Alternating Light Guide Plates for Backlight Unit Brightness Uniformity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Large-sized LCDs face issues with non-uniform brightness and clarity due to brightness gradients, leading to the generation of bright or dark lines, which complicates the development of backlight units for achieving excellent image quality.
Innovation Solution
A backlight unit design featuring alternately arranged light guide plates and LED packages with a symmetrical structure, where light sources emit light towards the central region, and LED packages are mounted on a substrate with circuit wiring, including a lead terminal with an 'L' shaped structure for improved heat dissipation and uniform light distribution.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Area of stationary object
If multiple light guide plates are disposed in parallel to illuminate large-sized LCDs, then the display area is increased, but brightness uniformity deteriorates due to brightness gradients
Solution Approach 1:
A reflective plate is positioned at the center to reflect light from one light guide plate to another, merging the illumination paths. This causes light to travel through multiple light guide plates sequentially, mixing the light paths and eliminating brightness gradients that occur when plates are simply arranged in parallel.
Solution Approach 2:
The reflective plate creates a continuous light path that traverses through multiple light guide plates in sequence rather than independently. Light from a single source continues to illuminate through reflected paths across multiple plates, ensuring uniform brightness distribution across the entire large display area.
2Area of stationary object
If light guide plates are arranged in parallel for large-sized LCDs, then the display coverage is improved, but clarity deteriorates due to generation of bright lines or dark lines
Solution Approach 1:
The reflective plate merges the light paths from multiple light guide plates into a unified illumination pattern. By reflecting light between plates, the system eliminates the distinct boundaries that create bright and dark lines, achieving seamless coverage across the entire display area without clarity degradation.
3Illumination intensity
If light guide plates are disposed spaced apart with symmetrical structure, then light mixing in central region is improved, but device complexity increases
Solution Approach 1:
While the overall arrangement of light guide plates is symmetrical, the reflective plate is positioned asymmetrically at the center to create the light mixing effect. This asymmetric element within a symmetric framework achieves uniform light distribution without requiring complex arrangements of multiple independent light sources or intricate optical systems.
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 design enhances brightness uniformity and clarity, reducing the occurrence of bright or dark lines, thereby improving image quality and simplifying manufacturing processes.
Implementation Method 1
a plurality of light guide plates and a plurality of LED packages arranged alternately with the light guide plates, respectively, in which light emitted from the LED packages is incident on the light guide plates
Implementation Method 2
a plurality of light guide plates and a plurality of LED packages arranged alternately with the light guide plates, respectively, in which light emitted from the LED packages is incident on the light guide plates
Data Source
Figure 1~2
Figure 3A~3B
Figure 4~5
AI summary
There is provided a backlight unit. The backlight unit is configured to include: a plurality of light sources; a plurality of light guide plates being arranged alternately with the light sources so that light emitted from the light sources is incident; and a chassis receiving the light sources and the light guide plates, wherein the plurality of light guide plates are disposed to be spaced apart from each other, being symmetrical to each other in order to face the central region of the chassis, a pair of light guide plates opposed to each other on the central region being connected to each other so that the light therefrom is mixed.