Touch Pad Load Threshold Differentiation for Slim Design
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing touch pads in electronic devices, such as laptops, often experience erroneous detection of clicking operations due to the proximity of center and left/right buttons, leading to incorrect button registration and interference with slimming designs.
Innovation Solution
A touch pad configuration with distinct load sensors and a controller to differentiate between button regions, using different upper-limit values for load detection to accurately determine button depression states, and incorporating index protrusions for boundary sensing, ensuring precise button registration.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Length of moving object
If a capacitance sensor type click button region is used instead of physical click buttons to achieve slimming, then the device thickness is reduced, but erroneous detection of clicking operations occurs when the finger tip is floating or when button regions are close to each other
Solution Approach 1:
The patent applies local quality by setting different load threshold values for different button regions. The center button region uses a second upper-limit value (higher threshold) while the left/right button regions use a first upper-limit value (lower threshold). This localized differentiation allows the system to maintain high detection accuracy for each button type while using a unified capacitance sensor structure, thereby achieving both slimming and reliable detection.
Solution Approach 2:
The patent changes the parameter of load detection threshold to resolve the contradiction. By adjusting the threshold parameter differently for center and side button regions, the system can distinguish between intentional clicks and floating finger contacts. The controller compares the detected load value against region-specific thresholds, enabling accurate button registration while maintaining the slim capacitance sensor design.
2Area of stationary object
If the center button region and left/right button regions are disposed close to each other to save space, then the touch pad area is reduced, but erroneous detection occurs when both regions are contacted simultaneously
Solution Approach 1:
The patent applies local quality by assigning different load threshold characteristics to different button regions. The center button region has a higher second upper-limit value while left/right regions have a lower first upper-limit value. When multiple regions are contacted simultaneously, the controller uses these differentiated thresholds to determine which button region the operator intends to click, thereby maintaining measurement precision despite compact spatial arrangement.
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 effectively suppresses erroneous detection of clicking operations, enabling accurate button registration and maintaining a slim design by using distinct load thresholds and index features to differentiate button regions, enhancing user interaction and device usability.
Implementation Method 1
a load sensor configured to detect load at least at the center button region, the first button region and the second button region
Data Source
AI summary
A touch pad includes: a center button region; a first button region disposed adjacent to the center button region; a second button region disposed adjacent to the center button region on the opposite side of the first button region; a load sensor configured to detect load at least at the center button region, the first button region and the second button region; and a controller configured to determine a detection by the load sensor of load of a first upper-limit value or higher at least at one of the first and second button regions as a depressed state, and determine a detection by the load sensor of load of a second upper-limit value or higher at the center button region as a depressed state. The second upper-limit value and the first upper-limit value are different. Particularly, the second upper-limit value is larger than the first upper-limit value.