Sometimes letters get fuzzy, elongated, or foreshortened because the printing head cannot take into account the surface topology. And even flat surfaces present problems as the laser’s spot size varies from the edge of the marking area to the center.

To account for these issues, engineers at Keyence developed the ML-Z9500 Series of CO2 laser markers. It can determine and adjust to the correct focal length for any surface within its 42-mm range. This eliminates the need for complex indexing mechanisms that change the height of the marking unit as the distance to the surface changes. It also has an X, Y, and Z scanner that controls the marking laser in three dimensions by adjusting its focal point. This lets the marker put clear letters and symbols on stepped surfaces, cylinders, and cones, even if these shapes are moving. The controls also have a warm-up feature that ensures the 30-W laser has reached its stable operating power before beginning to mark, so there are no variations in lettering from the beginning of the process through to the end.

Laser marking