Backlight Support Member Leg Through PCB Hole

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Direct backlight units in large-sized liquid crystal display devices face issues with luminance uniformity due to deflection of light diffusion plates supported by traditional support members, leading to increased thickness and reduced luminance uniformity.

Innovation Solution

A display device design featuring a reflector with a flat bottom surface and support members with leg portions that project through holes in the printed circuit board, reducing twisting and deflection of the reflector and preventing thickness increase, while maintaining luminance uniformity.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Stability of the object's composition

If a support member with a leg portion is mounted on the reflector to support the light diffusion plate, then the light diffusion plate is supported and deflection is prevented, but the leg portion projects from the back surface of the housing and increases the thickness of the display device

Engineering Contradiction:

Improvestability of light diffusion plateVSAvoidthickness of display device

Core Design Contradiction:

Stability of the object's compositionVSLength of stationary object

Solution Approach 1:

The leg portion of the support member is inserted through a through hole formed in the printed circuit board, nesting the support structure within the existing housing thickness. This allows the support member to stabilize the light diffusion plate without increasing the overall thickness of the display device, as the leg portion passes through the housing rather than projecting from it.

Inventive Principle:

Principle #7Nested doll (Nesting)

2Device complexity

If the light diffusion plate is supported on the housing with end portions in contact, then the structure is simple, but the light diffusion plate deflects and luminance uniformity is reduced

Engineering Contradiction:

Improvesimplicity of support structureVSAvoidluminance uniformity

Core Design Contradiction:

Device complexityVSManufacturing precision

Solution Approach 1:

The support function is segmented between the support member and the housing. The support member with its leg portion provides dedicated support at specific locations where through holes are formed, while the housing provides overall structural support. This segmentation allows the light diffusion plate to be supported at multiple points, preventing deflection and maintaining luminance uniformity without requiring complete contact with the housing.

Inventive Principle:

Principle #1Segmentation

3Ease of manufacture

If the leg portion of the support member projects from the back surface of the housing, then the support member can be easily installed, but the thickness of the display device is increased

Engineering Contradiction:

Improveease of support member installationVSAvoidthickness of display device

Core Design Contradiction:

Ease of manufactureVSLength of stationary object

Solution Approach 1:

The installation approach is changed from projecting outward in the thickness direction to passing through the housing in the lateral direction. The leg portion is inserted through through holes formed in the printed circuit board from the front surface side, utilizing the lateral dimension of the housing rather than extending in the thickness direction. This maintains ease of installation while avoiding thickness increase.

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

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

Enhances the uniformity ratio of luminance by minimizing reflector distortion and preventing thickness increase, ensuring efficient light distribution and assembly efficiency.

Implementation Method 1

a reflector is arranged in the inside of a box-like housing (a frame), and one or a plurality of fluorescent tubes are arranged above the reflector

Methodology Applied

Scientific EffectLight reflection: Reflection

Implementation Method 2

above the fluorescent tube, an optical sheet and a light diffusion plate are arranged

Methodology Applied

Scientific EffectLight diffusion: Scattering

Data Source

PatentUS7408599B2Backlight assembly comprising a support member corresponding to a hole in a printed circuit board and display device having the same

Publication Date: 2008.08.05 PANASONIC INTELLECTUAL PROPERTY CORP OF AMERICA

AI summary

A display device includes a reflector having a flat bottom surface. A leg portion of a support member which supports a light diffusion plate is mounted on the reflector in an erected manner in a state that the leg portion is allowed to pass through a through hole formed in the reflector and a through hole formed in a housing. Further, in fixing a printed circuit board on a back surface side of the housing, when the leg portion is present in the inside of a region of the back surface side of the housing to which the printed circuit board is fixed, a through hole is formed in a region of the printed circuit board which is overlapped to the leg portion, and the leg portion is allowed to pass through the through hole.