Display Apparatus Optical Compensation Layer Viewing Angle Control

Solution Overview

Problem

Display apparatuses with light-blocking patterns to restrict light travel direction suffer from Moire and degraded image quality due to bright external light, particularly when viewed at narrow angles.

Innovation Solution

A display apparatus comprising a device substrate with a light-emitting device, encapsulation unit, anti-reflection layer, linear polarizer, and dichroic dye layer, along with optical compensation layers to control light direction and absorption, preventing Moire and enhancing viewing angle characteristics.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If a light control film with light-blocking patterns is used to restrict light traveling direction, then the viewing angle is narrowed, but Moire and spot occur due to the patterns degrading image quality

Engineering Contradiction:

Improveviewing angle controlVSAvoidimage quality

Core Design Contradiction:

Adaptability or versatilityVSManufacturing precision

Solution Approach 1:

The patent extracts and removes the light-blocking patterns from the light control film, replacing them with a directional light emission structure at the pixel level. This eliminates the Moire and spot issues caused by patterns while maintaining viewing angle control through the intrinsic directional emission characteristics of the pixel structure.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

Instead of using a film to block and restrict light directions (negative approach), the patent inverts the approach by designing the pixel structure itself to emit light directionally (positive approach). This inversion eliminates the need for patterned blocking films that cause Moire effects.

Inventive Principle:

Principle #13The other way round (Inversion)

2Adaptability or versatility

If a light control film with light-blocking patterns is used to restrict light traveling direction, then the viewing angle is narrowed, but the quality of the image realized is degraded

Engineering Contradiction:

Improveviewing angle controlVSAvoidimage quality

Core Design Contradiction:

Adaptability or versatilityVSReliability

Solution Approach 1:

The patent extracts and removes the light-blocking patterns from the light control film, replacing them with a directional light emission structure at the pixel level. This eliminates the Moire and spot issues caused by patterns while maintaining viewing angle control through the intrinsic directional emission characteristics of the pixel structure.

Inventive Principle:

Principle #2Taking out (Extraction)

3Adaptability or versatility

If light-blocking patterns are used to control light direction, then viewing angle is restricted, but Moire occurs particularly when viewed at narrow angles

Engineering Contradiction:

Improveviewing angle restrictionVSAvoidMoire

Core Design Contradiction:

Adaptability or versatilityVSObject-generated harmful factors

Solution Approach 1:

The patent extracts and removes the light-blocking patterns from the light control film, replacing them with a directional light emission structure at the pixel level. This eliminates the Moire and spot issues caused by patterns while maintaining viewing angle control through the intrinsic directional emission characteristics of the pixel structure.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

Instead of using a film to block and restrict light directions (negative approach), the patent inverts the approach by designing the pixel structure itself to emit light directionally (positive approach). This inversion eliminates the need for patterned blocking films that cause Moire effects.

Inventive Principle:

Principle #13The other way round (Inversion)

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 restricts the viewing angle and prevents Moire, improving image quality by controlling light direction and absorption, ensuring the display remains clear and vibrant even in bright external light conditions.

Implementation Method 1

A linear polarizer is disposed between the anti-reflection layer and the dichroic dye layer

Methodology Applied

Scientific EffectPolarisation: Polarisation

Implementation Method 2

The dichroic dye layer includes dyes vertically arranged

Methodology Applied

Scientific EffectAbsorption (EM radiation): Absorption (EM radiation)

Implementation Method 3

A dichroic dye layer is disposed on the anti-reflection layer

Methodology Applied

Scientific EffectDichroic Filter: Dichroic Filter

Implementation Method 4

An anti-reflection layer is disposed on the encapsulation unit

Methodology Applied

Scientific EffectAnti-Reflective Coating: Anti-Reflective Coating

Implementation Method 5

A first optical compensation layer is disposed between the linear polarizer and the dichroic dye layer

Methodology Applied

Scientific EffectBirefringence: Birefringence

Data Source

PatentUS20240219606A1Display apparatus having a light-emitting device

Publication Date: 2024.07.04 LG DISPLAY CO LTD

AI summary

Discussed is a display apparatus that can include an encapsulation unit covering a light-emitting device and an optical unit on the encapsulation unit. The optical unit can control viewing angle of the light emitted from the light-emitting device. For example, the optical unit can include a linear polarizer, a dichroic dye layer disposed on the linear polarizer and an optical compensation layer disposed between the linear polarizer and the dichroic dye layer. Thus, in the display apparatus, the viewing angle of the dichroic dye layer can be compensated by an in-plane phase retardation value (Rin) and/or a thickness direction phase retardation value (Rth) according to a type of the optical compensation layer.