Complex Diffuser Plate for Flat Panel Display Brightness and Mura Control

Solution Overview

Problem

Conventional direct backlight LCDs suffer from poor brightness, bulky volume, long assembly time, and the presence of lamp mura, which affects image quality.

Innovation Solution

A flat panel display with a complex diffuser plate comprising multiple layers with different refractive indexes, transmittances, and haze values, separated by air layers, and featuring recesses and protrusions to enhance brightness and eliminate lamp mura, while reducing the number of optical films and assembly time.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Object-affected harmful factors

If a second diffuser plate with higher haze value is used to eliminate lamp mura, then lamp mura is reduced, but brightness is reduced

Engineering Contradiction:

Improvelamp muraVSAvoidbrightness

Core Design Contradiction:

Object-affected harmful factorsVSIllumination intensity

Solution Approach 1:

The patent divides the single diffuser plate into multiple diffuser layers with different haze values. The first diffuser layer has lower haze to maintain brightness, while the second diffuser layer has higher haze to eliminate lamp mura. This segmentation allows each layer to perform its specific function optimally without compromising the other.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different regions of the optical path are assigned different diffusing properties. The first diffuser layer uses material with lower haze for areas requiring brightness, while the second diffuser layer uses material with higher haze for areas requiring uniformity. This local quality differentiation resolves the contradiction between brightness and lamp mura elimination.

Inventive Principle:

Principle #3Local quality

2Reliability

If multiple optical films are added to improve brightness and eliminate lamp mura, then image quality is improved, but device complexity and assembly time increase

Engineering Contradiction:

Improveimage qualityVSAvoidnumber of optical films

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent combines multiple diffuser layers into a single integrated diffuser plate structure. This merging reduces the total number of separate optical films and simplifies the assembly process while maintaining the functionality of eliminating lamp mura and improving brightness uniformity.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The multi-layer diffuser plate structure serves multiple functions simultaneously: it eliminates lamp mura, improves brightness uniformity, and maintains overall brightness. By integrating these functions into a single component, the patent reduces device complexity and assembly time while improving image quality.

Inventive Principle:

Principle #6Universality (Multi-functionality)

3Reliability

If multiple optical films are added to improve brightness and eliminate lamp mura, then image quality is improved, but assembly time increases

Engineering Contradiction:

Improveimage qualityVSAvoidassembly time

Core Design Contradiction:

ReliabilityVSLoss of time

Solution Approach 1:

The patent combines multiple diffuser layers into a single integrated diffuser plate structure. This merging reduces the total number of separate optical films and simplifies the assembly process while maintaining the functionality of eliminating lamp mura and improving brightness uniformity.

Inventive Principle:

Principle #5Merging (Combining)

4Device complexity

If a single diffuser plate is used, then device complexity is reduced, but lamp mura cannot be effectively eliminated

Engineering Contradiction:

Improvestructure simplicityVSAvoidlamp mura

Core Design Contradiction:

Device complexityVSObject-affected harmful factors

Solution Approach 1:

The patent divides the single diffuser plate into multiple diffuser layers with different haze values. The first diffuser layer has lower haze to maintain brightness, while the second diffuser layer has higher haze to eliminate lamp mura. This segmentation allows each layer to perform its specific function optimally without compromising the other.

Inventive Principle:

Principle #1Segmentation

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 achieves uniformly enhanced brightness, eliminates lamp mura, and simplifies the assembly process, thereby improving image quality and reducing costs.

Implementation Method 1

the first diffuser layer and the second diffuser layer have different refractive indexes, transmittances and haze values

Methodology Applied

Scientific EffectRefraction: Refraction

Implementation Method 2

a complex diffuser includes a first and a second diffuser layers combined to each other

Methodology Applied

Scientific EffectDiffusion: Diffusion

Data Source

PatentUS7796210B2Backlight with complex diffusers and flat panel display using the same

Publication Date: 2010.09.14 HANNSTAR DISPLAY CORP

AI summary

A flat panel display includes a backlight module, a liquid crystal display panel, and a complex diffuser plate. The liquid crystal display panel is disposed on the backlight module, and the complex diffuser plate including a first and a second diffusion layers is disposed between the backlight module and the liquid crystal display panel. Furthermore, the first diffusion layer is adjacent to the liquid crystal display panel and the second diffusion layer is adjacent to the first diffusion layer. The first and the second diffusion layers have different refractive indexes, transmittances and haze values, so that optical performance of the flat panel display is improved.