Transcapacitance Force Sensing with Dedicated Receiver Electrodes
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current capacitive sensing technologies in integrated display devices lack effective force sensing capabilities, as they primarily focus on proximity and motion detection without accurately measuring the force applied by input objects.
Innovation Solution
The integration of a processing system with sensor electrodes and force receiver electrodes, where the sensor electrodes are configured to deflect towards the force receiver electrodes, allowing for the determination of force information through transcapacitive measurements, enabling the detection of force applied by input objects while maintaining capacitive sensing and display updating functions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If traditional capacitive sensing technologies are used in integrated display devices, then proximity and motion detection functions are maintained, but force sensing capabilities are lacking
Solution Approach 1:
The sensor electrodes serve multiple functions: they act as common electrodes for display updating, capacitive sensing electrodes for touch detection, and force receiver electrodes for force measurement. This multi-functionality allows the same electrode structure to enable proximity, motion, and force sensing without adding separate dedicated structures for each function.
Solution Approach 2:
The electrode system is segmented into sensor electrodes (disposed between input surface and force receiver electrode) and force receiver electrodes (disposed below the display cell). This segmentation allows independent optimization of each electrode's function while maintaining their collaborative role in force sensing through transcapacitance measurements.
2Measurement precision
If sensor electrodes are configured to deflect toward force receiver electrodes for force measurement, then force information can be determined, but the structural stability of the display device may be compromised
Solution Approach 1:
The sensor electrodes are implemented as flexible thin film structures that can deflect toward the force receiver electrodes when force is applied. This flexibility enables the electrodes to respond to applied force through deflection, which modulates the transcapacitance signal for force measurement while maintaining overall structural integrity.
Solution Approach 2:
The system uses transcapacitance measurements between sensor electrodes and force receiver electrodes to detect force-induced deflections. The processing system analyzes changes in capacitive coupling as feedback signals to determine force information, enabling precise force measurement through electrical feedback rather than direct mechanical measurement.
3Adaptability or versatility
If dedicated force receiver electrodes are added below the display cell, then force sensing is enabled, but manufacturing complexity increases
Solution Approach 1:
The force receiver electrodes are merged with the existing display electrode structure and disposed below the display cell in the same manufacturing plane. This integration allows force sensing functionality to be added without requiring separate manufacturing processes or additional layers that would complicate production.
Solution Approach 2:
The force receiver electrodes serve dual purposes: they act as receiver electrodes for transcapacitance-based force sensing and can potentially serve as common electrodes for display updating. This multi-functionality reduces the need for additional dedicated components and simplifies the overall manufacturing process.
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 solution enables accurate force sensing in integrated display devices, allowing for the determination of both position and force applied by input objects, enhancing the input device's functionality and user interaction capabilities.
Implementation Method 1
determine force information for an input object based on the resulting signals
Implementation Method 2
Sensing force using transcapacitance with dedicated force receiver electrodes
Data Source
AI summary
An example integrated display device and capacitive sensing device having an input surface includes a plurality of sensor electrodes, wherein each of the plurality of sensor electrodes comprises at least one common electrode configured for display updating and capacitive sensing. The device further includes at least one force receiver electrode, wherein the plurality of sensor electrodes are disposed between the input surface and the at least one force receiver electrode and wherein at least a portion of the plurality of sensor electrodes are configured to deflect toward the at least one force receiver electrode. The device further includes a processing system, coupled to the plurality of sensor electrodes, configured to drive at least a portion of the plurality of sensor electrodes with force sensing signals while receiving resulting signals from the at least one force receiver electrode, and determine force information for an input object based on the resulting signals.