Footstep Electrode Touch Signal Circuit for LCD
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Capacitive-type touch control panels in LCDs face challenges in compact design due to the need for multiple bonding pads and pins, leading to increased weight and production costs, as well as thickness, which complicates the production process.
Innovation Solution
A touch signal transmission circuit with a first patterned electrode layer and a second patterned electrode layer, shaped like footsteps, reduces the number of electrodes and bonding pads by using interlaced first and second electrodes with non-overlapping contact points, allowing for more compact and lightweight designs.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If multiple straight electrodes are arranged closely in the first and second electrode layers to increase touch points, then touch position location precision is improved, but the number of bonding pads and pins increases, leading to increased device complexity and production difficulty
Solution Approach 1:
The patent transforms the traditional straight-line electrode arrangement into a stepped (multi-level) electrode structure. By adding vertical dimensionality through steps, the electrode can maintain multiple contact points along its length while reducing the horizontal density of electrodes required, thereby reducing the number of bonding pads needed.
Solution Approach 2:
The electrode is divided into multiple stepped segments along its length, with each step creating additional contact points. This segmentation allows the electrode to achieve multiple touch detection points without requiring proportionally more electrodes or bonding pads, as the stepped structure multiplies the effectiveness of each electrode segment.
2Reliability
If the touch control panel is designed as an individual structure with multiple electrodes and bonding pads, then touch detection function is achieved, but the overall thickness and weight of the display increase
Solution Approach 1:
The patent integrates the touch control panel structure with the display structure by mounting the stepped electrode layers directly onto the display substrate. This merging eliminates the need for a completely separate touch control panel assembly, reducing overall weight and thickness while maintaining touch detection functionality.
Solution Approach 2:
By using stepped electrodes that extend in multiple levels rather than simple planar arrangements, the patent achieves effective touch detection with fewer material layers and less overall structure, thereby reducing weight and thickness.
3Measurement precision
If more bonding pads and pins are used to support more touch points, then touch position location precision is improved, but production difficulty and costs increase
Solution Approach 1:
The stepped electrode structure creates multiple contact points along the vertical steps of each electrode rather than requiring multiple separate electrodes. This dimensional approach allows multiple touch detection points to be achieved with fewer bonding pads, simplifying the manufacturing process.
Solution Approach 2:
The patent changes the geometric parameters of the electrodes by introducing stepped structures with varying heights and positions. This parameter change allows the same electrode to provide multiple contact points, reducing the total number of electrodes and bonding pads required, thereby easing manufacturing.
Data Source
AI summary
A touch signal transmission circuit for a touch control LCD is mounted to an inner side of an upper substrate of the LCD, having a first patterned electrode layer and a second patterned electrode layer, which are electrically insulated from each other and partially overlap each other in intervals to define a touch control section. Each of the first and second patterned electrode layers includes a plurality of electrodes in the shape of footsteps. The electrodes are interlaced with one another, having some parts overlapping and right corresponding to each other to define a plurality of touch-sensitive points. In this way, only fewer footstep-shaped electrodes are needed to cover the whole touch control section to decrease the number of bonding pads and pins of a touch control IC. Besides, a lot of touch sensitive points are closely disposed in the touch control section to keep quick detection and decoding.