Overcoat Layer Dielectric Constant for Touch Sensitivity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Display devices with touch panels experience variations in touch sensitivity due to step differences caused by spacers, leading to inconsistent user input recognition across the display panel.
Innovation Solution
Incorporating overcoat layers with varying dielectric constants, where the dielectric constant is higher over spacers and lower in non-overlapping regions, to compensate for sensitivity variations and maintain uniform touch sensitivity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Shape
If a spacer is disposed on the bank layer to define pixel structure, then the pixel structure is properly formed, but the touch sensitivity varies in the region overlapping the spacer
Solution Approach 1:
The patent applies local quality by configuring the overcoat layer with different dielectric constants in different regions. Specifically, the region overlapping the spacer has a first dielectric constant while the non-overlapping region has a second dielectric constant. This local differentiation compensates for the capacitance change caused by the spacer, maintaining uniform touch sensitivity across the display panel while preserving the pixel structure definition function of the spacer.
Solution Approach 2:
The patent changes the dielectric constant parameter of the overcoat layer to resolve the touch sensitivity variation. By adjusting the dielectric constant in the region overlapping the spacer (first dielectric constant) compared to the non-overlapping region (second dielectric constant), the patent compensates for the capacitance change induced by the spacer, thereby maintaining consistent touch sensitivity across different portions of the display panel.
2Reliability
If the dielectric constant of the overcoat layer is increased in the region overlapping the spacer, then the touch sensitivity variation is compensated, but the device structure becomes more complex
Solution Approach 1:
The patent implements local quality by creating regions with different dielectric constants within the overcoat layer. The region overlapping the spacer is configured with a first dielectric constant to compensate for capacitance changes, while the non-overlapping region uses a second dielectric constant. This localized differentiation addresses the touch sensitivity issue without requiring complete structural redesign of the entire device.
Solution Approach 2:
The patent modifies the dielectric constant parameter of the overcoat layer in specific regions to compensate for touch sensitivity variations caused by the spacer. By changing the dielectric constant in the overlapping region while maintaining a different value in non-overlapping regions, the patent achieves uniform touch sensitivity with a relatively simple approach that doesn't require complex additional structures.
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 effectively reduces touch sensitivity variations caused by spacers, ensuring consistent user input recognition and improved performance across the display panel.
Implementation Method 1
A dielectric constant of the at least one overcoat layer in a region overlapping the spacer in a thickness direction of the substrate is larger than a dielectric constant of the overcoat layer in a region that does not overlap the spacer in the thickness direction of the substrate
Data Source
AI summary
A display device that includes a substrate and a bank layer disposed on the substrate. The bank layer defines an emission area and a non-emission area of a pixel. A spacer is disposed on a portion of the bank layer. A touch member is disposed above the spacer. At least one overcoat layer is disposed on the touch member. A dielectric constant of the at least one overcoat layer in a region overlapping the spacer in a thickness direction of the substrate is larger than a dielectric constant of the overcoat layer in a region that does not overlap the spacer in the thickness direction of the substrate.