Display Device Inspection Element for Injection-Dependent Compensation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for driving light-emitting elements, such as those in display devices, are ineffective when light-emission characteristics heavily depend on electron injection or hole injection.
Innovation Solution
A display device configuration that includes a light-emitting element with specific electrode and charge transport layer structures, and a shared first inspection element with an electron-only device (EOD) or hole-only device (HOD) configuration, allowing the light-emitting element to be driven based on the characteristics of the inspection element.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If external compensation method is used for light-emitting elements with electron injection or hole injection dependence, then light-emission characteristics can be controlled, but the method is ineffective when characteristics heavily depend on electron injection or hole injection
Solution Approach 1:
The light-emitting element is divided into functional sub-layers including electron transport layer, hole transport layer, and light-emitting layer. Inspection elements are separately formed for each charge type (electron-only and hole-only), allowing independent measurement of electron and hole injection characteristics. This segmentation enables targeted compensation for each charge carrier type that previously limited the effectiveness of external compensation methods.
2Ease of manufacture
If inspection elements share light-emitting layer and charge transport layers with light-emitting elements, then manufacturing complexity is reduced, but measurement precision may be affected
Solution Approach 1:
While sharing common layers (light-emitting layer, electron transport layer, hole transport layer) ensures manufacturing consistency, the inspection elements are locally modified with specific electrode configurations. Electron-only inspection elements use a structure optimized for electron injection measurement, while hole-only inspection elements use a structure optimized for hole injection measurement. This local differentiation maintains measurement precision for each charge type while preserving the manufacturing advantages of shared layers.
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 external compensation for light-emitting elements with emission characteristics heavily dependent on electron or hole injection, reducing variations in subpixel characteristics and improving overall image quality.
Implementation Method 1
a first charge transport layer provided between the first electrode and the light-emitting layer, and a second charge transport layer provided between the light-emitting layer and the second electrode
Implementation Method 2
a light-emitting element including, for each subpixel, a first electrode, a second electrode, a light-emitting layer provided between the first electrode and the second electrode
Data Source
AI summary
A display device including a light-emitting element including a first electrode, a second electrode, a light-emitting layer, a first charge transport layer having a function of transporting first charge, and a second charge transport layer having a function of transporting second charge, in which the display device includes a first inspection element including a fourth electrode and a third electrode. The first inspection element is a single-charge element including the light-emitting layer and the first charge transport layer that are common to the light-emitting element and making mainly the first charge flow, and the light-emitting element is driven in accordance with characteristics of the first inspection element.