OLED Storage Capacitor Vertical Integration Aperture Ratio
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In OLED display panels, especially bottom emission and double-sided emission types, the integration of a storage capacitor reduces the effective light emitting area, leading to a small aperture ratio and complicates the process of adding touch sensing elements.
Innovation Solution
Incorporating a capacitor dielectric layer within the subpixel, with the storage capacitor located between two substrates, and designing self-capacitance or mutual-capacitance sensing electrodes to be formed simultaneously with the patterned conductive layers, allowing for touch control and display functions while minimizing process complexity and cost.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If a storage capacitor is disposed in bottom emission or double-sided emission OLEDs, then the storage capacitor area is sufficient, but the effective light emitting area becomes very small resulting in a small aperture ratio
Solution Approach 1:
The patent moves the storage capacitor from the planar substrate level to the vertical dimension by forming it between the first substrate and second substrate. The capacitor dielectric layer is positioned in the spacing between substrates, allowing the capacitor to occupy vertical space rather than horizontal display area, thus preserving the aperture ratio while maintaining sufficient capacitor area.
2Adaptability or versatility
If an extra touch sensing element is designed inside an OLED, then touch sensing function is provided, but the process becomes more complex and the aperture ratio becomes smaller
Solution Approach 1:
The patent combines the touch sensing electrode with the capacitor electrode structure. The first capacitor electrode and second capacitor electrode serve dual purposes: forming the storage capacitor and providing touch sensing functionality. This merging eliminates the need for separate touch sensing elements and their associated processing steps, thereby reducing process complexity while maintaining aperture ratio.
Solution Approach 2:
The capacitor electrodes are designed to perform multiple functions: storing electrical charge and detecting touch input. The first capacitor electrode and second capacitor electrode can function as both the storage capacitor components and the touch sensing elements, allowing one structure to serve multiple purposes without requiring additional dedicated components.
3Adaptability or versatility
If a touch sensing element is designed inside an OLED, then touch control function is provided, but the aperture ratio becomes smaller
Solution Approach 1:
The touch sensing function is merged with the capacitor structure by using the capacitor electrodes as sensing electrodes. The first capacitor electrode and second capacitor electrode form both the storage capacitor and the touch sensing element, eliminating the need for separate touch sensing components that would occupy display area and reduce aperture ratio.
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 design increases the storage capacitor area, enhances the aperture ratio, and simplifies the manufacturing process, improving the display's resolution and brightness while maintaining the light emitting area integrity.
Implementation Method 1
an electroluminescent layer, located on the pixel electrode of the first substrate
Implementation Method 2
the capacitor dielectric layer covers the upper capacitor electrode of the second substrate, where the conductive bump, the capacitor dielectric layer, and the upper capacitor electrode form a storage capacitor
Data Source
AI summary
A display panel includes a first substrate, an upper capacitor electrode, a capacitor dielectric layer, a second substrate opposite to the first substrate, a conductive bump, an electroluminescent layer, and a counter electrode. The upper capacitor electrode is disposed on an inner surface of the second substrate. The upper capacitor electrode is disposed on an inner surface of the second substrate. The capacitor dielectric layer covers the upper capacitor electrode of the second substrate. The first substrate has at least one pixel electrode and a first capacitor electrode separated from the pixel electrode. The conductive bump is protrusively disposed on the first capacitor electrode of the first substrate. The electroluminescent layer is sandwiched between the pixel electrode and the counter electrode.