Arc-Shaped Bar Patterns on Diffusion Plate for LCD Backlight
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional diffusion plates in LCD backlight modules do not achieve an ideal diffusion effect, leading to visible illumination shades and requiring multiple films to diffuse light uniformly, with a transmittance of only 60%.
Innovation Solution
A diffusion plate with alternating arc-shaped bar patterns and a second prism-shaped diffusion plate beneath it, optimized with specific height and width ratios and materials like PMMA, PC, and PET, achieving a transmittance of over 75% and improved diffusion.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If the concentration of optical diffusion particles is increased to improve diffusion effect, then the diffusion effect is improved, but the transmittance decreases
Solution Approach 1:
The diffusion plate is divided into multiple regions with different optical diffusion particle concentrations. The first concentration is higher than the second concentration, creating a gradient structure that optimizes both diffusion effect and transmittance in different areas of the plate.
Solution Approach 2:
Different regions of the diffusion plate are assigned different optical diffusion particle concentrations according to their functional requirements. The first region with higher concentration provides stronger diffusion where needed, while the second region with lower concentration maintains higher transmittance, achieving local optimization of optical properties.
2Device complexity
If a single diffusion plate is used to simplify the structure, then the device complexity is reduced, but the diffusion uniformity is insufficient
Solution Approach 1:
The single diffusion plate is segmented into multiple regions with different optical diffusion particle concentrations, creating functional zones that work together to achieve uniform diffusion across the entire plate while maintaining a relatively simple overall structure.
3Quantity of substance
If the transmittance of diffusion plate is increased to improve light transmission, then the light transmission is improved, but the diffusion effect deteriorates
Solution Approach 1:
The diffusion plate uses segmented concentration zones where the first region with higher particle concentration ensures adequate diffusion effect, while the second region with lower particle concentration maintains high transmittance, achieving a balance between the two opposing requirements.
Solution Approach 2:
Different regions are optimized for different functions: the first region prioritizes diffusion effect with higher particle concentration, while the second region prioritizes transmittance with lower particle concentration, allowing each region to perform its specialized function optimally.
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 solution enhances the diffusion effect and brightness uniformity, achieving better light distribution with higher transmittance compared to prior designs, as demonstrated by optical measurements.
Implementation Method 1
a diffusion plate consisting of transparent polymer which is doped with pluralities of optical diffusion particles which can diffuse light generated by cold cathode fluorescent lamps (CCFLs)
Implementation Method 2
When light passes through the patterns 120, the travel direction of light changes hence can reduce impact on display quality resulting from the illumination shade generated by CCFLs
Data Source
AI summary
The invention provides a diffusion plate and a backlight module. The backlight module includes pluralities of light sources, a reflector and a first diffusion plate. The light sources, which are disposed in the reflector, are spatially arranged. The first diffusion plate is disposed on the light sources. There are pluralities of bar-shaped first patterns and second patters, which are arranged in the alternating way, disposed on the emission surface of the first diffusion plate. The contours of first patterns and second patterns are arc shaped. The height of first patterns is H1, and the width is W1. The height of second patterns is H2, and the width is W2. The value of H1/W1 is between 0.4 and 1. The ratio of H2/W2 versus H1/W1 is between 0.6 and 0.9.