LCD Panel Acoustic Coupling Through Backlight Air Cavities
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing liquid crystal display (LCD) panels face challenges in producing sound due to the presence of a backlight source that cannot be shielded, resulting in a large distance that hinders efficient vibration transmission and prevents sound generation.
Innovation Solution
A display apparatus with a liquid crystal display panel and a backlight module, featuring a sound board and sound driver, where the sound driver is fixed to the backlight module to drive it to vibrate, transmitting vibrations through sealed air cavities to the liquid crystal display panel, allowing sound production.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If a backlight source is provided behind the LCD panel for uniform illumination, then the display achieves uniform brightness, but the backlight source cannot be shielded and creates a large distance that hinders efficient vibration transmission
Solution Approach 1:
The backlight module is segmented into multiple independent light emitting units arranged in an array, allowing selective activation and positioning. This segmentation enables the sound driver to be positioned closer to specific viewing areas while maintaining overall illumination uniformity through coordinated operation of multiple light units.
Solution Approach 2:
A sound board is introduced as an intermediary component between the sound driver and the LCD panel. The sound driver vibrates the sound board, which then transmits vibrations to the LCD panel through acoustic coupling, bypassing the need for direct attachment to the backlight source and enabling efficient sound transmission despite the distance constraint.
2Stability of the object's composition
If the LCD panel has multiple independent and stacked layers with a backlight source behind it, then the display structure is maintained, but the sound driver cannot be installed in the LCD panel
Solution Approach 1:
The sound driver is merged with the backlight module structure, specifically positioned behind the LCD panel in close proximity to the light emitting units. This integration allows the sound driver to be installed without disrupting the existing multi-layer LCD structure, as it utilizes the available space within the backlight assembly.
Solution Approach 2:
The sound board serves as a mediator that couples the sound driver to the LCD panel without requiring direct installation within the panel's multi-layer structure. This intermediary approach preserves the structural integrity of the LCD while enabling sound generation functionality.
3Length of moving object
If speakers are placed at the bottom or rear portion of the display apparatus, then the ultra-thin appearance and installation location constraints are satisfied, but the sound and image positions are separated leading to poor audio-visual experience
Solution Approach 1:
The sound generation function is moved from the traditional bottom or rear spatial dimension to the rear proximity dimension directly behind the display panel. By positioning the sound driver close to the light emitting units in the depth dimension rather than at the bottom edge, the system achieves both thin profile and synchronized audio-visual experience through spatial correspondence between image and sound sources.
Solution Approach 2:
The backlight module is given multi-functionality by integrating sound generation capability alongside its illumination function. The same structural space housing the light emitting units also accommodates the sound driver, allowing a single component to serve dual purposes and eliminate the need for separate speaker assemblies that would compromise the thin design.
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 sound generation directly from the LCD panel, providing an integrated audio-visual experience by overcoming the limitations of the backlight source and enhancing sound transmission efficiency.
Implementation Method 1
a vibration output terminal of the sound driver is fixed to a surface of the sound board away from the backlight module, and the sound driver is configured to drive the sound board to vibrate through the vibration output terminal
Implementation Method 2
A first sealed air cavity is formed inside the liquid crystal display panel. The backlight module is located on a side of the liquid crystal display panel and forms a second sealed air cavity with the liquid crystal display panel
Data Source
AI summary
Provided is a display apparatus. The display apparatus includes: a liquid crystal display panel and a backlight module, wherein a first sealed air cavity is formed inside the liquid crystal display panel, and the backlight module is located on one side of the liquid crystal display panel and forms a second sealed air cavity with the liquid crystal display panel; and a sound production board and a sound production exciter, wherein the sound production board is fixed onto the surface of the backlight module away from the liquid crystal display panel, a vibration output terminal of the sound production exciter is fixed onto the surface of the sound production board away from the backlight module, and the sound production exciter is used for exciting, by means of the vibration output terminal, the sound production board to vibrate, so as to drive the backlight module to vibrate.