Floating Potential Cooling Plate for Laser Corrosion

Solution Overview

Problem

Conventional semiconductor laser devices face issues with corrosion in the cooling path, leading to inefficiencies in heat dissipation and stability of laser light properties, particularly in high-output applications where large electric currents generate significant heat.

Innovation Solution

A semiconductor laser device with a simpler cooling structure using electrically conductive cooling blocks and a stainless steel cooling plate, where the cooling plate is set at a floating potential to prevent corrosion and maintain stable heat dissipation, employing a circulation path with ion-exchanged water to prevent clogging and ensure uniform laser light properties.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Loss of energy

If conventional cooling structures with aluminum and copper components are used in high-output semiconductor laser devices, then heat dissipation efficiency is improved, but corrosion occurs in the cooling path due to electrochemical reactions between dissimilar metals

Engineering Contradiction:

Improveheat dissipation efficiencyVSAvoidcooling path corrosion resistance

Core Design Contradiction:

Loss of energyVSReliability

Solution Approach 1:

The invention changes the electrical potential parameter of the cooling plate by setting it to a floating potential through electrical insulation, which prevents the electrochemical corrosion reactions that occur when aluminum and copper are electrically connected in the presence of cooling water

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The invention introduces an intermediary measure (electrical insulation) between the aluminum cooling blocks and the stainless steel cooling plate to prevent direct electrical contact, thereby eliminating the galvanic corrosion pathway while maintaining thermal contact through thermal conductive material

Inventive Principle:

Principle #24Intermediary (Mediator)

2Power

If high electric current is applied to achieve high output power, then laser processing capability is improved, but heat generation in the active region increases significantly

Engineering Contradiction:

Improveoutput powerVSAvoidactive region temperature

Core Design Contradiction:

PowerVSTemperature

Solution Approach 1:

The cooling system is segmented into multiple aluminum cooling blocks that contact different regions of the semiconductor laser element, allowing distributed heat extraction from the active region through multiple thermal pathways

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The invention uses a liquid cooling system with cooling water circulating through the cooling plate and cooling blocks to efficiently remove heat from the high-power laser diode array, utilizing fluid convection for heat transfer

Inventive Principle:

Principle #29Pneumatics and hydraulics

3Loss of energy

If aluminum cooling blocks are used for efficient heat dissipation, then thermal management is improved, but electrochemical corrosion occurs due to contact with stainless steel components in the presence of cooling water

Engineering Contradiction:

Improveheat dissipation efficiencyVSAvoidelectrochemical corrosion

Core Design Contradiction:

Loss of energyVSObject-affected harmful factors

Solution Approach 1:

The invention changes the electrical potential parameter of the cooling plate by setting it to a floating potential through electrical insulation, which prevents the electrochemical corrosion reactions that occur when aluminum and copper are electrically connected in the presence of cooling water

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The invention introduces an intermediary measure (electrical insulation) between the aluminum cooling blocks and the stainless steel cooling plate to prevent direct electrical contact, thereby eliminating the galvanic corrosion pathway while maintaining thermal contact through thermal conductive material

Inventive Principle:

Principle #24Intermediary (Mediator)

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 effectively prevents corrosion and maintains stable, uniform laser light properties by suppressing the dissolution of stainless steel components, ensuring efficient heat dissipation and extended operational lifespan of the semiconductor laser device.

Implementation Method 1

a cooling plate (18) made of stainless steel and having a water supply passage (21) and a drain passage (22

Methodology Applied

Scientific EffectThermal conduction: Conduction (thermal)

Implementation Method 2

a circulation device (26) for circulating the cooling water in the semiconductor laser device (10)

Methodology Applied

Scientific EffectFluid flow:

Data Source

PatentEP3171465B1Cooled semiconductor laser device

Publication Date: 2019.09.25 PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO LTD

Figure 1~2
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AI summary

A semiconductor laser device of the present disclosure includes a cooling plate, an insulating sheet, a first cooling block, and a first semiconductor laser element. The conductive cooling plate includes a water supply passage and a drain passage. The insulating sheet is provided to the cooling plate, and includes a first through hole connected to the water supply passage and a second through hole connected to the drain passage. A first cooling block is provided to the insulating sheet, includes therein a first tube connected to the first through hole and the second through hole, and is electrically conductive. The first semiconductor laser element is provided to the first cooling block. The first semiconductor laser element includes a first electrode, and a second electrode opposite to the first electrode. The first electrode is electrically connected to the first cooling block, and the cooling plate is at a floating potential.