OLED Aperture Ratio via Overlapping Resistor and Power Lines
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The overall aperture ratio of organic light emitting devices is reduced due to the presence of resistors, which limit current and affect light transmittance in large-area devices.
Innovation Solution
The design includes a resistor line and power line with an overlapping area of 60 to 100%, where the resistor line is electrically connected to the first electrode layer and partially overlaps with the power line, which is opaque, using an insulation layer with a contact hole for connection, thereby minimizing the impact of the resistor on aperture ratio and light transmittance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a resistor is disposed in each light emitting unit to limit current during short circuit, then the reliability of the organic light emitting device is improved, but the overall aperture ratio is reduced
Solution Approach 1:
The resistor line is merged with the power line by positioning them to overlap, forming a combined structure where the power line serves dual functions: power transmission and current limiting. This integration eliminates the need for separate resistor components, thereby maintaining reliability while improving aperture ratio.
Solution Approach 2:
The patent transitions from a planar layout where resistor and power line are separate to a three-dimensional overlapping configuration. The resistor line is positioned to overlap with the power line in the vertical dimension, allowing electrical connection through contact holes in the insulation layer, thus reducing horizontal space occupation.
2Ease of manufacture
If the resistor line is disposed separately from the power line, then the electrical connection is simplified, but the light transmittance and aperture ratio are reduced
Solution Approach 1:
The resistor line and power line are merged into a single overlapping structure, where the power line provides both power transmission and current limiting functions. This reduces the number of separate components and improves light transmittance while maintaining electrical connection through contact holes.
Solution Approach 2:
The insulation layer with contact holes acts as an intermediary structure that enables electrical connection between the overlapping resistor line and power line. This mediator allows the lines to be positioned in overlapping configuration without direct contact, maintaining both electrical functionality and optical performance.
Data Source
AI summary
An organic light emitting device having light emitting units on a substrate is provided. Each light emitting unit includes a first electrode layer, an organic light emitting layer, a second electrode layer, a power line, a resistor line, an insulating layer. The first electrode layer is disposed on the substrate. The organic light emitting layer is disposed on the first electrode layer. The second electrode layer is disposed on the organic light emitting layer. The power line is disposed on the substrate. The resistor line is electrically connected to the first electrode layer, wherein the resistor line partially overlaps with the power line, and an overlapping area occupies 60˜100% of a total area of the resistor line. The insulating layer is disposed between the power line and the resistor line, and a contact hole is disposed in the insulating layer to electrically connect the power line and the resistor line.