Light Emitting Display Layout With Shielded Transistor Regions

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing display devices face challenges in improving brightness and reliability, particularly in preventing the influence of light on transistors due to mixed light emitting and transmitting portions, and internal scattering, which affects transistor performance and efficiency.

Innovation Solution

A light emitting display device with a light shielding pixel-defining film around light emitting portions and a structured light transmitting portion, using high-mobility oxide semiconductors to manage light transmission and reflection, and optimizing manufacturing processes to reduce material usage and greenhouse gas emissions.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a light shielding pixel-defining film is disposed around light emitting portions, then light transmission to transistors is blocked improving reliability, but device complexity increases

Engineering Contradiction:
Improvetransistor performance stabilityVSAvoidstructure complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

A light shielding pixel-defining film is introduced as an intermediary component between the light emitting portion and the transistor. This film selectively blocks light from reaching the transistor while allowing other functions to proceed normally, thus resolving the contradiction by adding a dedicated light-blocking layer that prevents light-induced performance degradation without fundamentally redesigning the entire device structure.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The pixel structure is segmented into distinct functional regions: a light emitting portion, a light transmitting portion, and a light shielding region. The pixel-defining film is divided into a light emitting portion pixel-defining film and a light transmitting portion pixel-defining film with different optical properties. This segmentation allows each region to be optimized independently, improving reliability through targeted light management while keeping the overall structure manageable.

Inventive Principle:
Principle #1Segmentation

2Ease of manufacture

If the light shielding pixel-defining film has uniform thickness, then manufacturing is simplified, but brightness uniformity deteriorates due to rapid changes at boundaries

Engineering Contradiction:
Improvemanufacturing simplicityVSAvoidbrightness uniformity
Core Design Contradiction:
Ease of manufactureVSIllumination intensity

Solution Approach 1:

The pixel-defining film exhibits local quality variations in its thickness profile. At the boundary between light emitting and light transmitting portions, the film thickness gradually transitions rather than changing abruptly. This gradual thickness change creates a smooth optical transition zone that prevents rapid brightness changes and maintains brightness uniformity, while the overall manufacturing process remains relatively simple.

Inventive Principle:
Principle #3Local quality

3Productivity

If high-mobility oxide semiconductors are used in transistors, then transistor efficiency improves, but sensitivity to light influence increases worsening reliability

Engineering Contradiction:
Improvetransistor efficiencyVSAvoidlight sensitivity
Core Design Contradiction:
ProductivityVSReliability

Solution Approach 1:

The high-mobility oxide semiconductor transistor, which is inherently more sensitive to light, is paired with an enhanced light shielding pixel-defining film structure. The harm of increased light sensitivity is converted into a benefit by demonstrating that with proper light shielding design, even more sensitive materials can be used to achieve higher efficiency. The light shielding film effectively neutralizes the negative effect, allowing the transistor's high efficiency to be fully realized.

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

Enhances brightness and reliability by shielding light, maintaining transistor performance, and optimizing manufacturing processes to improve optical efficiency and reduce environmental impact.

Implementation Method 1

a light shielding pixel-defining film provided at the first area, exposing a first blue light emitting portion, a first green light emitting portion, and a first red light emitting portion

Methodology Applied
Scientific EffectLight shielding: Absorption (EM radiation)

Implementation Method 2

a light emitting element on the first blue light emitting portion, the first green light emitting portion, and the first red light emitting portion

Methodology Applied
Scientific EffectLight emission: Electroluminescence

Data Source

PatentEP4611514A1Light emitting display device
Publication Date: 2025.09.03 LG DISPLAY CO LTD
  • EP4611514A1 patent drawingFigure 1
  • EP4611514A1 patent drawingFigure 2
  • EP4611514A1 patent drawingFigure 3

AI summary

Disclosed is a light emitting display device including a substrate including a first area and a second area, a first light shielding pixel-defining film provided in the first area, exposing a first blue light emitting portion, a first green light emitting portion, and a first red light emitting portion, and having a first height, a second light shielding pixel-defining film provided in the second area, including a region exposing a second blue light emitting portion, a second green light emitting portion, and a second red light emitting portion and a light transmitting portion, and including an area having a second height smaller than the first height, and a light emitting element provided on the first blue light emitting portion, the first green light emitting portion, the first red light emitting portion, the second blue light emitting portion, the second green light emitting portion, and the second red light emitting portion.