Laser Machining Optics With Sapphire Outermost Elements

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Laser beam-induced contamination of optics in laser processing systems leads to reduced quality and productivity, machine downtime, and additional costs due to thermal focus shifts and potential damage from localized heating.

Innovation Solution

A device for a laser processing system featuring optical elements with a high thermal conductivity coefficient (≥2 W/(m·K)) as the outermost elements to efficiently dissipate heat and prevent damage, allowing for both passive and active cooling, particularly using sapphire optics with a water-cooled heat sink.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If conventional optics with low thermal conductivity are used, then manufacturing cost is reduced, but laser beam-induced damage occurs due to localized heating

Engineering Contradiction:
Improveresistance to laser beam-induced damageVSAvoidmanufacturing cost
Core Design Contradiction:
ReliabilityVSEase of manufacture

Solution Approach 1:

The patent applies local quality by using materials with different thermal conductivity properties at different locations in the optical system. Specifically, the outermost optical element (which is most exposed to contamination and laser-induced heating) is made of material with high thermal conductivity (≥2 W/(m·K)), while inner optical elements can use conventional materials with lower thermal conductivity. This localized application of high thermal conductivity material protects the critical surface from damage while minimizing overall system cost.

Inventive Principle:
Principle #3Local quality

2Temperature

If high thermal conductivity materials are used for outermost optical elements, then heat dissipation is improved, but device complexity increases

Engineering Contradiction:
Improveheat dissipation capabilityVSAvoidoptical system complexity
Core Design Contradiction:
TemperatureVSDevice complexity

Solution Approach 1:

The patent changes the material parameter (thermal conductivity) of the outermost optical element to ≥2 W/(m·K), which fundamentally alters the thermal management characteristics of the system. This parameter change enables more effective heat dissipation from contamination sites without requiring complex active cooling systems, as the high thermal conductivity material passively conducts heat away from critical areas.

Inventive Principle:
Principle #35Parameter changes

3Temperature

If active cooling is implemented, then heat dissipation is enhanced, but device complexity and cost increase

Engineering Contradiction:
Improvecooling efficiencyVSAvoidcooling system complexity
Core Design Contradiction:
TemperatureVSDevice complexity

Solution Approach 1:

The patent enables self-service thermal management by using materials with inherently high thermal conductivity (≥2 W/(m·K)) for the outermost optical elements. These materials passively conduct heat away from contamination sites without requiring external cooling systems. The high thermal conductivity material essentially serves its own cooling function, eliminating the need for complex active cooling infrastructure while maintaining effective heat dissipation.

Inventive Principle:
Principle #25Self-service

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 solution effectively reduces machine downtime and increases productivity by preventing laser beam-induced damage and maintaining optical quality through efficient heat dissipation and active cooling, while also providing flexibility with exchangeable lens cassettes.

Implementation Method 1

a first outermost optical element with respect to a propagation direction of the laser beam is made of a material having a coefficient of thermal conductivity kT of 2 W/(m·K) or more

Methodology Applied
Scientific EffectThermal conduction: Conduction (thermal)

Implementation Method 2

particularly using sapphire optics with a water-cooled heat sink

Methodology Applied
Scientific EffectConvection cooling: Convection

Data Source

PatentEP3898064B1Device for a laser machining system, and laser machining system having a device of this kind
Publication Date: 2022.04.27 PRECITEC GMBH
  • EP3898064B1 patent drawingFigure 1
  • EP3898064B1 patent drawingFigure 2~3
  • EP3898064B1 patent drawingFigure 4

AI summary

The present disclosure relates to a device for a laser machining system (100), comprising laser beam optics for a machining laser beam (10) having an arrangement of optical elements, which are arranged successively in a beam path of the machining laser beam (10). In relation to a propagation direction of the machining laser beam (10), a first outermost optical element (210) of the arrangement of optical elements is made of a material that has a thermal conductivity coefficient k T of 2 W/(m·K) or more.