Capacitance Sensing Noise Filtering via Difference Value Analysis
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Capacitance sensing systems in user interface devices, such as touchscreens, face accuracy and consistency issues due to noise signals, which affect the detection of a conductive object's presence and position, leading to less accurate input detection.
Innovation Solution
The system determines differences between presence values detected by the sensing system to identify and filter out error-affected values, using reference difference values to modify presence values and improve accuracy, allowing for more precise position calculation without requiring division or multiplication operations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If capacitance sensing is used to detect presence of conductive objects, then user interface functionality is enabled, but noise signals reduce detection accuracy and consistency
Solution Approach 1:
The patent extracts and removes erroneous presence values from the dataset by comparing difference values against expected patterns. By identifying and eliminating outliers caused by noise signals, the system isolates accurate presence data for reliable position calculation.
Solution Approach 2:
The system uses reference difference values derived from known good presence values to create a feedback mechanism. This reference pattern is compared against actual difference values to identify and correct erroneous measurements, continuously improving detection accuracy through self-validation.
2Measurement precision
If traditional position calculation methods are used, then position can be determined, but computational expense increases due to division and multiplication operations
Solution Approach 1:
The patent replaces complex mathematical operations (division and multiplication) with simpler arithmetic operations (addition and subtraction). By using difference values between adjacent presence values to directly calculate position, the system achieves the same measurement precision with significantly reduced computational expense.
3Ease of operation
If all presence values are used for position calculation, then calculation is simplified, but accuracy decreases due to error-affected values
Solution Approach 1:
The system performs preliminary filtering of presence values by calculating difference values and comparing them against reference patterns before position calculation. This pre-processing step identifies and removes erroneous values, ensuring that only accurate presence data is used in the final position calculation.
Solution Approach 2:
The patent introduces difference values as an intermediary between raw presence values and final position calculation. This intermediate step acts as a filter that highlights accurate measurements while suppressing erroneous ones, enabling both simplicity and precision in the overall 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 approach enhances the accuracy of presence detection and position calculation, reducing computational expense and noise interference, resulting in more reliable user input processing.
Implementation Method 1
Capacitive sensing typically involves measuring a change in capacitance associated with the capacitive sensor elements to determine a presence conductive object relative to the capacitive sensor elements
Data Source
AI summary
A method and apparatus determine a difference value, the determined difference value reflecting a difference between a plurality of presence values. In an embodiment, the method and apparatus perform an operation associated with the plurality of presence values, based on the determined difference value.