Laser welding
High-energy beam welding: electron beam and laser

The tool used in this process is a powerful laser beam generated in a cavity containing an active amplifying medium and propagating through the atmosphere or a guide to a focusing optic for use.

The wave is characterized by its power and frequency. The latter is determined by the energy of the photons emitted by the atoms or molecules of the active medium.

Note: a photon, without mass or electric charge, is not a particle but a quantity of energy with the expression :