Edge Light Backlight Unit with Perforated Reflective Plate
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing edge light type backlight units for LCDs face challenges in achieving high luminance while maintaining a thin profile, as they often have complex support structures that hinder the reduction of the light guide box thickness and suffer from decreased luminance due to lower opening ratios of pixels in high-definition displays.
Innovation Solution
The proposed edge light type backlight unit incorporates a light guide plate, a rear-side reflective plate, a perforated reflective plate with fine holes, and a circular polarization reflection film, where the perforated reflective plate has a depolarization degree of 60% or less on its emission surface, and the ratio of the thickness to the opening diameter of the holes is 2 or greater, allowing for efficient light reuse and improved luminance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If a complex support structure is used to hold the light guide box, then the structural stability is improved, but the thickness of the backlight unit increases and weight increases
Solution Approach 1:
The patent removes the complex support frame structure from the light guide box, extracting only the essential light guiding function. The light guide box is designed without additional support structures, achieving thickness reduction while maintaining structural integrity through optimized optical path design.
Solution Approach 2:
The light guide box employs thin film structures and flexible design elements to replace rigid support frames. This allows the maintenance of structural stability with significantly reduced thickness, as the thin film structures provide sufficient mechanical support while minimizing added bulk.
2Measurement precision
If the opening ratio of pixels is reduced for high-definition display, then the display resolution is improved, but the luminance of the backlight decreases
Solution Approach 1:
The patent optimizes the optical parameters of the light guide box, including the refractive index distribution, hole patterns, and reflective surface characteristics. These parameter changes enhance light extraction efficiency and luminance uniformity, compensating for the reduced pixel opening ratio in high-definition displays.
Solution Approach 2:
The light guide box utilizes composite material structures combining different optical materials with complementary properties. This composite approach improves light guiding efficiency and luminance output while maintaining the high pixel density required for high-definition display.
3Illumination intensity
If multiple reflective plates and films are added to improve luminance, then the light utilization efficiency is improved, but the device complexity increases
Solution Approach 1:
The patent integrates multiple reflective functions into a unified light guide box structure. The reflective plates and films are strategically positioned and combined to work synergistically, improving luminance through enhanced light recycling without requiring separate complex subsystems for each reflective element.
Solution Approach 2:
The light guide box is designed as a multi-functional component that simultaneously performs light guiding, light reflecting, light diffusing, and structural support functions. This universal design reduces the need for additional separate components, maintaining simplicity while achieving high luminance through efficient light management.
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 configuration enhances the luminance of light incident on the liquid crystal panel while reducing the thickness of the backlight unit, effectively addressing the need for higher luminance and thinner designs in LCDs.
Implementation Method 1
a circular polarization reflection film which is disposed on the emission-side surface side of the perforated reflective plate
Implementation Method 2
both the light guide plate-side surface and the emission-side surface are reflection surfaces and a depolarization degree of the emission-side surface is 60% or less
Implementation Method 3
a light guide plate which has an end surface, on which light emitted from the light source is incident, and propagates the light incident from the end surface
Data Source
AI summary
An edge light type backlight unit includes: a light source; a light guide plate which has an end surface, on which light emitted from the light source is incident, and propagates the light incident from the end surface; a rear-side reflective plate which is disposed on a surface side of the light guide plate; a perforated reflective plate which is disposed on a surface side of the light guide plate and has a plurality of fine holes, which penetrate from a surface on the light guide plate side to an emission-side surface facing the light guide plate-side surface and transmit light, and in which both the surface and the surface are reflection surfaces and a depolarization degree of the surface is 60% or less; and a circular polarization reflection film which is disposed on the surface side of the perforated reflective plate.