A CO2 laser (carbon dioxide laser) generates an invisible light beam, which is created by a module that is filled with carbon dioxide. The laser bean has a wavelength of 10,600 nanometers (nm). The created thermal radiation is almost completely absorbed by the material being worked.
As a template for a CO2 laser engraving, any image or vector data can be used. With a special software it is converted into a CAD format, similar to a black and white bitmap, the file is then used to condinate the machine.
Rigid mirrors deflect the laser pulses which are typically used in glass processing, in a galvanometer scanner, where two movable mirrors tranfer the beam in accordance with the existing data in the X and Y directions. About 190 mm before the glass, the beam is focused directly onto the glass surface.
Due to the brittleness of the material, the energy density of about four nanoseconds laser pulse makes defined pieces flake off from the surface of the glass and so creates tiny damages, visible as white spots in diameter of about 0.15 mm.
The result of this processing is similar to a sand-blasted surface, but with a significantly smoother surface structure.