Process Date: January 2000

White mark - Marked with 20 watts of laser power at a speed of 30"/s

Dark mark – Marked with 10 watts of laser power at a speed of 2"/s

Because of its resulting highly contrasting marks, anodized aluminum is frequently marked with CO₂ lasers. While Black and colored anodized aluminum are commonplace, clear anodized aluminum is less frequently used. It does, however, offer a unique marking capability - the ability to produce either a light or dark mark, according to laser parameters. In this case, a dark mark resulted from the use of 10 watts of power, while the use of 20 watts resulted in a white mark. This type of mark contrast control is uncommon for CO₂ laser processing.

It is also worth noting that in-between these two marking styles, a "no mark" region exists. In this case, for example, using somewhere between 10 and 20 watts of power will result in no mark at all.