You measure the distance at each speed and fill in the table accordingly. The LightBurn Scanning Offset Adjustment is half the measured distance, with an Initial Offset parameter to adjust the starting point of the first scan line.

Peering at it through a measuring magnifier suggests the offset is a bit over 0.2 mm at 400 mm/s, corresponding to a 500 µs delay between laser turn-on in the rightward direction and turn-off in the leftward direction. The laser spot diameter is, at absolute best, about 0.2 mm on the focal plane, with the actual engraved line being smaller due to the energy distribution across the beamwidth and the power required to visibly damage the material, so a 0.1 mm interval should result a little bit of overlap between adjacent scan lines.Ī closer look shows the serrated edges on the left and right sides of the engraved squares: Offset cal – zero offset – detail The “Interval” value is the vertical (Y-axis) scan line spacing. LightBurn can produce a calibration coupon (on Trolase laminated acrylic) to help explore the multidimensional parameter space: Offset cal – zero offset – overview The problem arises from the finite delay between the controller turning the laser beam on and the rise time of the death ray energy at the focal point. The fuzzy edges engraved on the acrylic test sample showed the need for scan offset adjustment: Please Close The Gate – acrylic test piece

Lightburn laser software y axis offset