How to choose the best fiber laser engraver

Choosing the right laser engraver for your application is not that complicated. If you’re willing to learn, it’s easy to identify what you need by learning the basics of fiber laser engraving.

The first thing to know is that “fiber laser engravers” are not simply laser engraving machines. You may need a fiber laser to engrave metals, but it can also be configured for laser cleaning if that is what you are looking for, this way it can also be used for various laser marking applications.

In this article, you will find answers to the following questions along with the list of the best fiber laser engraver:

• What are the types of fiber lasers?
• How much laser power do you need?
• How do you choose a fiber laser marking system?
• Why choose a fiber laser for metal engraving?
• How does fiber laser technology work?

What are the types of Fiber Lasers? – Best Fiber Laser Engraver

Choosing the right technology for your applications is key to high-quality results. Different types of fiber lasers are made up of a laser source, a laser beam output, a lens configuration, and different parameters of the laser tube. For that reason, there are a wide variety of fiber lasers that offer different benefits.

The laser source

The laser source includes an optical fiber that can be doped with different rare earth elements to generate specific wavelengths. By knowing the laser source and its wavelength, you can quickly tell if a fiber laser is suitable for your application. Let’s look at common examples:

• Ytterbium-doped fiber lasers – Produce a wavelength of 1064 nm, making them ideal for processing metallic materials. This type of laser source is used in the fiber lasers used by Laserax for marking and metal cleaning applications.
• Thulium-doped fiber lasers – Produce a wavelength of 1940 nm and can be used for medical applications as well as laser marking of plastics.
• Erbium-doped fiber lasers: produce a wavelength of 1550 nm and are used primarily in telecommunications. They provide us with high speed internet and voice over IP, but they are not used for laser engraving.

Fiber lasers are widely used due to the different wavelengths they can generate. The first step should be to look for the laser source to see its possible applications. This could help you avoid purchasing a laser system or machine that cannot engrave your material. For example, if you need to mark plastics, acrylics, and other organic materials, you may need a CO2 laser marker.

The Output of the Laser Beam

When buying a laser, you need to observe whether the laser beam is pulsed or continuous. Some industrial laser marking systems can even switch from one mode to another.

Let’s take a closer look at the types of rays:

• Pulsed Lasers – Generate high-energy spikes that are ideal for etching permanent marks or drilling mini holes without melting surrounding areas.
• Continuous Wave Lasers – Generate constant energy levels that are perfect for laser cutting, drilling and welding machines.

Lens Configuration and Laser Parameters

Lens settings and laser parameters can be optimized by laser experts for different materials and manufacturing processes. Lens settings can include focal length, scan speed, spot size, marking distance, etc. The parameters of the laser engraver include the diameter of the beam, the quality of the beam, the length of the pulse, the number of passes, auto-focus and much more.

Laserax offers different optimized settings for its ytterbium-doped fiber lasers depending on the metal to be etched. If you are interested in how laser parameters affect the laser engraving process, you should read this post on laser ablation.

How much laser power do you need?

To know how much laser power you need, you must first know the desired cycle time for the laser marking operation and the surface of an object. The more powerful the laser, the faster the processing. If you’re limited by short cycle times, higher-powered laser engraving machines are a good investment. Otherwise, you can usually go for a low-power laser module.

Apart from the power of the laser, many factors affect the engraving time. These include:

• The font used for the text and serial numbers.
• The size of the engraving area.
• The material to be engraved (for example, aluminum is easier to engrave than steel)
• The option to use a light background to enhance the contrast of barcodes, data matrix codes, and QR codes
• The marking process (for example, deep engraving of VIN numbers takes more time)

Time estimates for laser engraving can give you a rough idea of ​​the laser power you need. But since many factors affect engraving time, you should generally speak to an expert to determine the exact power of the laser module for your application.

Depending on your time requirements, Laserax can offer up to 500W pulsed fiber laser markers to meet challenging cycle times and high precision. A 100 W laser is usually sufficient to meet the time requirements of most industrial applications.

Tips for Choosing a Fiber Laser Marking System

Before choosing a laser marking system, it is usually necessary to gather some information about its manufacturing process. These tips can help you determine what type of system you need, but also how the system should be configured.

