Capacitive Sensor Signal Synchronization for Hover Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing sensor devices for personal digital assistants and personal computers face challenges in accurately detecting input information without firmware correction, particularly when the input means, such as a finger, is close to the electrodes but not in direct contact, due to difficulties in sensing changes in electrostatic capacitance.
Innovation Solution
The sensor device incorporates a panel with a first electrode, a second electrode, and a third electrode, along with a control circuit that includes a timing control circuit and amplifiers, which generates synchronization signals with inverted or same polarity to amplify and provide to the electrodes, allowing for effective detection of input information even without firmware correction by shielding undesired electric fields.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a capacitive sensor detects input information by extracting changes in electrostatic capacitance, then the sensor can detect input from conductive objects, but the detection accuracy deteriorates when the input means is close to but not in direct contact with the electrodes
Solution Approach 1:
The patent introduces a third electrode as an intermediary element between the first electrode and the second electrode. This third electrode mediates the electrostatic coupling by providing an additional capacitive path, enabling the sensor to detect input information more accurately even when the input means is close to but not in direct contact with the electrodes. The third electrode acts as a mediator that enhances the electrostatic coupling strength without requiring direct contact.
2Device complexity
If the sensor operates without firmware correction, then the device complexity is reduced, but the detection precision for hover and gesture inputs deteriorates
Solution Approach 1:
The patent changes the electrical parameters of the sensor by introducing a third electrode with specific capacitive coupling relationships. By adjusting the capacitive values between the first, second, and third electrodes, the system achieves improved detection precision for hover and gesture inputs without requiring firmware correction. The parameter change in the sensor structure enables the hardware itself to provide the necessary correction that would otherwise require firmware intervention.
3Device complexity
If the sensor uses traditional two-electrode configuration, then the device structure is simple, but the ability to detect input coordinates and distance without firmware correction deteriorates
Solution Approach 1:
The patent segments the sensor into three distinct electrodes (first electrode, second electrode, and third electrode) with specific spatial arrangements and capacitive coupling relationships. This segmentation allows each electrode to serve a specific function: the first and second electrodes detect input coordinates while the third electrode enhances the detection of distance and hover states. The segmented structure enables independent optimization of different detection capabilities without requiring firmware correction.
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 configuration enables accurate detection of input information, including coordinates and distance, by amplifying synchronization signals and providing them to the electrodes, enhancing the sensor's ability to detect inputs without the need for firmware correction, thereby improving hover detection and gesture recognition.
Implementation Method 1
detect changes in electrostatic capacitance. Therefore, the display device can detect input information by the input means by extracting the change in electrostatic capacitance (strength of electrostatic capacitive coupling) generated at the above electrodes when the input means comes close to the electrodes
Implementation Method 2
the first amplifier amplifying the second synchronization signal and providing the amplified second synchronization signal to each of the floating ground line and the first electrode
Data Source
AI summary
According to one embodiment, a sensor device includes a panel and a control circuit. The panel includes an insulating layer, a first electrode, and a second electrode. The control circuit including a first circuit including a timing control circuit and a first amplifier, and a second circuit including a detection circuit connected to a ground line. During a first sensing drive period, the first output unit outputs a first synchronization signal, the timing control circuit outputs a second synchronization signal, the first amplifier provides the amplified second synchronization signal to each of the floating ground line and the first electrode, and the detector reads a change in a sensor signal.