Reflective Display Panel Micro-Slits for Lower Light Leakage

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Solution Overview

Problem

Reflective display panels face issues with light leakage and poor display contrast due to manufacturing process factors, particularly in dark-state modes, which are exacerbated by the use of high-reflectivity metal materials.

Innovation Solution

The display panel incorporates reflective patterns divided into multiple reflective portions by micro-slits, reducing the reflection area and minimizing light leakage, thereby improving display contrast and brightness uniformity.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Illumination intensity

If the reflective layer is made of high-reflectivity metal material and its distribution range is increased, then reflection efficiency is improved, but light leakage problem is highlighted resulting in poor display contrast

Engineering Contradiction:
Improvereflection efficiencyVSAvoidlight leakage
Core Design Contradiction:
Illumination intensityVSObject-affected harmful factors

Solution Approach 1:

The reflective layer is segmented into multiple isolated reflective islands instead of a continuous layer. Each pixel electrode is surrounded by multiple reflective islands that are electrically isolated from each other, preventing light leakage while maintaining reflection efficiency. The segmentation is achieved by forming reflective islands through a multi-step sputtering process with selective masking.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The reflective layer has different properties in different locations: reflective islands are positioned close to pixel electrodes to provide local reflection enhancement, while the spaces between islands remain non-reflective to prevent light leakage. This local differentiation allows simultaneous optimization of reflection efficiency and contrast ratio.

Inventive Principle:
Principle #3Local quality

2Illumination intensity

If the reflective layer distribution range is increased as much as possible, then reflection efficiency is improved, but manufacturing precision requirements are exacerbated due to light leakage issues

Engineering Contradiction:
Improvereflection efficiencyVSAvoidpositioning precision
Core Design Contradiction:
Illumination intensityVSManufacturing precision

Solution Approach 1:

The continuous reflective layer is divided into discrete reflective islands, each positioned with precise control relative to pixel electrodes. This segmentation relaxes manufacturing precision requirements by allowing independent positioning of each island rather than requiring perfect uniformity across a continuous layer.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

An organic insulating layer is introduced as an intermediary between the reflective islands and the pixel electrodes. This intermediary layer provides both electrical insulation and precise thickness control (50-150 nm), enabling accurate positioning of reflective islands relative to pixel electrodes while preventing direct contact and light leakage.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Illumination intensity

If high-reflectivity metal material is used in the reflective layer, then reflection efficiency is improved, but dark-state brightness increases resulting in poor display contrast

Engineering Contradiction:
Improvereflection efficiencyVSAvoiddark-state brightness
Core Design Contradiction:
Illumination intensityVSObject-generated harmful factors

Solution Approach 1:

The reflective layer is segmented into isolated islands rather than a continuous layer. This segmentation prevents the formation of continuous light leakage paths in the dark state, reducing dark-state brightness while maintaining high reflection efficiency during display operation through the use of high-reflectivity metal materials in the islands.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The potential harm of high-reflectivity metal materials causing light leakage is converted into a benefit by using the same materials to create discrete reflective islands. The high reflectivity is beneficial for display brightness, while the discrete island structure eliminates the harmful light leakage effect.

Inventive Principle:
Principle #22Blessing in disguise (Convert harm into benefit)

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 micro-slit design effectively reduces dark-state brightness and enhances display contrast and brightness uniformity without significantly affecting overall reflectivity.

Implementation Method 1

a liquid crystal layer disposed between the first substrate and the second substrate

Methodology Applied
Scientific EffectLiquid crystal effect: Liquid Crystals

Implementation Method 2

the reflective patterns are respectively arranged at intervals along a first direction and a second direction... Each of the reflective patterns has a first side edge and a second side edge arranged along the first direction

Methodology Applied
Scientific EffectLight reflection: Reflection

Data Source

PatentEP4603899B1Display panel
Publication Date: 2026.03.18 HANNSTAR DISPLAY CORP
  • EP4603899B1 patent drawingFigure 1
  • EP4603899B1 patent drawingFigure 2
  • EP4603899B1 patent drawingFigure 3

AI summary

A display panel (10) including a first substrate (101), a second substrate (102), a plurality of pixel structures (PX) and a liquid crystal layer (LCL) is provided. The first substrate (101) and the second substrate (102) are overlapped with each other. The pixel structures (PX) are disposed on the first substrate (101) and respectively provided with a plurality of reflective patterns (RP). Each of the reflective patterns (RP) is divided into a plurality of reflective portions (RPp) by a plurality of micro-slits (SLT1, SLT2). The reflective portions (RPp) are connected to each other. The liquid crystal layer (LCL) is disposed between the first substrate (101) and the second substrate (102).