There are five simple ways to determine the focus position in the industrial production of laser cutting machine:
(1) Blue Spark Method: Remove the nozzle, blow the air, the Pulse laser hit on the stainless steel plate, so that the cutting head from top to bottom movement, until the Blue Spark is the most focal point. This can calculate the focus, in the future cutting process according to different thickness of the plate to take the corresponding focusing.
(2) Oblique plate method: The vertical axis of the plastic plate with oblique angle to the horizontal pull, looking for the minimum point of the laser beam focus.
(3) Printing method: The cutting head from top to bottom movement, on the plastic plate laser beam printing, the minimum diameter of the printing focus.
(4) Parallel light tube. This is a commonly used method, that is, in the output end of the CO2 laser with a parallel light tube to expand the beam processing, the beam diameter widened, the divergence angle smaller, so that in the cutting work range of near-end and distal focus beam size near the same.
(5) The lower axis of an independent moving lens is added to the cutting head, and the z-axis of the distance (standoff) from the control nozzle to the material surface is two separate parts. When the machine tool worktable moves or the optical axis moves, the light beam moves from the near end to the distal F axis simultaneously, so that the spot diameter of the beam will be consistent in the whole machining area.