Sensitive Keyboard Layout for High-Resolution Touch Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional keyboards with sensitive key elements exhibit high mechanical complexity due to the need for a large number of sensor elements to accurately represent geometrical points on a surface, leading to increased mechanical and electrical complexity.
Innovation Solution
The keyboard subdivides the contact surface of key elements into zones with varying distances from adjacent elements, allowing each zone to produce distinct analogue electric signals, enabling identification of multiple points with fewer key elements through capacitive coupling and signal analysis, thereby reducing mechanical complexity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a large number of sensor elements are used to accurately represent geometrical points on the keyboard surface, then the measurement precision is improved, but the device complexity increases
Solution Approach 1:
The contact surface of each key element is segmented into multiple zones (e.g., four zones in a 2x2 matrix). By detecting which zone receives the finger touch, the system can identify multiple positions on a single key element without requiring multiple separate sensor elements. This segmentation allows one key element to function as multiple sensing points, reducing the total number of key elements needed.
Solution Approach 2:
Adjacent key elements are electrically coupled together to form a combined sensing unit. When a finger touches any zone within a group of coupled key elements, the system can determine the specific zone by analyzing the signal distribution across the coupled elements. This merging allows the system to detect multiple positions using fewer physical sensor elements than would traditionally be required.
2Quantity of substance
If the contact surface is subdivided into zones with different distances from adjacent key elements, then the number of identifiable points increases, but the manufacturing precision requirements increase
Solution Approach 1:
The system uses feedback from the electrical signals generated when a finger touches different zones to identify the touch position. By analyzing the relative signal strengths from adjacent key elements, the system can determine which zone was touched without requiring extremely precise mechanical boundaries. The electrical feedback compensates for variations in physical zone definitions.
Solution Approach 2:
The invention changes the parameter used for zone identification from purely mechanical boundaries to electrical signal characteristics. Instead of relying on precise physical demarcation lines between zones, the system identifies zones by analyzing the electrical parameters (signal strength, capacitance) from adjacent key elements, which are less sensitive to manufacturing tolerances.
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 increases the number of identifiable points on the keyboard surface beyond the number of key elements, enhancing resolution and reducing mechanical parts, allowing precise detection of finger position in a two-dimensional plane with a matrix arrangement.
Implementation Method 1
The key elements may be provided as capacitive key elements. The capacity of each key element may depend on the touch intensity and/or the proximity of the finger. Further, said pressure sensitive key elements are coupled by capacitive coupling effects.
Implementation Method 2
The sensor element may be sensitive to touch or proximity. The key elements may be provided as touch sensitive key elements and/or as proximity switches.
Data Source
AI summary
The present invention relates to a keyboard with a plurality of sensitive key elements (10, 12, 14) arranged on said keyboard according to a predetermined scheme. Each of the key elements (10, 12, 14) provides an analogue electric signal (U1, U2, U3). The analogous electric signal (U1, U2, U3) depends on the position of a fingertip. A contact surface of the key element (12) is subdivided into zones (A, B, C, D). The zones (A, B, C, D) are defined in such a way, that the zones (A, B, C, D) have different distances from the adjacent key elements (10, 14). Each zone (A, B, C, D) corresponds with a range of relationships between the signal (U2) of the key element (12) and the signal (U1, U3) of at least one adjacent key element (10, 14).