Laser cleaning is an effective method to remove dirt particles and films of different materials and sizes on solid surfaces. Laser cleaning is to form a laser beam with a specific spot shape and energy distribution after optical focusing and spot shaping of a continuous or pulsed laser with high brightness and good directionality. After the contaminant material absorbs the laser energy, it will produce a series of complex physical and chemical processes such as vibration, melting, burning, and even gasification, and finally make the contaminant detach from the surface of the material. Even if the laser acts on the cleaned surface, most All are reflected off, and will not cause damage to the substrate, so as to achieve the effect of cleaning.

• The pump source supplies the medium with energy. It stimulates the laser in a way that the electrons in the molecules are temporarily lifted to a higher energy state.
• The electrons in the stimulated state cannot remain there as they drop drastically to a lower energy level.
• They give off a photon as they lose the excess energy they get from the pump. It’s known as impromptu emission and the photons created by this process are the seed for the production of a laser.
• The photons are given off by the impromptu discharge. Lastly, they hit other electrons present in the elevated energy states. When an approaching photon “knocks” the electron from the stimulated state to a lower level of energy, another photon is formed. These photons are consistent. It implies that they’re in phase, has a similar wavelength, and are moving in the same direction. The procedure is referred to as stimulated emission.
• Photons are given off in every direction. Nonetheless, some of them move lengthwise to hit the vibrator mirrors, which bounce back via the medium. The vibrator mirrors determine the preferred amplification direction for the exciting discharge. There has to be a greater atoms percentage in the stimulated form than the lower energy levels for amplification to take place. This population inversion of excess atoms in the stimulated state causes several conditions needed for the generation of a laser.
• The laser’s concentration spot is directed towards the workpiece surface which you’re welding. The concentration of light energy transforms into heat (thermal) energy at the surface. The heat makes the material thaw. It advances via the surface through a procedure known as surface conductivity. The gleam level of energy stays below the evaporation temperature of the workpiece material. The perfect thickness of the materials you’re welding should be 20mm. The energy of the laser is concentrated. It’s a benefit if you’re working with materials with high thermal conductivity.