1. Printing method: Make the cutting head move from top to bottom, and carry out laser beam printing on the plastic plate, and the focus point is the smallest printing diameter.
2. Blue spark method: Remove the nozzle, blow air, and hit the pulse laser on the stainless steel plate, so that the cutting head moves from top to bottom until the maximum blue spark is the focus.
3. Inclined plate method: Use a plastic plate inclined at an angle to the vertical axis to pull it horizontally, and find the minimum point of the laser beam as the focus.

Because the laser power density has a great influence on the cutting speed, the choice of the focus position is particularly important, and don’t stare at the laser processing operation.