Capacitive Sensing Mechanism for Touch, Hover, and Force Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing touch and hover input sensing technologies in computing devices often increase cost and complexity by using multiple sensing mechanisms or separate sensors for different inputs, such as capacitive sensing for touch and infrared image sensors for hover, which can lead to increased device complexity and cost.
Innovation Solution
A touch-sensitive display device that utilizes a common capacitive sensing mechanism to detect touch, hover, and force inputs through an electrode matrix, a deformable layer, and a conductive plane, operating in either mutual or self-capacitance modes to consolidate these functions into a single stack, reducing complexity and cost.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If multiple sensing mechanisms (capacitive and infrared) are used to detect touch and hover input, then sensing capability is improved, but device complexity and cost increase
Solution Approach 1:
The capacitive sensing mechanism is designed to perform multiple functions: detecting touch input, hover input, and force applied. By making the capacitive sensing system universal, the patent eliminates the need for separate infrared sensors, thereby reducing device complexity while maintaining comprehensive sensing capability
Solution Approach 2:
The patent combines touch sensing, hover sensing, and force sensing into a single capacitive sensing system. The electrode matrix and controller are configured to differentiate between touch, hover, and force inputs through capacitive measurements, merging multiple sensing functions into one integrated mechanism
2Measurement precision
If separate sensors are provided for detecting touch and measuring force, then detection accuracy is improved, but device complexity and cost increase
Solution Approach 1:
The capacitive sensing mechanism is designed to simultaneously detect touch input, hover input, and force applied through different capacitive measurements. The controller differentiates between these inputs by analyzing capacitance changes at different thresholds, providing accurate detection of multiple input types with a single sensing system
Solution Approach 2:
The patent uses different capacitance threshold levels to differentiate between touch, hover, and force inputs. By changing the interpretation parameters (capacitance thresholds) rather than using separate sensors, the system achieves accurate detection of multiple input types while maintaining a single sensing mechanism
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
The solution enables efficient detection of touch, hover, and force inputs using a single capacitive sensing mechanism, reducing device complexity and cost while improving signal-to-noise ratio and enabling three-dimensional hand gesture recognition.
Implementation Method 1
A device configured to receive touch and hover input may sense touch input capacitively
Implementation Method 2
at least a portion of the electrode matrix is configured to resiliently deflect in response to a force applied
Data Source
Figure 1~2
Figure 3
Figure 4
AI summary
Embodiments of a touch-sensitive display device are disclosed herein. According to a first aspect, a touch-sensitive display device comprises an electrode matrix including transmit electrodes and receive electrodes; a conductive plane; and a controller configured to cause a transmit electrode driver to drive the transmit electrodes in a mutual capacitance mode. The controller is configured to cause the transmit electrodes, the receive electrodes, and the conductive plane to be connected to a common charging voltage during charge periods of a self-capacitance mode; to, during discharge periods of the self-capacitance mode that alternate with the charge periods, cause the transmit electrodes, the receive electrodes, and the conductive plane to be connected to a common reference voltage; and to, during the discharge periods, cause the transmit electrodes and the receive electrodes to be coupled to receive circuitry configured to measure self-capacitance of the transmit electrodes and the receive electrodes.