Quantum Dot LCD Brightness via Sunlight Excitation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current liquid crystal display (LCD) devices experience low display brightness in outdoor settings due to intense outdoor light, which affects viewing quality, and the adoption of transflective display modes reduces the aperture ratio of pixel units.

Innovation Solution

Incorporating quantum dot (QD) layers that emit light after excitation by ultraviolet light in sunlight, enhancing display brightness and outdoor viewability by combining this light with the backlight through color filters, while using a high molecular polymer network to distribute QDs uniformly and prevent aggregation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Illumination intensity

If transflective display mode is adopted to brighten the LCD for outdoor display, then display brightness is improved, but aperture ratio of pixel units is reduced

Engineering Contradiction:
Improvedisplay brightnessVSAvoidaperture ratio of pixel units
Core Design Contradiction:
Illumination intensityVSArea of stationary object

Solution Approach 1:

The patent combines the backlight module with quantum dot layers that convert ultraviolet light to visible light, merging two light sources (backlight and sunlight-activated QD light) into a unified display system. This allows the display to benefit from both artificial backlighting and natural sunlight without requiring transflective mode, thereby maintaining high aperture ratio while achieving high brightness for outdoor viewing.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The quantum dot layers serve multiple functions: they act as a light conversion layer for the backlight module, and simultaneously serve as a photoluminescent layer that can be activated by ultraviolet light in sunlight. This multi-functionality allows the same structure to provide display enhancement in both indoor and outdoor conditions without compromising aperture ratio.

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

2Illumination intensity

If quantum dot layers are used to enhance outdoor brightness, then outdoor viewability is improved, but preparation process complexity increases

Engineering Contradiction:
Improveoutdoor display brightnessVSAvoidpreparation process complexity
Core Design Contradiction:
Illumination intensityVSDevice complexity

Solution Approach 1:

The quantum dot layers are integrated directly into the backlight module structure, merging the light conversion function with the existing display architecture. This consolidation eliminates the need for separate QD layer preparation processes and reduces overall system complexity while achieving enhanced outdoor brightness.

Inventive Principle:
Principle #5Merging (Combining)

3Use of energy by moving object

If quantum dot layers are used to emit light under sunlight excitation, then light utilization is improved, but uniform distribution of QDs becomes challenging

Engineering Contradiction:
Improvelight emission efficiencyVSAvoiduniform distribution of QDs
Core Design Contradiction:
Use of energy by moving objectVSStability of the object's composition

Solution Approach 1:

The patent introduces a resin layer as an intermediary medium that contains and distributes the quantum dot particles. This resin matrix acts as a carrier that ensures uniform dispersion of QDs throughout the layer, preventing aggregation and maintaining stable composition while enabling efficient light emission when excited by ultraviolet light from sunlight.

Inventive Principle:
Principle #24Intermediary (Mediator)

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 significantly improves display brightness and outdoor viewability by maximizing the utilization of light emitted by QD layers, reducing the complexity of the preparation process, and maintaining normal indoor display functionality.

Implementation Method 1

QD layers capable of allowing backlight to pass through are disposed at positions on the array substrate corresponding to the sub-pixel unit of at least one color in the pixel units. The QD layers are excited by ultraviolet light in sunlight and emit white light.

Methodology Applied
Scientific EffectPhotoluminescence: Photoluminescence

Data Source

PatentEP3026486B1Liquid crystal display screen and display device
Publication Date: 2019.09.11 BOE TECHNOLOGY GROUP CO LTD
  • EP3026486B1 patent drawingFigure 1a
  • EP3026486B1 patent drawingFigure 1b
  • EP3026486B1 patent drawingFigure 2a

AI summary

A liquid crystal display (LCD) and a display device are disclosed. The LCD is provided with a plurality of pixel units; each pixel unit comprises a plurality of sub-pixel units for displaying different colors; quantum dot (QD) layers (01) capable of allowing backlight to run through are disposed at positions of an array substrate (2), corresponding to the sub-pixel units of at least one color of the pixel units; the QD layers (01) are excited by ultraviolet light in sunlight and emit light which at least is of the color of the sub-pixel units; and color filters (02) are disposed between the QD layers (01) and the opposing substrate (1). The LCD has enhanced display brightness and higher outdoor viewability in the case of outdoor display.