OLED display panel and electronic device
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional active-matrix organic light-emitting diode (AMOLED) on-cell display panels experience a low report rate for touch control due to high parasitic capacitance between touch electrodes and the cathode, caused by the short distance and structure of support pillars, which affects touch sensitivity and performance.
Innovation Solution
The OLED display panel features a support pillar design with a non-smooth transition to the pixel definition layer, where the common electrode layer forms a floating electrode over the support pillar and a continuous electrode over the pixel definition and light-emitting material layer, reducing parasitic capacitance by disconnecting the floating electrode from the common electrode.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If the touch electrode is placed directly on the upper surface of the thin film encapsulation layer, then the touch screen can be realized, but the parasitic capacitance between the touch electrode and the cathode is high due to the short distance, causing long RC delay and low scan frequency
Solution Approach 1:
The support pillar introduces a vertical dimension (Z-axis) to increase the distance between the touch electrode and cathode. By forming the support pillar extending from the pixel definition layer to between the touch electrode and cathode, the patent creates a three-dimensional structure that increases the vertical spacing, thereby reducing parasitic capacitance and RC delay while maintaining the on-cell touch screen configuration.
2Strength
If multiple support pillars with continuous cathode structure are formed on the pixel definition layer, then the pressure resistance and uniformity of cell thickness are enhanced, but the parasitic capacitance between the touch electrode and the cathode above the support pillar is higher, increasing RC delay
Solution Approach 1:
The patent applies local quality by creating a non-uniform cathode structure where the cathode is selectively interrupted above the support pillar. The cathode layer is discontinuous in the region above the support pillar, forming an isolated cathode segment, while remaining continuous in other regions. This localized modification reduces parasitic capacitance specifically above the support pillar without compromising the overall structural integrity and pressure resistance provided by the support pillars.
Data Source
AI summary
The present application provides an organic light-emitting diode (OLED) display panel and an electronic device. A projection of a touch electrode of the OLED display panel projected on a base substrate is at least partially overlapped with a projection of a support pillar projected on the base substrate. The support pillar includes at least one side surface. An angle between an upper top surface of the support pillar is less than or equal to 90 degrees, and/or an angle between the side surface and a lower bottom surface of the support pillar is greater than or equal to 90 degrees. A common electrode layer is disconnected at the support pillar. Accordingly, the present application improves a report rate for touch control and enhances touch sensitivity of the OLED display panel.