Array Substrate Touch Driving Signal Inversion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In display panels with integrated touch and display functions, parasitic capacitance between touch electrodes and scan lines/data lines leads to abnormal picture display due to coupling effects, causing a heavy load on touch electrodes.
Innovation Solution
The implementation of a method and structure where the control unit outputs touch driving signals with inverse polarities to adjacent groups of touch electrodes, and clock control switch units switch scan lines into a floating state, balancing the coupling effect and reducing parasitic capacitance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If touch electrodes and scan lines are integrated in the display panel, then the display panel can provide both display and touch functions, but parasitic capacitance between touch electrodes and scan lines causes coupling effects leading to abnormal picture display
Solution Approach 1:
The scan lines are divided into multiple segments corresponding to different groups of touch electrodes. During touch detection, only specific scan line segments are activated at different time periods, while other segments are disconnected. This segmentation isolates the parasitic capacitance effects to specific regions and time periods, preventing cumulative coupling effects that would cause abnormal picture display.
Solution Approach 2:
The patent implements periodic switching between display mode and touch detection mode. During touch detection, scan lines are periodically connected and disconnected based on the detection phase. This periodic action allows the system to alternate between normal display operation and touch detection, ensuring that parasitic capacitance effects are minimized during display phases while enabling touch functionality during detection phases.
2Adaptability or versatility
If multiple touch electrodes are arranged in the display region, then touch detection capability is enhanced, but parasitic capacitance between touch electrodes and data lines increases causing heavy load on touch electrodes
Solution Approach 1:
Touch electrodes are divided into multiple groups, and data lines are segmented to connect to specific groups at specific time periods. During touch detection, only certain data line segments are activated to connect to specific touch electrode groups, while other data line segments remain disconnected. This reduces the total parasitic capacitance load on any single touch electrode at any given time, while still enabling comprehensive touch detection across all electrodes through sequential scanning.
Solution Approach 2:
The patent implements dynamic connection and disconnection of data lines to touch electrode groups based on detection requirements. Instead of all data lines being continuously connected to all touch electrodes, the system dynamically activates only the necessary data line segments during specific detection phases. This dynamic approach reduces parasitic capacitance load while maintaining full touch detection capability.
3Productivity
If scan lines are continuously connected to the driving circuit, then display scanning operation is maintained, but during touch phase the coupling effect pulls electric potentials causing leak current through pixel units
Solution Approach 1:
The patent implements periodic switching of scan line connections during touch detection phases. At specific time periods corresponding to touch detection, scan lines are disconnected from the driving circuit to prevent coupling effects from pulling electric potentials. During display phases, scan lines are reconnected to restore normal scanning operation. This periodic disconnection and reconnection eliminates leak currents through pixel units while maintaining display functionality.
Solution Approach 2:
Before touch detection begins, the system preliminarily disconnects the scan lines from the driving circuit to prevent potential coupling effects. This preliminary action ensures that when touch detection starts, the scan lines are already isolated and cannot cause leak currents through pixel units. After touch detection completes, the scan lines are reconnected to resume display scanning.
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 allows for normal display operation while balancing the coupling effect on scan lines, improving touch performance by reducing the load on touch electrodes and eliminating parasitic capacitance issues.
Implementation Method 1
the overlapping structures and the high-integration of the display panel may cause a parasitic capacitance between the touch electrodes and the scan lines, between the touch electrodes and the data lines
Implementation Method 2
due to the coupling effect between the touch electrodes and the scan lines, the electric potentials of the scan lines would be pulled to be the same as the electric potentials of the touch electrodes
Data Source
AI summary
An array substrate, a display panel, a display device and a driving method for an array substrate are disclosed. The array substrate includes a display region and a non-display region. The display region is provided with a plurality of data lines and a plurality of scan lines. The plurality of scan lines intersect with the plurality of data lines to define a plurality of pixel units arranged in an array, and each of the plurality of scan lines is electrically connected with a row of the pixel units. The display region is further provided with N groups of touch electrodes arranged in an array, where N is a positive integer larger than or equal to 2. The non-display region is provided with a driving circuit, and a control unit, and in a touch phase, touch driving signals with inverse polarities are outputted by the control unit to two adjacent groups of the touch electrodes.