Difference Between UV Laser and Fibre Laser Engraving Machines

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 high-powered lasers.
Heat-sensitive materials that a UV laser can mark are:

• Cartons
• Rubber
• Resin
• Bag film

A UV laser has a 355 nm laser with an incredibly high absorption rate. Meaning 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 ⅓ of the size of a standard laser wavelength. 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.

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 50W 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 an ultraviolet laser while fibre lasers use an infrared laser. Additionally, the UV laser is 355 nm while the fibre laser is 1090. Since they have different types of lasers, 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. But, 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 how fast you want production to be. Fibre lasers have a high output of 50W while UV lasers have an output of 3W. Because of this, fibre lasers are significantly faster. Fibre lasers are optimal for big production marking, cutting, or engraving projects that need efficiency.

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 auto-focused focal point rather than a fixed focal point like other conventional lasers. When a material is under the laser, the focal point automatically adjusts for the target area depending on the material's size and height and how it is placed in the production line. Because of this, both the fibre laser and the UV laser can ensure uniform and distortion-free marking.