Touch Display Electrode Architecture for Pressure Sensing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Mutually-capacitive touch screens cannot detect external pressure or its location, lacking the capability to sense pressure magnitude without additional modules.
Innovation Solution
Incorporating a touch electrode array on an array substrate and a touch sensing electrode array on a color film substrate, where touch electrodes provide common, touch scanning, and pressure scanning signals, and receive pressure sensing signals, allowing for pressure detection without additional modules by utilizing the existing electrode architecture.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a mutually-capacitive touch screen structure is used, then touch sensing functionality is achieved, but pressure detection capability is lost
Solution Approach 1:
The touch electrodes are configured to perform multiple functions: providing common voltage signals during displaying periods, providing touch scanning signals during touch scanning periods, and providing pressure scanning signals/receiving pressure sensing signals during pressure detecting periods. This multi-functional design eliminates the need for separate pressure detection modules while maintaining pressure detection capability.
Solution Approach 2:
The electrode configuration and signal transmission mode are dynamically switched between different operating periods (displaying, touch scanning, pressure detecting). The touch electrodes can be configured in different states at different times to serve different functions, enabling the system to adaptively change its behavior based on the current operational phase.
2Device complexity
If existing electrode architecture is used for pressure detection, then device complexity is reduced, but signal interference between touch and pressure sensing may occur
Solution Approach 1:
The touch display device operates in periodic cycles with distinct phases: displaying periods, touch scanning periods, and pressure detecting periods. During each pressure detecting period, the touch electrodes provide pressure scanning signals and receive pressure sensing signals, while during touch scanning periods, they perform touch sensing. This periodic separation ensures that touch and pressure sensing operations do not interfere with each other, maintaining signal detection accuracy while using the same electrode architecture.
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
Enables the detection of pressure applied position and magnitude on touch screens, enhancing functionality without requiring additional hardware, by leveraging the existing electrode structure to form capacitors that change capacitance with applied pressure.
Implementation Method 1
by leveraging the existing electrode structure to form capacitors that change capacitance with applied pressure
Data Source
AI summary
The present disclosure provides a touch display device and a method for driving the touch display device. The touch display device includes an array substrate and a color film substrate arranged opposite to the array substrate; a touch electrode array disposed on the array substrate, and a plurality of touch sensing electrodes arranged along a first direction and disposed on the color film substrate. The touch electrode array includes M×N touch electrodes. The touch electrodes are insulated from each other. The touch sensing electrodes extend along a second direction perpendicular to the first direction, and the touch sensing electrodes are insulated from each other. An orthographic projection of each of the touch electrodes to a plane where the touch sensing electrodes are located at least partially overlaps with one of the touch sensing electrodes.