Dark markings on a pale background is a good way to improve legibility
Aluminum and other metals benefits from this two pass process. The first pass generates a pale background and during the second pass the laser etches a dark marking. The increased contrast is great for improved legibility by human and machine alike.
The checkered pattern you see in the video is called a Data Matrix code, to learn more on the subject consult our guide on Industrial Traceability: How Barcodes Work.
Laser engraving on flat surfaces such as this one can be accomplished with Laserax LXQ lasers. Visit our website for more information on that laser.