Light Absorbing Layer for Display Brightness Uniformity

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Display devices with passive light-emitting panels face challenges in achieving pure black screens due to light leakage from the backlight unit and suffer from mura (stains) and non-uniform brightness, affecting color reproducibility.

Innovation Solution

Incorporating a light absorbing material in a light absorbing layer that absorbs light in specific wavelengths, enhancing the display device's ability to achieve black screens, reduce mura, and improve brightness uniformity by using a structure with a light absorbing layer comprising a first and second resin layer and light absorbers arranged in grooves on the first resin layer.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Illumination intensity

If a backlight unit is always turned on to supply light to the display panel, then the display device can function properly, but light leaks out causing difficulty in realizing pure black screens

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

Solution Approach 1:

A light absorbing layer is introduced as an intermediary component between the backlight unit and the display panel. This layer selectively absorbs leaked light while allowing necessary light to pass through, thereby preventing light leakage without compromising the backlight unit's continuous operation

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The light absorbing layer is positioned specifically at locations where light leakage occurs, such as around the edges of the display panel. This localized approach absorbs harmful light in specific areas while maintaining overall brightness uniformity across the display

Inventive Principle:
Principle #3Local quality

2Object-affected harmful factors

If a light absorbing layer is added to prevent light leakage, then black screen quality improves, but device complexity increases

Engineering Contradiction:
Improvelight leakageVSAvoidstructure
Core Design Contradiction:
Object-affected harmful factorsVSDevice complexity

Solution Approach 1:

The light absorbing layer is integrated with existing display components such as the bezel or edge frame structure. By merging the light absorption function with existing structural elements, the patent prevents light leakage without significantly increasing device complexity

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The light absorbing layer serves multiple functions: it absorbs leaked light to improve black screen quality, maintains brightness uniformity, and can be integrated with structural components. This multi-functionality reduces the need for additional separate components

Inventive Principle:
Principle #6Universality (Multi-functionality)

3Manufacturing precision

If light absorbing material is added to the light absorbing layer, then mura and brightness uniformity improve, but manufacturing complexity increases

Engineering Contradiction:
Improvebrightness uniformityVSAvoidmanufacturing
Core Design Contradiction:
Manufacturing precisionVSEase of manufacture

Solution Approach 1:

The patent optimizes parameters such as the thickness of the light absorbing layer, the concentration and type of light absorbing material, and the layer's position relative to the backlight unit. By carefully controlling these parameters, the patent achieves uniform brightness and eliminates mura while maintaining manufacturability

Inventive Principle:
Principle #35Parameter changes

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 solution effectively reduces or prevents mura, enhances color reproducibility, and achieves uniform brightness by absorbing unnecessary light, thereby improving the overall image quality of the display device.

Implementation Method 1

adding a light absorbing material that absorbs light in a particular wavelength range to a light absorbing layer

Methodology Applied
Scientific EffectLight absorption: Absorption (EM radiation)

Data Source

PatentEP3673330B1Display device
Publication Date: 2022.11.30 SAMSUNG ELECTRONICS CO LTD
  • EP3673330B1 patent drawingFigure 1~2
  • EP3673330B1 patent drawingFigure 3
  • EP3673330B1 patent drawingFigure 4~5

AI summary

Provided is a display device with enhanced uniformity of brightness. The display device includes a display panel, and a backlight unit configured to supply light to the display panel, wherein the display panel includes a liquid crystal panel with first and second surfaces opposite to each other, a first polarizing plate arranged on the first surface of the liquid crystal panel, a second polarizing plate arranged on the second surface of the liquid crystal panel, a light absorbing layer arranged on the second polarizing plate to absorb a portion of the light supplied from the backlight unit, and a light absorbing material included in the light absorbing layer to absorb light of particular wavelengths.