Backlight Unit Light Path Control Patterns for Display Uniformity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Liquid crystal display devices face challenges in reducing the thickness of the backlight unit while maintaining image quality, as insufficient optical gaps between light sources and the display panel can lead to decreased image quality and increased manufacturing costs.
Innovation Solution
The implementation of light path control patterns and reflective layers with varying reflective characteristics to increase the path length of emitted light, allowing for improved image quality without increasing the number of light sources, by optimizing the ratio of specularly and diffusely reflected light.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Length of stationary object
If the thickness of the backlight unit is reduced, then the thickness of the liquid crystal display device is reduced, but the optical gap between the light source and the display panel is insufficient, causing image quality to drop
Solution Approach 1:
The patent applies local quality by creating light path control patterns with different reflective characteristics in different regions. The first light path control patterns have a ratio of specularly reflected light to diffusely reflected light between 1:3 and 1:1, while the second light path control patterns have a ratio greater than 1:1. This spatial variation in reflective properties allows the thin backlight unit to maintain adequate optical path length and image quality.
Solution Approach 2:
The patent changes the optical parameters of the light path control patterns by controlling the ratio of specularly reflected light to diffusely reflected light. By adjusting this ratio parameter differently in the first and second light path control patterns, the system optimizes light distribution and path length within the reduced thickness constraint, preventing image quality degradation.
2Manufacturing precision
If the number of light sources is increased to improve image quality, then the image quality of the backlight unit is improved, but the manufacturing cost increases
Solution Approach 1:
Instead of increasing the number of light sources, the patent improves image quality by optimizing the local reflective properties of the light path control patterns. The first and second light path control patterns create different light distribution characteristics in their respective regions, achieving uniform image quality across the display panel without additional light sources.
Solution Approach 2:
The patent introduces light path control patterns as intermediary elements between the light sources and the display panel. These patterns mediate the light distribution by controlling specular and diffuse reflection ratios, thereby improving image quality without requiring additional light sources or increasing manufacturing complexity.
3Ease of manufacture
If the distance between light sources is increased to reduce the number of light sources, then the manufacturing cost is reduced, but the image quality may be affected
Solution Approach 1:
The patent compensates for increased distance between light sources by optimizing the local reflective characteristics of the light path control patterns. The first patterns with lower specular reflection ratios and the second patterns with higher specular reflection ratios work together to maintain uniform light distribution even when light sources are spaced farther apart, preserving image quality while reducing component count.
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 approach enhances light uniformity and increases the distance between light sources, thereby improving image quality while reducing the thickness and number of light sources in the backlight unit.
Implementation Method 1
among a reflected light by the first light path control pattern, a ratio of specularly reflected light is smaller than a ratio of diffusely reflected light
Implementation Method 2
among a reflected light by the second light path control pattern, a ratio of specularly reflected light is greater than a ratio of diffusely reflected light
Data Source
AI summary
A backlight unit for a display device includes a light path control pattern disposed over a light source and including portions having different types of reflective characteristic and a reflective layer disposed on a substrate where the light source is mounted and including portions having different types of reflective characteristic, a light guide distance of a light emitted from the light source can be increased and a light uniformity can be maintained, so that as a light can be supplied to each area evenly while increasing a distance between the light sources and reducing the number of the light sources, an image quality of the backlight unit can be enhanced.