Light Guide Plate with Rotated Pyramidal Elements

Solution Overview

Problem

Conventional liquid crystal display devices face issues with biased brightness distribution towards a front visual angle, requiring additional diffusing and prism sheets that increase device thickness and manufacturing costs.

Innovation Solution

A light guide plate with pyramidal diffusing elements arrayed in a predetermined pattern, rotated clockwise or counterclockwise to angle edges 10° to 35° about a reference line, enhances light refractivity towards a liquid crystal panel, reducing the need for separate diffusing and prism sheets.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Illumination intensity

If diffusing sheet and prism sheets are added to correct brightness distribution, then brightness uniformity at front visual angle is improved, but device thickness increases

Engineering Contradiction:

Improvebrightness uniformityVSAvoiddevice thickness

Core Design Contradiction:

Illumination intensityVSLength of moving object

Solution Approach 1:

The patent combines the functions of the light guide plate, diffusing sheet, and prism sheet into a single integrated light guide plate with microstructures on its surface. The microstructures serve both as diffusing elements and prism elements, eliminating the need for separate diffusing and prism sheets while maintaining brightness uniformity at the front visual angle.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The light guide plate is designed to perform multiple functions simultaneously: it guides light from the edge, diffuses light through microstructures on its surface, and redirects light toward the front visual angle using prism-like microstructures. This multi-functional design replaces multiple separate components with a single versatile element.

Inventive Principle:

Principle #6Universality (Multi-functionality)

2Illumination intensity

If diffusing sheet and prism sheets are added to correct brightness distribution, then brightness uniformity at front visual angle is improved, but manufacturing costs increase

Engineering Contradiction:

Improvebrightness uniformityVSAvoidmanufacturing cost

Core Design Contradiction:

Illumination intensityVSEase of manufacture

Solution Approach 1:

The patent combines the functions of the light guide plate, diffusing sheet, and prism sheet into a single integrated light guide plate with microstructures on its surface. The microstructures serve both as diffusing elements and prism elements, eliminating the need for separate diffusing and prism sheets while maintaining brightness uniformity at the front visual angle.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The patent extracts the diffusing and prism functions from separate sheets and integrates them directly into the light guide plate structure. By forming microstructures on the light guide plate surface through molding or etching processes, the design eliminates the need for additional diffusing and prism sheets, thereby reducing part count and manufacturing complexity.

Inventive Principle:

Principle #2Taking out (Extraction)

3Device complexity

If conventional light guide plate is used, then device structure is simple, but brightness distribution is biased away from front visual angle

Engineering Contradiction:

Improvestructure simplicityVSAvoidbrightness distribution

Core Design Contradiction:

Device complexityVSIllumination intensity

Solution Approach 1:

The patent applies local quality by creating microstructures at specific locations on the light guide plate surface. These microstructures are positioned and oriented to locally redirect light toward the front visual angle, creating non-uniform light redirection that compensates for the inherent brightness distribution bias of conventional light guide plates.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The microstructures on the light guide plate surface are designed with asymmetric orientations, particularly with edges angled at specific angles (e.g., 45 degrees) relative to the light source. This asymmetric design causes light to be redirected preferentially toward the front visual angle, correcting the brightness distribution bias without requiring complex additional components.

Inventive Principle:

Principle #4Asymmetry

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 achieves uniform and higher brightness at a front visual angle without additional sheets, reducing device thickness and manufacturing costs while maintaining or exceeding brightness levels achieved with traditional designs.

Implementation Method 1

A light guide plate with pyramidal diffusing elements arrayed in a predetermined pattern, rotated clockwise or counterclockwise to angle edges 10° to 35° about a reference line, enhances light refractivity towards a liquid crystal panel

Methodology Applied

Scientific EffectRefraction: Refraction

Data Source

PatentUS7614773B2Light guide plate and liquid crystal display device having the same

Publication Date: 2009.11.10 SAMSUNG ELECTRONICS CO LTD

AI summary

A light guide plate and a liquid crystal display device having the same. The light guide plate is disposed upstream of a liquid crystal panel to refract light supplied through an edge thereof, toward the liquid crystal panel. In the light guide plate, a plate body is disposed at a side of a light source for supplying light when a supply voltage is applied. A plurality of pyramidal diffusing elements are arrayed in a predetermined pattern on a surface of the plate body. Each of the diffusing elements is rotated clockwise or counterclockwise about an axis extending through a vertex of the diffusing element perpendicularly to the surface of the plate body so that an edge of the diffusing element facing a reference line connecting a central point of the light source to a central point of the plate body is angled 10° to 35° about the reference line.