• List the materials to be engraved. Although a wide variety of metals can be marked with fiber lasers (such as aluminum, steel, and stainless steel), each alloy has unique properties that affect how the laser beam interacts with the surface.
• Determine the information that should be flagged if you have traceability needs . This information can include weight, part number, mold number, date and time, etc.
• Determine the types of marks. These can include text, alphanumeric characters, logos, and codes such as data matrix codes.
• Determine how much time is available to dial. Even a rough estimate can help you find the right laser power for your needs.
• Start thinking about laser options. Laser engraving solutions can include a laser safety housing, an HMI to easily adjust the laser for different operations, a dust extraction system, an air knife to prevent dust build-up on the lens, and much more.
• Identify the IP rating you need . This is dictated by the environment in which fiber laser engraving machines are embedded. Casting plants, for example, require a higher level of protection than assembly lines. Some lasers have better protection against dust and liquid splashes.
• Identify the electrical certifications required in your country. Like any electrical equipment, if the laser does not meet these requirements, you may be prohibited from installing it. For example, “UL” certification is current in the US; the “CE” in Europe; and the “CSA” in Canada.

Once you have a list of lasers that interest you, this information will help you quickly identify which lasers meet your requirements.

Why choose a fiber laser for metal engraving?

Fiber lasers are not the only option for metal engraving. Other types of lasers (such as Nd: YAG lasers) can produce similar wavelengths and can therefore be used for the same applications. So why choose a fiber laser?

Different lasers can be configured differently and therefore offer unique advantages. Fiber lasers offer the following advantages:

• Optical fibers offer better beam quality (in other words, the laser beam is better focused) due to their light-guiding properties. As a result, fiber lasers are more efficient at etching metals.
• They have low power consumption and a small heat management requirement.
• They are compact.
• They have a low cost of ownership and low maintenance requirements, making them ideal for automated production lines in the work area. Manufacturers do not need to recalibrate them to maintain their efficiency over time.
• The laser source has a high mean time between failures (100,000 hours). This means that fiber lasers can work full time for more than 10 years with the same high-quality results.

How does fiber laser technology work?

Understanding how laser technology works is important to help you make the best decision. To explain how each component works, let’s first review the journey of a laser beam, starting with the laser diodes, the fiber optics, and the hit on the part you want to engrave.

The pump module

The journey of the laser beam begins when the laser diodes emit light. As it passes through the optical fiber, light travels to the gain medium and pumps it with photons which, in turn, excite the photons already in the gain medium. This creates a buildup of energy.

The resonator module

When photons enter the resonator module, they bounce back and forth between two Bragg gratings. A Bragg grating is a piece of fiber optics with lower density stripes that control which wavelengths are reflected and which are not. It acts as a selective mirror.

One of the Bragg gratings is semi-reflective, which means that only photons of specific wavelengths pass through. These photons form the laser beam. For our ytterbium doped fiber lasers, only photons with a wavelength of 1064 nm pass through.

The distribution of the ray      

Before the laser beam creates a permanent mark on the surface of the part, it passes through a lens and sometimes through a beam amplifier, both located inside the laser head. The lens focuses the laser beam in one place, allowing it to generate enough energy for engraving. The beam expander, on the other hand, enlarges the size of the laser beam (usually referred to as the spot size).

A larger beam better tolerates part positioning variations, avoiding adjustments between two jobs. Because most fiber lasers have a low tolerance for part position variations, you should pay attention to this when choosing a fiber laser.

Fiber lasers direct the beam to a specific location on the part using mirrors. These mirrors are controlled by “galvanometer motors” (or galvos), a special type of motor that can move the laser beam very precisely and at high speed. The beam ends its engraving journey when it leaves the laser head to strike the surface.

The final step: choosing a laser

When it comes time to choose, you have to take into account the type of laser source you need and the output of the beam whether it should be pulsed or continuous. It is also important to calculate the marking time that is needed to avoid bottlenecks and make sure you have collected other basic information such as the type of materials, traceability needs, types of marking, laser options, required certifications, etc.

Once you have this, your application requirements are clearer and you only need to run sample tests with different companies that offer laser or cutter marking. This will allow you to make an informed decision and choose the best fiber laser machine and application.

If you are interested in learning more about our products, you can check out our range of laser engraving machines (for turnkey solutions), as well as our OEM laser engravers (for customized solutions with system integrators).