In-Cell Touch Panel Sub-Electrode Segmentation for Power Reduction

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Self-capacitance touch panels face challenges in reducing power consumption due to overlapping capacitance between electrodes and lines, limiting their development to larger sizes.

Innovation Solution

The configuration of self-capacitance electrodes on an in-cell touch panel, where each electrode comprises sub-electrodes with connecting lines that do not overlap with gate or data lines, minimizing overlapping capacitance and reducing the load on the electrodes, thereby decreasing power consumption.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If self-capacitance electrodes are made larger to improve touch sensing accuracy, then touch sensing accuracy is improved, but overlapping capacitance with gate and data lines increases, leading to increased power consumption

Engineering Contradiction:
Improvetouch sensing accuracyVSAvoidpower consumption
Core Design Contradiction:
Measurement precisionVSUse of energy by moving object

Solution Approach 1:

The self-capacitance electrode is divided into multiple sub-electrodes (first self-capacitance sub-electrode, second self-capacitance sub-electrode, etc.) arranged in a matrix pattern. This segmentation allows the electrode to maintain sufficient sensing area while reducing the overlapping area with gate and data lines, thereby reducing overlapping capacitance and power consumption while preserving touch sensing accuracy.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent introduces a matrix arrangement of sub-electrodes with connecting lines that extend in different directions (row direction and column direction). This dimensional arrangement optimizes the spatial distribution of electrode areas, allowing the electrode to cover sufficient display area for accurate touch detection while minimizing overlap with scanning lines through strategic positioning of connecting lines.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

2Area of stationary object

If self-capacitance electrode size is increased to cover more display area, then aperture ratio is improved, but overlapping capacitance with scanning lines increases, increasing power consumption

Engineering Contradiction:
Improveaperture ratioVSAvoidpower consumption
Core Design Contradiction:
Area of stationary objectVSUse of energy by stationary object

Solution Approach 1:

The electrode is segmented into multiple sub-electrodes with connecting lines extending in row and column directions. This segmentation enables the electrode to achieve larger effective aperture ratio while the connecting lines are strategically positioned to minimize overlap with gate and data lines, thus reducing power consumption despite increased electrode area.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

By arranging sub-electrodes in a matrix with connecting lines extending in different dimensions (row and column directions), the patent optimizes the spatial utilization. This allows the electrode to cover more display area for improved aperture ratio while the multi-dimensional arrangement of connecting lines reduces overlapping capacitance with scanning lines.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

3Reliability

If more conductive lines are added to connect self-capacitance electrodes to touch detecting chip, then electrical connection reliability is improved, but device complexity increases

Engineering Contradiction:
Improveelectrical connection reliabilityVSAvoiddevice complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent merges the function of connecting lines with the gate and data line layers by having the connecting lines extend in the row and column directions that align with the existing scanning line structure. This merging approach ensures reliable electrical connection from multiple sub-electrodes to the touch detecting chip while utilizing the existing line structure, thereby reducing device complexity.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The connecting lines serve multiple functions: they electrically connect adjacent sub-electrodes in series, they are positioned to minimize overlapping capacitance with scanning lines, and they utilize the existing row and column structure of the display panel. This multi-functionality reduces the need for additional dedicated connection structures, thereby reducing device complexity while maintaining connection reliability.

Inventive Principle:
Principle #6Universality (Multi-functionality)

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 configuration significantly reduces the power consumption of the in-cell touch panel, making it suitable for larger sizes and expanding its application scope while maintaining a wide aperture ratio.

Implementation Method 1

If the panel is not touched by a human body, the capacitance of each self-capacitance electrode is at a fixed value. If the panel is touched by a human body, the capacitance of the corresponding self-capacitance electrode is at a value of the fixed value plus the capacitance of the human body

Methodology Applied
Scientific EffectCapacitance: Capacitance

Implementation Method 2

There is an overlapping area between the self-capacitance electrode 101 and the gate lines 105 and also between the self-capacitance electrode 101 and the data lines 106. Thus, there is overlapping capacitance between the self-capacitance electrode 101 and the gate lines 105 as well as between the self-capacitance electrode 101 and the data lines 106

Methodology Applied
Scientific EffectOverlapping capacitance: Parasitic Capacitance

Data Source

PatentEP3316099B1Embedded touch screen and display device
Publication Date: 2021.06.23 BOE TECHNOLOGY GROUP CO LTD
  • EP3316099B1 patent drawingFigure 1
  • EP3316099B1 patent drawingFigure 2
  • EP3316099B1 patent drawingFigure 3~4a

AI summary

An in-cell touch panel and a display device are disclosed, in the in-cell touch panel, each of the self-capacitance electrodes (3) includes a plurality of self-capacitance sub-electrodes (31) which are insulated from each other and connecting lines (321, 322) for connecting the self-capacitance sub-electrodes; an orthographic projection on the first substrate (100) of each self-capacitance sub-electrode (31) does not overlap with an orthographic projection on the first substrate (100) of each gate line (1); and/or an orthographic projection on the first substrate (100) of each self-capacitance sub-electrode (31) does not overlap with an orthographic projection on the first substrate (100) of each data line (2). Thus, there is almost no overlapping area between the self-capacitance electrodes and the gate lines and/or there is almost no overlapping area between the self-capacitance electrodes and the data lines, thus there is almost no overlapping capacitance, and therefore the load of the self-capacitance electrode can be obviously reduced, and the power consumption of the in-cell touch panel can be reduced, which is especially appropriate for the in-cell touch panel of large size.