Cross-Shaped Sensor Elements for In-Cell Touch Precision
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In-cell touch panels with square or diamond-shaped sensor elements experience degraded touch performance when a small contact area is used, as the contact region often falls within a single sensor element, leading to incorrect touch coordinate calculations and reduced precision.
Innovation Solution
The touch sensor employs cross-shaped or similarly configured sensor elements with a maximum inscribed circle diameter smaller than a square's, allowing for a higher probability of the contact region spanning multiple elements, thereby improving touch coordinate accuracy and precision.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If square-shaped or diamond-shaped sensor elements are used in in-cell touch panels, then the touch panel structure is simple and easy to manufacture, but the touch coordinate precision degrades when a small contact area is used
Solution Approach 1:
The patent applies asymmetry by changing the sensor element shape from symmetric square/diamond forms to asymmetric cross-shaped configurations. This asymmetric design creates overlapping detection regions between adjacent sensor elements, ensuring that even small contact areas interact with multiple elements. The cross shape extends detection capability in multiple directions (up, down, left, right) with unequal weighting, allowing precise coordinate calculation through weighted averaging of signals from multiple elements, thereby resolving the precision degradation issue while maintaining manufacturing simplicity.
2Area of stationary object
If the contact region falls within one sensor element, then the sensor element coverage is sufficient, but the touch coordinate calculation becomes inaccurate
Solution Approach 1:
The patent applies segmentation by dividing the touch detection function across multiple sensor elements through the cross-shaped configuration. Each arm of the cross extends into adjacent sensor element territories, effectively segmenting the detection responsibility. When a contact occurs, the signal is naturally distributed across multiple segmented elements rather than concentrated in one, enabling accurate coordinate calculation through proportional weighting of each element's contribution based on its signal strength relative to others.
3Measurement precision
If the contact region extends over multiple sensor elements, then the touch coordinate can be calculated more accurately, but the sensor element area must be reduced
Solution Approach 1:
The patent applies dimensionality change by extending the sensor element detection capability beyond its physical geometric boundaries through the cross-shaped design. The cross arms reach into adjacent element territories, creating a virtual extended detection area in multiple dimensions. This allows a single sensor element to effectively cover and detect contacts that would otherwise fall entirely within another element's area, enabling multi-element contact detection without reducing the physical area of individual elements.
Data Source
AI summary
Discussed is a touch sensor for use in an in-cell type touch sensor panel that includes a plurality of sensor elements, wherein each sensor element has a shape such that a maximum diameter of a circle able to be inscribed in the sensor element is smaller than a diameter of a circle inscribed in a square having the same area as the sensor element.