UV Laser vs Fibre Laser Engraver: What's the Difference?

UV lasers break down bonds directly, so minimal heat stress is used when marking. Because of this, no residue of burrs or yellow tinting is left over on the marked materials.

Since UV lasers do not rely on heat marking and use absorption, these lasers can mark materials that are heat sensitive and may be damaged by fibre lasers.
Heat-sensitive materials that a UV laser can mark are:

• Cartons
• Rubber
• Resin
• Bag film
• Plastics
• Very thin metals

A UV laser has a 355 nm laser with an incredibly high absorption rate. This means that even with materials that have high melting points, like glass or metal, the UV laser can still mark them without using high power. Additionally, since the absorption rate is so high, the laser does not damage the material.

The MD-U Series’ UV wavelength is 1/3 the length of a standard laser, which leads to a smaller beam diameter. Because of this, the UV laser only marks precisely on the spot it needs to. Therefore, there is no swelling across the material that could cause deformation.

Additionally, the small spot diameter allows for marking on small products with intricate detailing. Some examples are 2D codes, plastic tubes, gas meter casings, and in-vehicle plastic parts.

Fibre lasers are known for their high output making for quicker production times. The MD-F Series has two choices of outputs, 30W and 50W. With these outputs, the fibre laser can mark, cut, engrave, and anneal materials fast.

For metals like iron that are not highly reflective, the fibre laser can create high contrast marks. Other lasers that have high absorption rates cannot achieve the same effect quickly.

Fibre lasers are a good choice for cutting materials because of their high output. The 3-Axis Fibre Laser MD-F Series has scratch control, which allows for clean cuts. The cutting process moves the fibre laser beam back and forth across a short distance. Since the fibre laser beam moves across a short distance, the energy is focused. This results in speedy processing time and clean cuts.

The MD-F fibre laser achieves high-quality annealing with wobble control. The Wobble control makes the laser move in a circular pattern rather than overlapping single lines. The circular pattern ensures thick characters and concentrated energy.

The high output of 50 W not only marks fast, but it can engrave deeply. The output's high heat digs deep into materials. With the deep engraving control of the MD-F, the focal distance varies for each laser pass. Because of this, the maximum energy density is achieved throughout the marking.

From a foundational standpoint, a UV laser vs a fibre laser differ greatly. UV lasers use ultraviolet light, while fibre lasers use an infrared light. Additionally, the UV laser is 355 nm while the fibre laser is 1090. Since they have different types of light, each laser has a separate process of marking. Fibre lasers use high heat with high output to mark materials while UV lasers use absorption to break down bonds.

A UV laser does not rely on heat for marking, so it can mark heat-sensitive materials without damage. On the other hand, fibre lasers do use heat, so they do not have the capability of marking on heat-sensitive materials without damage. However, fibre lasers may be better for certain metals like iron because of the high output creating high contrast.

When it comes to speed, choosing a UV laser vs a fibre laser depends on the material that you are looking to mark or process. The fibre laser has an output of 50 W, whereas the UV laser has an output of 3 W. Typically this means that the fibre laser would be faster when it comes to marking, cutting, or engraving. However, there are materials, like plastics, that the higher absorption of the UV allows it to mark or engrave faster than the fibre, regardless of the wattage difference.

The 3-Axis UV Laser MD-U Series and the 3-Axis Fibre Laser MD-F Series at KEYENCE both have 3-Axis control. The 3-Axis control allows for both lasers to mark perfectly on any surface, even 3D surfaces. It works by using an adjustable focal point rather than a fixed focal point like other conventional lasers. When a product is under the laser, the focal point can adjust to the part height ensuring an in-focus mark regardless of changing part height or 3D part shapes.

• More in-depth integrations with AI and machine learning.
• Better energy efficiency and sustainability practices.
• Laser source technology is bound to improve with time.
• It will eventually become even more cost-effective.
• More applications with eco-conscious manufacturing and recycling efforts.

The list of applications, use cases, and benefits of these tools is ever-growing. We’re living in a technological era full of innovation, which will only make the laser engraving process all the more relevant. If your organisation is looking to make your way into the territory of deep laser engraving, you want to work with the experts on the matter.

• UV Laser Markers (MD-U Series)
• Fibre Laser Markers (MD-F Series)
• 3-Axis Hybrid Laser Marker (MD-X Series)

Most consumers won’t settle for less, which means manufacturers will need to keep up with quality standards found in the most recent technology. Traditional methods of laser marking food packaging, car parts, and many other common items are still very relevant.