Light Emitting Device Via Heat Dissipation

Solution Overview

Problem

As light emitting elements increase in output level, they generate more heat, necessitating a light emitting device with improved heat dissipation capabilities.

Innovation Solution

A light emitting device is designed with a substrate that includes a base member, wiring portions, and a reflective member, featuring a recessed portion and vias for enhanced heat dissipation, where the via connects the wiring portions to facilitate heat transfer and improve joining strength.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Power

If light emitting elements increase in output level, then light output is improved, but heat generation increases

Engineering Contradiction:

Core Design Contradiction:

PowerVSTemperature

Solution Approach 1:

The patent converts the harmful heat generated by high-output light emitting elements into a beneficial feature by designing a substrate that actively utilizes this heat for solder melting and reflow soldering processes. The substrate's thermal properties are optimized so that the heat from the light emitting element becomes a useful resource for manufacturing rather than a harmful byproduct.

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

Solution Approach 2:

The patent changes the thermal parameters of the substrate by controlling its thickness and material composition. The substrate is designed with specific thickness ranges (0.5-2.0mm) and thermal conductivity characteristics to optimize heat transfer from the light emitting element to the solder, transforming the thermal management approach from passive dissipation to active utilization.

Inventive Principle:

Principle #35Parameter changes

2Temperature

If a via is formed to connect wiring portions for heat dissipation, then heat dissipation is improved, but structural integrity may be compromised

Engineering Contradiction:

Core Design Contradiction:

TemperatureVSStrength

Solution Approach 1:

The patent applies local quality by forming the via only in specific regions where heat dissipation is most needed, rather than uniformly throughout the substrate. The via connects the first wiring portion to the second wiring portion at strategic locations, providing localized thermal management while preserving overall structural integrity.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The via acts as an intermediary thermal pathway between the first wiring portion and the second wiring portion. It provides a controlled thermal bridge that enables heat transfer from the light emitting element through the substrate without creating weak points that would compromise structural integrity.

Inventive Principle:

Principle #24Intermediary (Mediator)

3Temperature

If a recessed portion is added to the substrate, then heat dissipation and joining strength are improved, but device complexity increases

Engineering Contradiction:

Core Design Contradiction:

TemperatureVSDevice complexity

Solution Approach 1:

The recessed portion is designed to serve multiple functions simultaneously: it acts as a heat sink to improve thermal management, provides a mechanical interlocking feature to enhance joining strength with the light emitting element, and creates a cavity for solder placement. This multi-functionality reduces the need for separate components, thereby limiting the increase in device complexity.

Inventive Principle:

Principle #6Universality (Multi-functionality)

Solution Approach 2:

The patent merges the heat dissipation function and the mechanical mounting function into a single integrated substrate structure. The recessed portion combines thermal management capabilities with structural support and joining features, eliminating the need for separate heat sinks and mounting brackets.

Inventive Principle:

Principle #5Merging (Combining)

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 effectively enhances heat dissipation and joining strength, ensuring efficient thermal management and reliable mounting of the light emitting device.

Implementation Method 1

The base member has a via in contact with the first wiring portion, the second wiring portion, and the third wiring portion

Methodology Applied

Scientific EffectHeat transfer: Conduction (thermal)

Data Source

PatentEP3872874B1Light emitting device

Publication Date: 2023.06.07

Figure 1A~1C
Figure 2A~2B
Figure 3

AI summary

A light emitting device includes a substrate including a base member including a front surface, a rear surface opposite to the front surface, a bottom surface perpendicular to the front surface, and a top surface opposite to the bottom surface, a first wiring portion located on the front surface, and a second wiring portion located on the rear surface; a light emitting element electrically connected with the first wiring portion; and a first reflective member covering a lateral surface of the light emitting element and the front surface of the base member. The base member has a recessed portion opened on the rear surface and the bottom surface. The substrate includes a third wiring portion covering an inner wall of the recessed portion and electrically connected with the second wiring portion, and a via in contact with the first wiring portion, the second wiring portion and the third wiring portion.