Protruding Touch Key Detection on Capacitive Display Panels
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing input display devices with capacitive touch panels struggle to accurately determine the presence or absence of touch operations on keyboard-shaped/protruding switches due to the limited change in electrostatic capacitance when a finger touches the protruding switch.
Innovation Solution
The input display device incorporates a capacitive touch panel with a cover glass having a keyboard-shaped/protruding switch, and utilizes a sensing unit to detect the position of an operation target approaching the panel. A determination unit then assesses the variation in sensed positions to accurately determine whether a touch operation is performed on the switch.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a keyboard-shaped/protruding switch is provided on the touch panel, then the tactile recognition of touch position is improved, but the accuracy of determining touch operation presence or absence deteriorates due to limited electrostatic capacitance change
Solution Approach 1:
The patent changes the detection parameter from electrostatic capacitance change to position variation. By detecting the position of the operation target (finger) as it approaches and touches the protruding switch, and calculating the variation in these positions, the system can reliably determine touch operations even when electrostatic capacitance change is limited due to the protruding structure.
2Reliability
If a thick cover glass is used for three-dimensional UI, then touch mistakes are reduced, but the electrostatic capacitance change during touch operation is limited
Solution Approach 1:
The patent transitions from detecting electrostatic capacitance (which is insensitive with thick cover glass) to detecting position variation of the operation target. This parameter change allows the system to maintain high detection sensitivity even when using thick cover glass for three-dimensional UI, as position detection is not affected by the cover glass thickness in the same way electrostatic capacitance detection is.
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 improves the accuracy of touch operation detection on keyboard-shaped/protruding switches by utilizing the variation in sensed positions, thereby minimizing erroneous determinations and enhancing user interaction with in-vehicle displays.
Implementation Method 1
a capacitive sensor, and a display. A transparent cover lens 26 having an uneven shape is attached on a touch panel 24 including a capacitive sensor
Implementation Method 2
A highly sensitive electrostatic sensor capable of detecting the electrostatic capacitance (distance) of the finger even when the finger is away from the sensor is used for the touch detection
Data Source
AI summary
An input display device includes a display configured to display an image, a capacitive touch panel attached on the display, a keyboard-shaped/protruding switch attached on the touch panel, a touch sensing unit configured to sense a position of an operation target when the operation target approaches the touch panel, and an operation determination unit configured to determine presence or absence of a touch operation on the keyboard-shaped/protruding switch based on a variation in positions of the operation target sensed by the touch sensing unit.