Free-Form Display Backlight Cavities for Borderless Light Uniformity

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Free-form display devices face challenges in achieving homogeneous illumination with matrix backlights, as the backlight often extends beyond the display area, leading to light leakage and the need for black printing, which conflicts with the goal of a borderless design.

Innovation Solution

A display device with a reflector having regularly shaped cavities in a grid and irregularly shaped cavities in edge regions, where light sources are arranged to match the free form of the panel, allowing for reduced installation space and adjustable brightness to ensure uniform illumination.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If a matrix backlight with regularly shaped grid-arranged cavities is used, then the installation space is sufficient and light sources can be evenly distributed, but the backlight extends beyond the display area causing light leakage and requiring black printing

Engineering Contradiction:
Improvelight source distributionVSAvoidlight leakage
Core Design Contradiction:
Ease of manufactureVSObject-generated harmful factors

Solution Approach 1:

The patent applies local quality by differentiating the cavity shapes based on their position: regularly shaped cavities in the central region and irregularly shaped cavities in the edge regions. This allows the backlight to adapt locally to the display panel's freeform shape, preventing light leakage at edges while maintaining even light source distribution in the center.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The reflector is segmented into different cavity types (regular and irregular shapes) arranged in a grid pattern. This segmentation allows different regions of the backlight to serve different functions: central regions provide uniform illumination while edge regions conform to the display boundaries, eliminating the need for black printing.

Inventive Principle:
Principle #1Segmentation

2Object-generated harmful factors

If black printing is used on the cover glass to prevent light leakage, then light leakage is prevented, but the borderless design is compromised

Engineering Contradiction:
Improvelight leakage preventionVSAvoidborderless design
Core Design Contradiction:
Object-generated harmful factorsVSShape

Solution Approach 1:

The patent implements preliminary action by pre-shaping the cavities in the reflector to match the display panel's freeform geometry before light emission occurs. The irregularly shaped cavities in edge regions are designed in advance to confine light within the display boundaries, eliminating the need for subsequent black printing and preserving the borderless design.

Inventive Principle:
Principle #10Preliminary action

3Shape

If irregularly shaped cavities are used in edge regions to match the display shape, then the borderless design is achieved and installation space is reduced, but homogeneous illumination becomes more difficult

Engineering Contradiction:
Improveborderless designVSAvoidillumination homogeneity
Core Design Contradiction:
ShapeVSIllumination intensity

Solution Approach 1:

The patent maintains illumination homogeneity through local quality by combining regular cavities in the center (for even light distribution) with irregular cavities at edges (for shape conformity). The regular central cavities ensure uniform light source spacing and intensity, while the irregular edge cavities adapt to the display boundaries without compromising overall homogeneity.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The backlight is segmented into central and edge regions with different cavity geometries. This segmentation allows each region to optimize its function: the central region prioritizes uniform illumination through regular cavities, while edge regions prioritize shape conformity through irregular cavities, achieving both homogeneity and borderless design.

Inventive Principle:
Principle #1Segmentation

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 provides more homogeneous illumination and reduces light leakage, enabling a borderless design by optimizing the reflector's cavity design and light source arrangement, ensuring consistent brightness across irregularly shaped display areas.

Implementation Method 1

a reflector with a plurality of regularly shaped and grid-arranged reflectively designed cavities

Methodology Applied
Scientific EffectReflection: Reflection

Implementation Method 2

a plurality of light sources arranged in the cavities

Methodology Applied
Scientific EffectLight emission: Light

Data Source

PatentEP4286929A1Display device and means of transportation
Publication Date: 2023.12.06 CONTINENTAL AUTOMOTIVE TECHNOLOGIES GMBH
  • EP4286929A1 patent drawingFigure 1~2
  • EP4286929A1 patent drawingFigure 3
  • EP4286929A1 patent drawingFigure 4

AI summary

The present invention relates to a display device (1) and a means of transportation with such a display device (1). The display device (1) comprises a display panel and a backlight (3) for the display panel. The backlight (3) comprises a reflector (30) with a plurality of regularly shaped, reflectively designed cavities (31) arranged in a grid. In at least one edge region (300), the reflector (30) has irregularly shaped, reflectively designed cavities (31'). Furthermore, the backlight (3) comprises a plurality of light sources (32, 32') arranged in the cavities (31).