This view shows the banding effect on 0.06-in. diameter 304 stainless steel, thanks to marking with a single-mode fiber laser.
The fiber-laser marker has become commonplace for mainstream marking applications, providing excellent high speed contrast marking of steels and plastics, as well as materials micromachining, including cutting, drilling, scribing and ablation. Lasers with better beam quality can mark or machine faster, and provide better feature resolution and improved process quality.
The best beam quality is found in single-mode fiber-laser markers, which offer considerable processing advantages when compared with standard beam-quality fiber-laser markers, and can challenge premium 532 nm and 355 nm laser markers.
What is “beam quality”? There are a number of critical laser parameters that define a fiber laser’s processing capability, including peak power, frequency range, pulse width, and beam quality. Beam quality may not be the most familiar parameter, but it has a significant impact and should be considered much more closely than it has been in the past: a laser with better beam quality can remove material much faster, with better resolution and improved quality.
Beam quality — known as M2 — is defined as the ratio of the beam that the laser produces to that of a perfect laser, so a perfect laser has an M2 of 1. Laser markers with high beam quality (M2 of less than 1.3) can produce a focused optical spot size down to 20 microns, making them particularly well suited for scribing and cutting tasks on a wide variety of materials, including alumina, silicon, copper, and aluminum foils.
In addition, the use of selectable pulse width waveforms with different pulse widths and peak power characteristics enables tuning of the removal rate and quality of the feature surface.