process is segmented into multiple stages: first using white light for rapid screening, then using colored lights (red, green, blue) separately for detailed detection of specific defect types. This segmentation allows the system to maintain high productivity for common defects while ensuring high measurement precision for subtle defects through targeted colored light inspection.
Solution Approach 2:
The illumination parameter (light color) is changed from single white light to multiple colored lights. By changing the wavelength parameter of the illumination source, the system can reveal different types of defects that are not visible under white light, thereby improving defect detection accuracy without significantly reducing detection speed.
2Device complexity
If only grey-scale difference is used to determine defects, then the detection method is simple, but many defects are missed
Solution Approach 1:
The system uses color changes in illumination (white light, red light, green light, blue light) to reveal different types of defects. By changing the color parameter of the illumination source, defects such as pixel dropping, uneven distribution, water, or ITO remains become visible through grey-scale differences in the colored light images, significantly improving detection reliability while maintaining relatively simple detection methodology.
3Measurement precision
If multiple colored lights are used to illuminate the display panel, then defect detection accuracy is improved, but the detection process becomes more complex and time-consuming
Solution Approach 1:
The system performs preliminary defect screening using white light illumination first, which quickly identifies obvious defects. Only after this preliminary action does the system proceed to the more time-consuming colored light inspection for subtle defects. This preliminary action reduces the overall complexity by avoiding unnecessary colored light inspection for obviously defective panels.
Solution Approach 2:
Instead of always using all four colored lights for complete inspection, the system applies partial action by using colored lights only when needed based on preliminary white light screening results. This selective approach reduces detection process complexity and time while maintaining high accuracy for the defects that require colored light inspection.
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
Enhances the defect detection ability of display panels by identifying defects such as pixel dropping, uneven distribution, water, or ITO remains through grey-scale differences, preventing missed defects and improving detection accuracy.
Implementation Method 1
utilizing a red light, a green light, and a blue light to illuminate the display panel
Data Source
AI summary
The present invention provides a method for detecting a defect of a display panel and related defect detecting device. The method includes: utilizing lights having different colors to illuminate the display panel; obtaining a plurality of corresponding grey-scale diagrams when the lights illuminate the display panel; and determining whether the display panel has a defect. If the grey-scale diagrams indicate a grey-scale difference, determining that the display panel has a defect. In this way, the present invention is able to raise defect detecting ability for the display panel and prevent from missing the defects.