Metal Pattern Shielding for Touch Sensor Interference
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In ultra-slim display devices, the integration of touch sensors within the display panel leads to interference issues due to their proximity to other components, affecting touch recognition accuracy and image quality, especially when multiple touch sensors are embedded together.
Innovation Solution
A display device design featuring a metal pattern with low sheet resistance formed on a conductive layer, which acts as a shielding layer to reduce interference between touch sensors and other components, allowing for precise touch recognition and improved image quality by creating an equipotential surface and minimizing noise in touch signals.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Length of moving object
If a touch sensor is embedded within a display panel to achieve ultra-slim design, then the device thickness is reduced, but interference between the touch sensor and other components increases, deteriorating touch recognition accuracy
Solution Approach 1:
A conductive layer is introduced as an intermediary component between the touch sensor and other display panel components. This conductive layer acts as a shield that blocks electromagnetic interference while allowing the touch sensor to function accurately within the ultra-slim structure.
Solution Approach 2:
The sheet resistance of the conductive layer is optimized to specific ranges (10-100 ohms/square) to achieve the right balance between shielding effectiveness and electrical performance, resolving the interference issue without compromising touch recognition accuracy.
2Adaptability or versatility
If multiple touch sensors are embedded together to provide various user interfaces, then functional versatility is improved, but interference between the touch sensors increases, deteriorating touch sensing accuracy
Solution Approach 1:
The conductive layer serves as a common shield for multiple touch sensors, isolating them from mutual interference while allowing them to operate simultaneously. This enables multiple touch sensor types to coexist without degrading each other's performance.
Solution Approach 2:
The conductive layer is configured to maintain equipotential conditions across the display panel, preventing potential differences that could cause interference between multiple touch sensors and ensuring accurate touch sensing for all sensors.
3Object-affected harmful factors
If the conductive layer is extended to cover the entire bottom surface of the lower substrate to improve shielding, then interference blocking is enhanced, but manufacturing complexity increases
Solution Approach 1:
Instead of requiring complete coverage, the conductive layer is extended to cover essential areas with optimized dimensions. This partial coverage approach provides sufficient shielding effectiveness while simplifying the manufacturing process and reducing material usage.
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
The solution effectively reduces interference between touch sensors and other display panel components, enhancing touch recognition accuracy and image quality by stabilizing the conductive layer and providing a low-resistance path for electrical signals, while also addressing external light reflection and static electricity discharge.
Implementation Method 1
a metal pattern having a width of several hundred nm and making an interface with a conductive layer is formed on a lower substrate whose one surface is covered with the conductive layer
Implementation Method 2
a ground voltage can be applied to a conductive layer through a metal pattern having a low sheet resistance in order to block interference in sensing a user's touch
Data Source
Figure 1
Figure 2A~2B
Figure 3
AI summary
Provided is a display device (100) that includes a display panel (110) defined with an active area (A/A) displaying an image and an inactive area (I/A) outside the active area (A/A), the display panel (110) including a substrate (230) having a first surface and a second surface opposite the first surface; a plurality of pixels on the first surface of the substrate (230) in the active area (A/A), each pixel including a pixel drive circuit; a transparent conductive layer (IM) on the second surface of the substrate (230) covering the active area (A/A) and a part of the inactive area (I/A); and a metal pattern (MP) on the second surface of the substrate (230) in the inactive area (I/A), the metal pattern (MP) electrically connected to the transparent conductive layer (IM), receiving an electrical signal and having a lower resistance than the transparent conductive layer (IM), wherein the metal pattern (MP) serves as a conductive path to reduce a potential difference with respect to the electrical signal in an entire area of the transparent conductive layer (IM) compared to a display device without the metal pattern (MP).