Self-Capacitance Touch Panel with Reflection Electrode for Hovering Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing projected capacitive touch panels are unable to perform hovering touch operations, which are essential for advanced gesture recognition in mobile devices, due to limitations in current technologies such as optical photographic or infrared scanning modes that face issues with hand shadow, ambient light interference, and power consumption.
Innovation Solution
A self-capacitance input device with a sensing electrode layer, a reflection and deflection electrode layer, an insulation layer, and amplifiers with adjustable gain, along with a sensing control circuit and selection switch circuits, which enables the detection of hovering gestures by manipulating electric flux lines to enhance sensing range and accuracy.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If optical photographic or infrared scanning modes are used for hovering detection, then hovering gesture detection capability is achieved, but power consumption increases and reliability deteriorates due to hand shadow and ambient light interference
Solution Approach 1:
The patent replaces optical/infrared detection systems with an electrical field-based self-capacitance sensing system. The touch panel uses conductive layers that generate electrical fields to detect hovering objects through capacitance changes, eliminating the need for optical components and significantly reducing power consumption while avoiding interference from ambient light and hand shadows
Solution Approach 2:
The patent modifies the electrical field parameters by adjusting the strength and distribution of electrical fields generated by the conductive layers. By changing field strength parameters and using differential capacitance measurement techniques, the system can detect hovering objects at different distances while maintaining low power consumption and high reliability
2Adaptability or versatility
If optical photographic or infrared scanning modes are used for hovering detection, then hovering gesture detection capability is achieved, but reliability deteriorates due to hand shadow and ambient light interference
Solution Approach 1:
The patent replaces optical/infrared detection systems with an electrical field-based self-capacitance sensing system. The touch panel uses conductive layers that generate electrical fields to detect hovering objects through capacitance changes, eliminating the need for optical components and significantly reducing power consumption while avoiding interference from ambient light and hand shadows
Solution Approach 2:
The patent introduces an intermediary electrical field between the touch panel and the hovering object. The conductive layers generate electrical fields that interact with the hovering object's capacitance, serving as an intermediary mechanism that reliably detects the object's presence, position, and movement without being affected by optical interference
3Use of energy by stationary object
If conventional self-capacitance sensing is used, then power saving and compact design are achieved, but hovering touch detection capability is lost
Solution Approach 1:
The patent introduces dynamic control of electrical field strength and distribution in the self-capacitance sensing system. By dynamically adjusting the voltage applied to conductive layers and using multiple sensing states, the system can differentiate between hovering and contact states, enabling hovering detection while maintaining the power-efficient and compact characteristics of self-capacitance technology
Solution Approach 2:
The patent segments the sensing function into multiple conductive layers with different electrical characteristics. By using separate driving and sensing conductive layers, the system can independently control field generation and signal detection, enabling hovering detection capability while maintaining power efficiency and compact design
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
Enables effective hovering touch detection, improving the capability of projected capacitive touch panels to recognize gestures without the limitations of existing technologies, enhancing user interaction with mobile devices by providing a power-efficient and reliable solution.
Implementation Method 1
one conductor line is concurrently connected to the driving and sensing units 110, 120 in order to first drive the conductor line and then sense the change of a signal on the conductor line thereby determining the magnitude of self-capacitance
Implementation Method 2
sense the change of a signal on the conductor line thereby determining the magnitude of self-capacitance
Implementation Method 3
manipulating electric flux lines to enhance sensing range and accuracy
Implementation Method 4
at least one amplifier with a gain greater than zero having an output coupled to the reflection and deflection electrode layer
Data Source
AI summary
A self-capacitance input device with hovering touch includes a sensing electrode layer, a reflection and deflection electrode layer, an insulation layer, and an amplifier with a gain greater than zero. The sensing electrode layer has a plurality of sensing electrodes on one side for sensing a touch or approach of an external object. The reflection and deflection electrode layer is disposed on the other side of the sensing electrode layer and has at least one reflection and deflection electrode. The insulation layer is disposed between the sensing electrode layer and the reflection and deflection electrode layer. The amplifier has an output coupled to the reflection and deflection electrode layer.