Vibration Device Rear Cover Sound Quality Thickness

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing apparatuses for outputting sound, such as those using speakers or piezoelectric devices, face challenges including limited design flexibility due to space occupancy, fragility of piezoelectric devices leading to low reliability in sound reproduction, and damage from external impacts.

Innovation Solution

The development of a vibration device and apparatus that includes a vibration member, a rear cover, a first vibration device at a first rear region of the rear cover, and a second vibration device at a second rear region of the rear cover. This configuration enhances sound quality and sound pressure level characteristics while being robust against external impacts.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a speaker or piezoelectric device is applied to output sound, then sound reproduction function is achieved, but the apparatus thickness increases or the device becomes fragile

Engineering Contradiction:
Improvesound reproduction reliabilityVSAvoidapparatus thickness
Core Design Contradiction:
ReliabilityVSLength of moving object

Solution Approach 1:

The patent combines the display panel and vibration plate into a single integrated structure. The display panel serves dual functions as both the visual display component and the sound-generating vibration plate, eliminating the need for separate speaker components and reducing overall apparatus thickness while maintaining sound reproduction capability

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The patent replaces traditional electromagnetic speaker actuators with piezoelectric devices that convert electrical signals directly into mechanical vibrations of the display panel. This substitution enables thinner design while achieving effective sound output through the panel's vibration

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

2Length of moving object

If a piezoelectric device is applied to reduce thickness, then thin profile is achieved, but the device becomes easily damaged by external impact

Engineering Contradiction:
Improveapparatus thicknessVSAvoiddamage resistance
Core Design Contradiction:
Length of moving objectVSReliability

Solution Approach 1:

The patent positions multiple vibration devices at different locations on the rear cover to create a distributed support system. This arrangement provides beforehand cushioning by spreading the mechanical stress and impact forces across multiple points, protecting the piezoelectric elements from concentrated damage while maintaining thin profile

Inventive Principle:
Principle #11Beforehand cushioning (Prior cushioning)

Solution Approach 2:

The patent utilizes the display panel itself as a flexible vibration membrane that can withstand external impacts. The panel's inherent flexibility and distributed structure provide protection to the embedded piezoelectric devices while maintaining the thin design requirement

Inventive Principle:
Principle #30Flexible shells and thin films

3Device complexity

If a single vibration device is used, then device complexity is reduced, but sound quality and sound pressure level are insufficient

Engineering Contradiction:
Improvevibration device structureVSAvoidsound quality
Core Design Contradiction:
Device complexityVSReliability

Solution Approach 1:

The patent divides the sound generation function into multiple segmented vibration devices positioned at different locations on the rear cover. Each device handles specific frequency ranges or spatial zones, and their combined operation produces superior sound quality and pressure level while maintaining relatively simple individual device structures

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent applies vibration devices with different characteristics to different locations on the rear cover. Each location receives a vibration device optimized for its specific position and function, creating local quality variations that collectively enhance overall sound performance without requiring complex individual devices

Inventive Principle:
Principle #3Local quality

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 proposed solution effectively enhances sound quality and sound pressure level characteristics, improves the robustness of the apparatus against external impacts, and maintains a thin profile, addressing the limitations of existing technologies.

Implementation Method 1

a vibration device at a first rear region of the rear cover, and a second vibration device at a second rear region of the rear cover... vibrate the rear cover to generate sound

Methodology Applied
Scientific EffectVibration: Vibration

Implementation Method 2

piezoelectric devices which enable a thin thickness to be implemented... a second vibration device at a second rear region of the rear cover

Methodology Applied
Scientific EffectPiezoelectric effect: Piezoelectric Effect

Data Source

PatentEP4087277B1Apparatus for outputting sound
Publication Date: 2025.04.09 LG DISPLAY CO LTD
  • EP4087277B1 patent drawingFigure 1~2A
  • EP4087277B1 patent drawingFigure 2B~2C
  • EP4087277B1 patent drawingFigure 3~4

AI summary

An apparatus comprises a vibration member, a rear cover at a rear surface of the vibration member, a first vibration device at a first rear region of the rear cover, and a second vibration device at a second rear region of the rear cover.