Laser Optics for Fiber Lasers and YAG Lasers
Laser optics for fiber lasers and YAG lasers are designed to handle the wavelengths, power levels and process conditions found in modern industrial laser systems. The correct optical material, coating and dimensions are essential for efficient transmission, stable beam quality and long service life.
LMI AB supplies lenses, protective windows and other optical components for fiber lasers and YAG lasers. Our range includes optics for a wide variety of machines, laser heads and applications, and we can also help identify the correct component based on the system, dimensions or existing optics.
Laser Optics for Fiber Lasers and YAG Lasers
Fiber lasers and Nd:YAG lasers operate in the near-infrared wavelength range. Many industrial fiber laser systems operate around 1 µm, often approximately 1070 nm, while the fundamental wavelength of an Nd:YAG laser is approximately 1064 nm.
Optical components must be matched to the wavelength and power of the specific laser. Optics designed for applications such as CO2 lasers at 10.6 µm use different materials and coatings and are not directly interchangeable with optics for fiber and YAG laser systems.
It is therefore important to select optics specified for the particular laser system and the process in which the component will be used.
Optical Components for Industrial Laser Systems
The optical path in a laser system may contain several different components depending on the laser source, processing head and application.
Examples of optical components include:
- focusing lenses
- collimating optics
- protective windows and cover glasses
- optical windows
- other wavelength- and system-specific optical components
Each component has a specific function in the optical path. Materials, dimensions and coatings must therefore be matched to the laser wavelength, power, beam characteristics and the specific application.
Materials for Laser Optics
The choice of material has a significant impact on optical transmission, thermal properties, mechanical durability and service life.
Common materials used for optical components in fiber and YAG laser systems include:
BK7 Optical Glass
BK7 is a well-established optical glass with good transmission across a broad wavelength range. The material is used in various optical applications but has more limited thermal properties than, for example, fused silica and is therefore not suitable for all high-energy laser applications.
Fused Silica
Fused silica, often abbreviated as FS, is a widely used optical material in industrial laser systems. It combines high optical transmission with excellent thermal stability and a low coefficient of thermal expansion.
These properties make fused silica suitable for many demanding laser processes where the optics are exposed to high power densities and temperature variations.
Premium Materials – Sapphire and Diamond
For particularly demanding environments and applications, optical components are also available in more advanced materials.
Sapphire
Sapphire is a very hard and scratch-resistant material with good thermal and mechanical stability. It can be an appropriate choice in applications where the optics are exposed to mechanical wear, particles or other demanding environmental conditions.
Diamond
Diamond has exceptional thermal and mechanical properties and can be used in specialised laser and optical applications with extremely high requirements for thermal conductivity and wear resistance.
Due to its high cost, diamond optics are primarily used in particularly demanding or critical applications where their properties justify the investment.
Optical Coatings
Optical components for laser systems are often equipped with specialised coatings. The coating is an important part of the component’s performance and must be matched to the specific wavelength and application.
AR Coatings – Anti-Reflection Coatings
AR coatings are used to reduce reflection losses at optical surfaces and thereby increase transmission through the component.
This is particularly important in laser systems, as even small optical losses can result in unwanted heating and affect system performance. The coating specification must therefore be matched to the laser wavelength and power.
The Correct Optics for the Wavelength and Laser Power
Two optical components with identical dimensions are not necessarily interchangeable. Differences in material, surface quality and optical coating may mean that the components are intended for completely different wavelengths or power levels.
When selecting laser optics, several factors should therefore be considered, including:
- laser wavelength
- laser power and power density
- optical material
- coating
- the component’s function in the optical path
- dimensions and mechanical mounting
- laser process and operating environment
Incorrect optics can cause increased optical losses, heating and reduced process performance and, in the worst case, may damage both the optical component and other parts of the laser system.
Protective Windows – Protecting the Optical Path
Protective windows are used in many industrial laser heads to protect more expensive optical components from spatter, particles, fumes and other contamination generated by the laser process.
Because the protective window is positioned close to the process, it is often a consumable component that needs to be inspected and replaced regularly. A contaminated or damaged protective window can absorb laser energy, become hot and affect both beam quality and process results.
LMI AB supplies a comprehensive range of protective windows for different laser machines and laser heads.
Different Dimensions and Manufacturers
LMI AB supplies laser optics in a wide range of dimensions and designs for different machines and laser heads.
To identify the correct component, the following information is particularly useful:
- machine manufacturer and model
- manufacturer and model of the laser or processing head
- part number or other identification
- diameter of round components
- width × length of rectangular components
- thickness
- laser wavelength and power, if known
A photograph of the existing component or its packaging can also make identification easier.
Cleaning and Maintenance of Laser Optics
Clean optics are essential for stable laser system performance. Particles, dust, oil and other contamination on an optical surface can absorb laser energy and cause localised heating, which may reduce optical performance and, in the worst case, result in permanent damage.
Only cleaning agents and materials suitable for the specific optical component and its coating should be used. Always follow the recommendations provided by the manufacturer of the optics or laser head.
Products commonly used for cleaning laser optics include:
- optical-grade cleaning agents suitable for the component
- lint-free optical cleaning tissues
- cleaning swabs designed for optical components
- other approved cleaning equipment for laser optics
Avoid touching optical surfaces with your fingers. Optics should be handled in an environment that is as clean and dust-free as possible, and opening laser or cutting heads directly in a contaminated production environment should be avoided.
In cases of heavy contamination or uncertainty regarding the correct cleaning method, follow the manufacturer’s instructions or contact LMI AB for advice.
Preventive Maintenance Reduces the Risk of Optical Damage
Regular inspection of protective windows and other optical components is an important part of preventive maintenance for a laser system.
By detecting contamination or damage at an early stage, the risk of a relatively inexpensive consumable component causing damage to more expensive optics further inside the laser head can be reduced.
The required inspection interval depends on the laser process, material, production environment and intensity of equipment use.
Laser Optics for Different Laser Machines and Systems
LMI AB supplies laser optics, protective windows and related optical components for a wide range of industrial laser machines and laser heads.
Our range includes components for equipment from manufacturers including:
Amada · Bystronic · HSG · Precitec · Prima Industries · Trumpf
Product catalogues for several of these manufacturers are also available on this page for customers who already know the type or part number they require.
Can’t Find the Laser Optics You Need?
Not all optical components and variants available from LMI AB are presented on our website.
If you are looking for a specific lens, protective window or other optical component, contact us with as much information as possible about the machine, laser head and existing component.
With the correct information, LMI AB can help identify suitable optics and reduce the risk of ordering the wrong component.
Contact LMI AB about Laser Optics
Do you need laser optics for a fiber laser or YAG laser, or help identifying the correct component?
Contact LMI AB with information about the machine, laser head and optics currently in use. We will help you identify the correct component and provide information about pricing and availability.
