Non-linear Touch Sensor Electrode Patterns for Single-Edge Routing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional touch sensor designs face challenges in connectability, particularly when space constraints limit the ability to establish connections to more than one side or edge of the sensing surface, necessitating alternative electrode patterns that allow connections along a single edge while maintaining accurate touch position detection.
Innovation Solution
The implementation of non-linear electrode patterns that intersect within the sensing surface, allowing connections along a common edge, with a processor transforming reported positions from a conventional controller into physical coordinates using a lookup table or mathematical functions to account for the distortion in the electrode layout.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If conventional linear electrode patterns are used, then touch position detection accuracy is maintained, but connection routing requires additional space beyond a single edge
Solution Approach 1:
The patent applies curvature by transforming straight linear electrode patterns into curved or arcuate electrode patterns. This allows the electrodes to converge and meet at a common edge, enabling all connections to be routed from a single edge of the sensing surface without requiring additional space on multiple edges, thus resolving the contradiction between connectability and space requirements.
2Area of stationary object
If electrode patterns are distorted to meet at a common edge, then connection space is reduced, but touch position coordinates require transformation
Solution Approach 1:
The patent introduces a coordinate transformation system as an intermediary between the curved electrode pattern and the touch controller. This intermediary layer includes a lookup table or transformation algorithm that converts the distorted coordinates from the curved electrode pattern into standard linear coordinates that the controller can process, thereby managing the added complexity while achieving compact connection routing.
3Adaptability or versatility
If non-linear electrode patterns are implemented, then single-edge connectability is achieved, but manufacturing precision requirements increase
Solution Approach 1:
The patent applies preliminary action by pre-calculating and storing the coordinate transformations in a lookup table during the design phase. This pre-computed transformation data compensates for the inherent imprecisions in manufacturing curved electrode patterns, allowing the system to achieve accurate touch position detection even when the physical electrode positions have minor manufacturing variations.
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 enables flexible connectability along a single edge of the sensing surface without requiring additional space for routing connections, while maintaining high sensing resolution and accuracy in touch position determination.
Implementation Method 1
a controller chip connected to the electrodes and operable to measure changes in the electrical capacitance of each of the electrodes or the mutual-capacitance between combinations of the electrodes
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A touch-sensitive position sensor is disclosed. The sensor comprises an array of first electrodes and an array of second electrodes arranged in a pattern to provide a sensing surface, wherein at least some of the first electrodes and the second electrodes are arranged to follow paths which are non-linear within the sensing surface such that there are ends of the first electrodes and ends of the second electrodes which meet a common edge of the sensing surface. A controller is coupled to respective ones of the first electrodes and the second electrodes and arranged to determine a reported position for an object adjacent the sensing surface by measuring changes in an electrical parameter e.g. capacitance or resistance, associated with the first electrodes and the second electrodes which is caused by the presence of the object. The controller is further operable to provide an indication of the reported position in a first coordinate system defined relative to the first electrodes and the second electrodes, the sensor further comprises a processor arranged to receive the indication of reported position from the controller in the first coordinate system and to transform the reported position to an output position in a second coordinate system, wherein the transform is based on the non-linear pattern of electrodes. Thus, a sensor having electrodes which are distorted so as to meet a common edge may be provided for ease of connectability, with the distortion been accounted for through the transform performed by the processor.