Laser power density has a great influence on the cutting speed, so the selection of the focal position is particularly important. The spot size of the laser beam is proportional to the length of the lens. There are three simple ways to find the cutting focus position in the industrial files.
1.Pulse method: Let laser beam print on a plastic sheet,moving the laser head from top to bottom,checking all holes and the smallest diameter is the focus.
2.Slant plate method: Using a slant plate under the vertical axis, moving it horizontally and looking for the laser beam at the minimum focus.
3.Blue Spark: Remove the nozzle, blow the air, pulse on stainless steel plate, move the laser head from top to bottom, until find the blue spark as the focus.
At present, many manufacturers’ machines have automatic focus.Automatic focus can significantly improve the laser cutting machine’ efficiency, piercing time on thick plate is significantly reduced; The machine can adjust automatically to find the focus position based on different materials and thickness.