Backlight Module Optical Plate Extension for Light Leakage Prevention

Solution Overview

Problem

The existing edge-type LED backlight modules in liquid crystal displays suffer from light leakage due to deformation and warping of the light guide plate, leading to uneven brightness and increased production costs and assembly complexity, as they require a reflecting film to prevent light emission through holes in the frame.

Innovation Solution

A backlight module design featuring a light guide plate with an optical plate and optical coating layer, where the optical plate extends towards the LED backlight source, eliminating the need for a reflecting film by using a diffusion film, prism film, or polarizer with a light reflecting or absorbing material coating on its surface to prevent light leakage through the frame's holes.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Object-affected harmful factors

If a reflecting film is added to prevent light leakage through frame holes, then light leakage is prevented, but production cost and assembly complexity increase

Engineering Contradiction:

Improvelight leakageVSAvoidassembly complexity

Core Design Contradiction:

Object-affected harmful factorsVSDevice complexity

Solution Approach 1:

The patent combines the light guiding function and light reflection function into a single integrated optical plate structure. The optical plate includes a light guiding portion that guides light from the LED backlight source and an extension portion that extends to the light incident end of the light guide plate, eliminating the need for separate reflecting films and reducing assembly steps.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The optical plate serves multiple functions: it acts as both a light guiding element and a light reflecting element. The extension portion of the optical plate reflects light that would otherwise leak through the frame holes, while the main body guides light into the light guide plate, reducing the number of components needed.

Inventive Principle:

Principle #6Universality (Multi-functionality)

2Object-affected harmful factors

If a reflecting film is added to prevent light leakage through frame holes, then light leakage is prevented, but production cost increases

Engineering Contradiction:

Improvelight leakageVSAvoidproduction cost

Core Design Contradiction:

Object-affected harmful factorsVSEase of manufacture

Solution Approach 1:

The patent combines the light guiding function and light reflection function into a single integrated optical plate structure. The optical plate includes a light guiding portion that guides light from the LED backlight source and an extension portion that extends to the light incident end of the light guide plate, eliminating the need for separate reflecting films and reducing assembly steps.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The optical plate serves multiple functions: it acts as both a light guiding element and a light reflecting element. The extension portion of the optical plate reflects light that would otherwise leak through the frame holes, while the main body guides light into the light guide plate, reducing the number of components needed.

Inventive Principle:

Principle #6Universality (Multi-functionality)

3Object-affected harmful factors

If the optical plate extends to the light incident end, then light leakage is prevented, but the optical plate area increases

Engineering Contradiction:

Improvelight leakageVSAvoidoptical plate area

Core Design Contradiction:

Object-affected harmful factorsVSArea of stationary object

Solution Approach 1:

The optical plate has different structural characteristics in different regions: the light guiding portion has a first thickness, while the extension portion has a second thickness that is different from the first. This local variation in thickness allows the extension portion to effectively reflect light and prevent leakage while minimizing the overall area and material usage.

Inventive Principle:

Principle #3Local quality

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 design effectively prevents light leakage without additional reflecting films, reducing production costs and simplifying assembly by ensuring light is directed into the light guide plate, maintaining even brightness and reducing manufacturing complexity.

Implementation Method 1

The optical coating layer is formed by a light reflecting material or a light absorbing material

Methodology Applied

Scientific EffectLight reflection: Reflection

Implementation Method 2

The optical coating layer is formed by a light reflecting material or a light absorbing material

Methodology Applied

Scientific EffectLight absorption: Absorption (EM radiation)

Implementation Method 3

The optical plate is a diffusion film, a prism film, or a polarizer

Methodology Applied

Scientific EffectLight diffusion: Scattering

Implementation Method 4

The optical plate is a diffusion film, a prism film, or a polarizer

Methodology Applied

Scientific EffectLight refraction: Refraction

Data Source

PatentUS8641261B2Backlight module

Publication Date: 2014.02.04 AU OPTRONICS CORP

AI summary

A backlight module is disclosed. The backlight module includes a light guide plate, a backlight source, an optical plate, and an optical coating layer. The light guide plate has a light emitting surface and a light incident end. The light incident end is located at an adjacent side of the light emitting surface. The backlight source is disposed corresponding to the light incident end and generates lights emitting to the light incident end. The optical plate is disposed above the light emitting surface. The optical plate includes an extension portion extending disposed above the backlight source. The optical coating layer is formed on a surface of the extension portion.