Touch Panel Cover Signal Switching for Display Noise Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional liquid crystal display devices with touch panels or protection covers experience 'unintentional sound' due to electrostatic charges and voltage differences between the display panel and cover panels, which existing solutions fail to adequately address.
Innovation Solution
The solution involves inputting display-drive signals into both the display panel and the cover panel, and using a selector to switch between touch-panel drive signals and display-drive signals, ensuring the cover panel is electrically conductive and receiving the display-drive signals to minimize voltage differences and prevent oscillation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If touch panel drive signals are input into the touch panel, then touch functionality is maintained, but voltage differences between display panel and cover panel generate electric fields causing unintentional sound
Solution Approach 1:
The touch panel's electrically conductive transparent films are made to serve dual functions: receiving touch panel drive signals for touch detection and receiving display-drive signals to suppress voltage differences. This multi-functionality allows the same components to address both touch operation and unintentional sound elimination without adding separate systems.
Solution Approach 2:
A selector circuit dynamically switches between inputting touch panel drive signals and display-drive signals into the touch panel's electrically conductive transparent films. The selector adapts the signal type based on operational requirements, enabling the system to maintain touch functionality when needed while suppressing voltage differences during display operation.
2Object-generated harmful factors
If display-drive signals are input into the cover panel, then voltage differences and electric fields are eliminated suppressing unintentional sound, but the cover panel must be electrically conductive adding device complexity
Solution Approach 1:
The existing electrically conductive transparent films in the touch panel structure are made to serve dual functions: receiving touch panel drive signals for touch detection and receiving display-drive signals to suppress voltage differences. This multi-functionality allows the same components to address both touch operation and unintentional sound elimination without adding separate systems.
Solution Approach 2:
The patent combines the touch panel's electrically conductive transparent films with the display drive signal input function. By merging these functions into the same structural components, the system eliminates the need for separate conductive layers or additional complexity to achieve voltage difference suppression.
3Adaptability or versatility
If selector switches between signal types, then appropriate signals are input for different operations, but additional control components increase device complexity
Solution Approach 1:
The selector circuit dynamically switches between inputting touch panel drive signals and display-drive signals into the touch panel's electrically conductive transparent films. The selector adapts the signal type based on operational requirements, enabling the system to maintain touch functionality when needed while suppressing voltage differences during display operation.
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 suppresses the generation of 'unintentional sound' by eliminating the electric field between the display and cover panels, significantly reducing the noise level from 22 dB to 12 dB, making the display device more silent.
Implementation Method 1
the first substrate 121 of the touch panel 120 may make contact with the second substrate 112 of the liquid crystal display panel 110. As a result, when the first substrate 121 of the touch panel 120 leaves the second substrate 112 of the liquid crystal display panel 110, electric charges 'e' are accumulated on a surface of the second substrate 112 of the liquid crystal display panel 110 due to a phenomenon called 'peeling charge'
Implementation Method 2
a first electrically conductive transparent film 123 formed on a surface the first substrate 121 facing the second substrate 122, and a second electrically conductive transparent film 124 formed on a surface the second substrate 122 facing the first substrate 121
Data Source
AI summary
A display unit includes a display panel having a display screen on which images are displayed, and (b) a touch panel covering the display screen therewith and detecting a touch thereto made by a user. The touch panel detects the touch in accordance with touch-panel drive signals input thereto. The display panel displays images in accordance with display-drive signals input thereto. The touch panel is switched between a first condition in which the touch-panel drive signals are input into the touch panel and a second condition in which the touch panel is electrically open.