OLED Charge Generation Layer Microstructures for Voltage Reduction

Solution Overview

Problem

OLED devices in series face challenges with increased voltage and power consumption due to the use of a metal cathode, which affects light emission efficiency and color rendering, and the need for a charge generation layer that further elevates these issues.

Innovation Solution

Incorporating microstructures on at least one surface of the charge generation layer adjacent to the organic light emitting layers, either protruding or recessed, to increase the contact area and enhance charge generation and transfer capabilities, thereby reducing operating voltage and improving light emission efficiency.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If a charge generation layer is added to enable series connection in OLED devices, then the device can achieve series configuration, but the operating voltage and power consumption increase

Engineering Contradiction:

Improveseries connection capabilityVSAvoidpower consumption

Core Design Contradiction:

Adaptability or versatilityVSUse of energy by moving object

Solution Approach 1:

The charge generation layer is designed with localized microstructures (protrusions or recesses) at specific regions where charge generation is most needed, rather than uniformly across the entire layer. This localized structural modification optimizes charge generation efficiency at critical interfaces while minimizing the overall material usage and associated power consumption.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The invention introduces vertical dimensionality to the charge generation layer by creating protrusions or recesses, transforming it from a two-dimensional planar structure to a three-dimensional structured layer. This dimensional change increases the effective charge generation area and improves charge transfer efficiency, thereby reducing the voltage required for operation and lowering power consumption.

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

2Adaptability or versatility

If a charge generation layer is added to enable series connection in OLED devices, then the device can achieve series configuration, but the operating voltage increases

Engineering Contradiction:

Improveseries connection capabilityVSAvoidoperating voltage

Core Design Contradiction:

Adaptability or versatilityVSStress or pressure

Solution Approach 1:

The charge generation layer is designed with localized microstructures (protrusions or recesses) at specific regions where charge generation is most needed, rather than uniformly across the entire layer. This localized structural modification optimizes charge generation efficiency at critical interfaces while minimizing the overall material usage and associated power consumption.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The invention introduces vertical dimensionality to the charge generation layer by creating protrusions or recesses, transforming it from a two-dimensional planar structure to a three-dimensional structured layer. This dimensional change increases the effective charge generation area and improves charge transfer efficiency, thereby reducing the voltage required for operation and lowering power consumption.

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

3Productivity

If microstructures are added to the charge generation layer to increase contact area, then charge generation efficiency improves, but device complexity increases

Engineering Contradiction:

Improvecharge generation efficiencyVSAvoidstructure complexity

Core Design Contradiction:

ProductivityVSDevice complexity

Solution Approach 1:

The charge generation layer is segmented into multiple microstructures (protrusions or recesses) that are distributed across the layer. This segmentation increases the total surface area available for charge generation and transfer without requiring a complete redesign of the entire device architecture, thus improving efficiency while managing complexity through modular structural division.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The microstructures in the charge generation layer are designed with curved surfaces (spheroidal or rounded shapes) rather than sharp edges. This curvature increases the effective surface area for charge generation while distributing stress more evenly and simplifying the manufacturing process compared to complex angular structures, thereby improving charge generation efficiency without proportionally increasing device complexity.

Inventive Principle:

Principle #14Spheroidality (Curvature)

Data Source

PatentUS11108022B2OLED device, method for manufacturing the same, and display apparatus

Publication Date: 2021.08.31 BEIJING BOE TECH DEV CO LTD

AI summary

An OLED device, a method for manufacturing the same, and a display apparatus are provided. The OLED device includes: an anode; a cathode; at least two organic light emitting layers between the anode and the cathode; a charge generation layer between two adjacent organic light emitting layers. At least one of two surfaces of the charge generation layer adjacent to the two adjacent organic light emitting layers is provided with microstructures.