Each focus tool ist pre-set to the focal length of the corresponding lense and is appropriately colour coded. The operator simply hangs the focus tool on the laser head, and then moves the working table manually until the surface of the workpiece to be engraved touches the focus tool. Now the right focus point is set. This focus mode is fast and flexible.
This method is especially useful when you work with a lot of different materials, if the material thickness is unknown or can not be measured and for cylindrical objects.