Laser marking machine selection

Lasers can be used for marking and processing various products, but no single laser type is suitable for all applications. When exposed to light, all objects undergo “reflection,” “absorption,” and “transmission.” As a result, the performance of fiber, CO₂, and UV laser marking machines varies depending on the application and material.

The greater the “reflection” and “transmission,” the harder it is for the object’s temperature to rise, making processing more difficult. The more “absorption,” the higher the processing efficiency.

The most important difference between fiber, CO₂, and UV laser marking machines lies in the wavelength of the light they produce. Shorter wavelengths generally have more energy and higher absorption rates than longer wavelengths. Therefore, the wavelength of a laser affects its ability to mark certain materials.

Below are the characteristics and marking examples of different wavelength types.

The wavelength of a fiber laser is 1090 nm, making it an infrared (IR) laser. Fiber lasers can mark a wide range of materials and are particularly well-suited for marking metal objects. Their high power makes them ideal for annealing and engraving applications. However, they cannot mark transparent objects, as infrared light passes directly through them.

CO2 lasers have a wavelength that is 10 times longer than standard wavelength systems. They excel at marking paper, resin, wood, rubber, and transparent materials such as glass and PET. However, it is not possible to mark metals with a CO2 laser because the laser light is not absorbed by the object.

UV lasers use a highly absorbable wavelength (355 nm) to mark parts. This high absorption rate allows UV lasers to perform “cold marking,” meaning no additional thermal stress is applied during marking. As a result, UV lasers are an ideal choice for applications requiring high contrast or minimal product damage.

Fiber lasers can quickly mark most materials and typically produce strong contrast on metals. However, they cannot mark transparent materials and may occasionally damage the surface being marked. UV lasers achieve high contrast on resins and offer the unique advantage of creating damage-free marks. CO₂ lasers mark targets through thermal burning, making them ideal for marking wood, paper, ceramics, and transparent materials.