Piezo Display Tactile Panel Spacer Vibration Attenuation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing display devices cannot simultaneously achieve a low-frequency force feedback function and ultrasonic tactile function using a single piezoelectric actuator due to attenuation of low-frequency vibrations through the panel, preventing effective integration of both feedback mechanisms.
Innovation Solution
A display device configuration that includes a display panel, a touch panel, a spacer, a tactile panel, and a piezoelectric actuator, where the tactile panel is separated from the touch panel by a spacer, allowing the piezoelectric actuator to generate vibrations in both ultrasonic and low-frequency bands without attenuation, with specific thickness and material properties to enhance strength and functionality.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If the piezoelectric actuator is placed at the edge of the tactile panel to achieve ultrasonic tactile function, then the tactile sensation can be expressed, but the low-frequency vibration is attenuated in the middle of the panel and cannot function effectively
Solution Approach 1:
The patent divides the tactile panel into two functional zones: a first tactile panel for ultrasonic tactile sensation and a second tactile panel for low-frequency force feedback. This segmentation allows each panel to be optimized for its specific frequency range, with the first panel positioned at the edge for ultrasonic vibration and the second panel positioned to receive low-frequency vibration from the piezoelectric actuator placed directly beneath it.
Solution Approach 2:
The patent introduces a vibration transmission structure (including a vibration transmission member and supporting structure) as an intermediary between the piezoelectric actuator and the second tactile panel. This intermediary ensures efficient low-frequency vibration transmission from the actuator to the second panel, overcoming the attenuation problem that would occur if the actuator were placed at the edge.
2Reliability
If the piezoelectric actuator is placed directly under the back of the tactile panel to achieve low-frequency force feedback, then the force feedback function can be achieved, but the ultrasonic tactile function cannot be expressed
Solution Approach 1:
The patent segments the tactile feedback functionality into two separate panels: the first tactile panel for ultrasonic tactile sensation (positioned at the edge where the actuator can generate standing waves) and the second tactile panel for low-frequency force feedback (positioned to receive direct vibration from the actuator). This segmentation allows both functions to coexist without interference.
Solution Approach 2:
The piezoelectric actuator is designed with multi-functionality, capable of generating both ultrasonic vibrations (for tactile sensation) and low-frequency vibrations (for force feedback). The actuator serves multiple purposes by adjusting its operating frequency, while the dual-panel structure ensures both functions can be effectively demonstrated simultaneously.
3Strength
If glass of thickness 0.2 to 1.0 mm is used to ensure strength, then the display panel has sufficient strength, but the tactile sensation and vibration transmission are compromised
Solution Approach 1:
The patent segments the cover structure into a first cover glass (0.2-1.0mm thick) for structural strength and a second cover glass (0.05-0.3mm thick) for tactile sensation. The first cover glass provides the necessary mechanical strength, while the thinner second cover glass allows effective vibration transmission for tactile feedback without compromising overall structural integrity.
Solution Approach 2:
The patent applies local quality by using different glass thicknesses in different regions: the first cover glass uses standard thickness (0.2-1.0mm) for structural strength, while the second cover glass uses reduced thickness (0.05-0.3mm) in the tactile feedback area to enhance vibration transmission. This localized variation optimizes both strength and tactile performance.
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
Enables both force feedback and tactile functions with high strength, allowing for effective tactile sensation and low-frequency vibration transmission without compromising the display device's structural integrity.
Implementation Method 1
a piezoelectric actuator disposed on the third principal surface and generating vibration
Implementation Method 2
The abovementioned spacer may include a material having an elastic modulus of 1.0×10^6 to 6.0×10^6 Pa
Implementation Method 3
Vibration in the ultrasonic band forms standing waves on the tactile panel
Data Source
AI summary
[Object]To provide a display device and an electronic device each capable of implementing both a force feedback function and a tactile function and having high strength.[Solving Means]A display device according to the present invention includes a display panel, a touch panel, a spacer, a tactile panel, and a piezoelectric actuator. The touch panel is placed on the display panel and has a first principal surface on the display panel side and a second principal surface on the side opposite to the first principal surface. The tactile panel is placed on the spacer and has a third principal surface facing the second principal surface with a gap between the third and second principal surfaces and a fourth principal surface on the side opposite to the third principal surface. The piezoelectric actuator is placed on the third principal surface and causes vibration. When a first thickness is defined as the thickness from the second principal surface to the fourth principal surface and a second thickness is defined as the thickness from the second principal surface to the third principal surface, the first thickness is 0.5 to 1.5 mm, is equal to or larger than the thickness obtained by adding 0.3 mm to the second thickness, and is equal to or smaller than the thickness obtained by adding 1 mm to the second thickness.