Display Device Sub-Pixel Segmentation for Color Shift Prevention

Solution Overview

Problem

Active matrix driving methods for light-emitting components face challenges in achieving high luminance grey levels without significant color shift, leading to poor picture quality due to the need for small currents to drive low brightness levels.

Innovation Solution

The implementation of a display device with sub-pixels containing multiple independently illuminated light-emitting units, each comprising several illumination portions, where driving units adjust current amplitudes and duty ratios to express various grey levels, allowing for flexible control of brightness without relying on low currents.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If the light-emitting component is driven by a small current to present low brightness grey levels, then the number of luminance grey levels can be increased, but the light emitted undergoes significant color shift resulting in poor picture quality

Engineering Contradiction:

Improvenumber of luminance grey levelsVSAvoidcolor shift

Core Design Contradiction:

Adaptability or versatilityVSObject-affected harmful factors

Solution Approach 1:

The light-emitting component is divided into multiple illumination portions (first illumination portion, second illumination portion, etc.) that can be independently controlled. Each illumination portion is driven by separate driving units with independent current control, allowing different illumination portions to operate at different current levels without causing color shift in the overall display output.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different illumination portions are assigned different driving currents based on local requirements. The first illumination portion receives a first driving current while the second illumination portion receives a second driving current, allowing each region to be optimized for its specific brightness requirements without compromising color stability across the entire display.

Inventive Principle:

Principle #3Local quality

2Illumination intensity

If the active matrix driving method uses different current sizes to drive light emitting components, then the light emitting component can emit light of different brightness, but driving with small currents causes significant color shift

Engineering Contradiction:

ImprovebrightnessVSAvoidcolor shift

Core Design Contradiction:

Illumination intensityVSObject-affected harmful factors

Solution Approach 1:

The light-emitting component is divided into multiple illumination portions (first illumination portion, second illumination portion, etc.) that can be independently controlled. Each illumination portion is driven by separate driving units with independent current control, allowing different illumination portions to operate at different current levels without causing color shift in the overall display output.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different illumination portions are assigned different driving currents based on local requirements. The first illumination portion receives a first driving current while the second illumination portion receives a second driving current, allowing each region to be optimized for its specific brightness requirements without compromising color stability across the entire display.

Inventive Principle:

Principle #3Local quality

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

This approach enables the display device to present a large number of grey levels in different frames while preventing color shift issues, thereby improving picture quality and extending the service life of light-emitting components.

Implementation Method 1

each pixel in the active matrix can be driven continuously and independently, and driving signal of each pixel can be recorded without using a high pulse current for a long time to drive each pixel

Methodology Applied

Scientific EffectElectroluminescence: Electroluminescence

Data Source

PatentUS20210012703A1Display device

Publication Date: 2021.01.14 INNOLUX CORP

AI summary

A method for expressing a grey level of a sub-pixel in a display device includes providing at least one light emitting unit in the sub-pixel, the light emitting unit including a plurality of illumination portions, and illuminating at least one of the plurality of illumination portions to express the grey level of the sub-pixel, and each illumination portion is illuminated independently.