Light Source Module FPC Heat Dissipation via Via-Hole
Solution Overview
Problem
Corner-illumination type backlight assemblies face challenges with complex wiring and connectors due to separate PCBs, increased bezel size, and hot spots from concentrated heat sources, which affect image quality and overall thickness.
Innovation Solution
A light source module with a flexible printed circuit board (FPC) featuring a light emitting chip, a substrate, and a heat dissipating part that extends through a via-hole to contact the substrate, using metal materials for enhanced heat dissipation, and a protective portion to enclose the light source, reducing the need for separate PCBs and mold structures.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If separate and multiple PCBs are disposed at adjacent sides of the light guide plate to drive the LED, then the LED can be driven at corner portions, but the wiring and connectors become complicated
Solution Approach 1:
The patent combines multiple separate PCBs into a single integrated PCB structure that extends along adjacent sides of the light guide plate. The circuit board includes first and second portions disposed at different sides and a connection portion connecting them, merging multiple circuit boards into one unified structure. This reduces wiring complexity and connector requirements while maintaining the ability to drive LEDs at corner portions.
2Adaptability or versatility
If separate and multiple PCBs are disposed at adjacent sides of the light guide plate, then the LED can be driven, but the bezel size increases
Solution Approach 1:
The integrated PCB structure merges multiple separate circuit boards into one unified board that follows the contour of the light guide plate's adjacent sides. This consolidation reduces the overall space required for circuit board accommodation, thereby reducing the bezel size while still enabling LED driving at corner portions.
3Use of energy by moving object
If the light source is disposed at a corner portion to reduce occupied area, then light efficiency increases, but heat is focused on a particular area causing hot spots
Solution Approach 1:
The patent extracts the heat dissipation function from the standard PCB structure by providing a dedicated heat dissipation structure that extends from the PCB toward the light guide plate. This separate heat dissipation path removes heat away from the concentrated LED corner location, preventing hot spots while maintaining the space-efficient corner illumination configuration.
4Reliability
If a standard PCB structure is used with thick insulating layers, then electrical insulation is adequate, but the overall thickness of the light source module increases
Solution Approach 1:
The patent applies local quality by making the insulating layer thickness non-uniform: it is thinner at the light emitting chip portion where space is critical and thicker at other portions where electrical insulation is sufficient. This localized variation in insulating layer thickness reduces the overall module thickness while maintaining adequate insulation where required.
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 simplifies wiring, reduces bezel size, prevents hot spots, and efficiently dissipates heat, thereby improving image quality and minimizing the overall thickness of the light source module.
Implementation Method 1
a heat dissipating part which extends from the light emitting chip and contacts the substrate
Implementation Method 2
the metal layer of the FPC and the substrate may be pressed together at a high temperature and a high pressure to fix the metal layer of the FPC and the substrate to each other
Data Source
AI summary
In a light source module and a backlight assembly having the light source module, the light source module includes a flexible printed circuit board; a light source part on an upper surface of the flexible printed circuit board and including a light emitting chip; a substrate on a lower surface of the flexible printed circuit board; and a heat dissipating part which extends from the light emitting chip and contacts the substrate.