Capacitive Electrode Voltage Profiling for Temperature-Stable Touch Sensing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Capacitive sensor devices struggle with accurate detection of input objects in varying temperature environments due to temperature sensitivity, leading to ghost touches when objects heat up or cool down, especially in extreme conditions.
Innovation Solution
Implement a temperature stable profile sensing scheme by driving electrodes with a first and second voltage based on a temperature stable ratio, obtaining resulting signals, and performing object detection based on these signals.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional capacitive sensor devices operate with fixed voltage settings, then the device structure remains simple, but detection accuracy deteriorates in varying temperature environments causing ghost touches
Solution Approach 1:
The patent implements dynamic voltage adjustment by switching between first and second voltage settings based on detected temperature conditions. The processing system dynamically selects which subset of electrodes to drive with which voltage level, transforming the static voltage configuration into a dynamic adaptive system that responds to environmental changes.
Solution Approach 2:
The patent changes the voltage parameter based on temperature conditions. By setting different voltage levels (first voltage vs. second voltage) for different temperature ranges, the system adapts its electrical parameters to maintain detection accuracy across varying thermal environments without requiring complete system redesign.
2Reliability
If capacitive sensors operate in cold environments, then energy consumption is reduced, but temperature sensitivity causes ghost touches when objects heat up the device
Solution Approach 1:
The patent applies preliminary anti-action by preemptively adjusting voltage settings based on predicted temperature conditions. When cold environment operation is detected, the system proactively switches to voltage settings optimized for cold conditions, preventing ghost touches before they occur rather than reacting after temperature changes affect sensing.
Solution Approach 2:
The system incorporates feedback mechanisms where the processing system continuously monitors detection results and temperature conditions, then adjusts voltage settings accordingly. This closed-loop feedback ensures that when temperature changes cause potential ghost touches, the system detects the anomaly and corrects the voltage setting to restore accurate detection.
3Measurement precision
If the capacitive sensor device uses temperature compensation, then detection accuracy improves in varying temperatures, but the control system becomes more complex
Solution Approach 1:
The patent segments the electrode array into different subsets that can be independently controlled with different voltage settings. Rather than complicating the control of a single electrode system, the invention divides the sensing array into manageable segments, each optimized for specific temperature conditions, thereby distributing the control complexity across multiple simpler independent channels.
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
Ensures accurate input object detection across various environmental temperatures, preventing ghost touches and maintaining reliable operation in hot and cold conditions.
Implementation Method 1
capacitive sensor devices may include a sensing region, often demarked by a surface (e.g., display screen), in which the capacitive sensor device determines the presence, location and/or motion of one or more input objects
Data Source
AI summary
A method for performing a temperature stable profile sensing scheme is provided. The method comprises: setting, by a processing system, a first voltage for driving a first subset of a plurality of electrodes based on a second voltage and a temperature stable ratio for the first voltage and the second voltage; driving, by the processing system, the first subset of the plurality of electrodes using the first voltage and a second subset of the plurality of electrodes using the second voltage; obtaining, by the processing system, resulting signals based on driving the first subset using the first voltage and the second subset using the second voltage; and performing object detection based on the obtained resulting signals.