Continuous LCD Polarizer Lamination with Defect Marking

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The existing manufacturing process for liquid-crystal display elements faces challenges in detecting defects in polarizing composite films, leading to reduced production efficiency and accuracy, as it is difficult to produce defect-free continuous optical film laminates, resulting in defective products and increased manufacturing complexity.

Innovation Solution

A method and system that continuously feed an optical film laminate with marked defects, allowing only defect-free sheets to be laminated onto liquid-crystal panels by detecting marks indicating defect positions and forming slit lines to separate normal and defective regions, ensuring only defect-free sheets are used for lamination.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If continuous web of optical film laminate is used for manufacturing liquid-crystal display elements, then productivity is improved, but manufacturing precision deteriorates due to difficulty in detecting and avoiding defects in the polarizing composite film

Engineering Contradiction:
Improvemanufacturing speedVSAvoiddefect detection accuracy
Core Design Contradiction:
ProductivityVSManufacturing precision

Solution Approach 1:

The patent applies preliminary action by providing mark information indicating defect positions on the continuous web of optical film laminate before the lamination process. This allows the system to pre-identify defective regions and plan the lamination path to avoid them, thereby maintaining high manufacturing precision while achieving continuous high-speed production.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent introduces mark information as an intermediary element that carries defect position data on the continuous web. This intermediary enables the lamination apparatus to detect and respond to defects without interrupting the continuous feed, thus resolving the contradiction between continuous production and defect avoidance.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Reliability

If defect-free sheets are selected from continuous web for lamination, then product accuracy is improved, but device complexity increases due to need for defect detection and sheet selection mechanisms

Engineering Contradiction:
Improveproduct accuracyVSAvoidmanufacturing process complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent uses mark information as a copy or representation of defect positions rather than requiring direct inspection of each sheet during lamination. This copying approach simplifies the device by replacing complex real-time inspection systems with a simpler mechanism that reads pre-provided mark information, thereby reducing device complexity while maintaining product accuracy.

Inventive Principle:
Principle #26Copying

3Adaptability or versatility

If polarizing composite film sheets are cut from continuous web at 45 degrees orientation, then adaptability to TN-type liquid-crystal panels is improved, but manufacturing precision deteriorates due to alignment difficulties

Engineering Contradiction:
Improvecompatibility with TN-type LCDVSAvoidalignment precision
Core Design Contradiction:
Adaptability or versatilityVSManufacturing precision

Solution Approach 1:

The patent applies local quality by providing mark information at specific locations on the continuous web that indicates defect positions. This localized information allows the system to maintain the required 45-degree orientation for TN-type LCD compatibility while precisely controlling where cuts are made to avoid defects, thereby resolving the alignment precision issue.

Inventive Principle:
Principle #3Local quality

Data Source

PatentEP2325007B1Method and system for continuously manufacturing liquid-crystal display element
Publication Date: 2011.11.16 NITTO DENKO CORP
  • EP2325007B1 patent drawingFigure 1
  • EP2325007B1 patent drawingFigure 2
  • EP2325007B1 patent drawingFigure 3

AI summary

The present invention provides a method for continuously manufacturing liquid-crystal display elements by laminating sheets of polarizing composite film (10) to respective ones of a plurality of liquid-crystal panels, the sheet being formed by cutting a continuous web of an optical film laminate having a width corresponding to a long or short side of the liquid crystal panel. The method comprises steps of; continuously feeding an optical film laminate (10), calculating a length measurement data based on the feed length of the optical film laminate, detecting a mark provided to the optical film laminate indicating defect information in a polarizing composite film being detected in a preliminary inspection, sequentially forming slit lines in a transverse direction with respect to the feed direction of the optical film laminate, determining the polarizing composite film sheet separated by the respective slit lines is a defective polarizing sheet or a normal polarizing sheet, peeling a sheet determined to be a normal polarizing sheet from the carrier film, and laminating the normal polarizing sheet to a respective one of liquid-crystal panel.