1. There are two recognized principles for laser marking machine
(1).Thermal processing laser beam with high energy and density, irradiates the surface of the material, absorbs laser energy on the surface of the material and generates thermal excitation process in the irradiated area, thereby causing the surface temperature of the material to rise, resulting in metamorphosis, melting, ablation and evaporation.
(2).Cold processing photons with high-load energy, interrupts the chemical bonds in the material or the surrounding medium, causing the material to undergo non-thermal process destruction. This type of cold processing has particular significance in laser marking because it is not thermal ablated,it is cold stripping that interrupt the chemical bond,without side effects of heat damage,that interrupt the cold stripping of the chemical bonds.Therefore, the inner layer and the vicinity of the surface to be processed do not generate any heat or thermal deformation.
2.Common classification of laser marking machine
According to different lasers,can be divided into:
YAG laser marking machine,
Semiconductor laser marking machine,
Co2 laser marking machine,
Fiber laser marking machine.
According to the different visibility of the laser, can be divided into:
UV laser marking machine (invisible laser),
Green laser marking machine (visible laser),
Infrared laser marking machine (invisible laser)
(1).YAG laser marking machine: Using krypton lamp as the energy source, ND:YAG, as a medium for generating laser light,the excitation source emits incident light with a specific wavelength, which causes the material to be inverted in a real way, releases the laser beam through the energy level transition, amplifies and shapes the laser energy to form a usable laser beam.
(2)Semiconductor Laser Marking Machine：Using high-power semiconductor quantum laser instead of gas pump solid-state crystal as the gain medium, to produce a new wavelength laser, then use crystal second harmonic generation(SHG)and the third harmonic generation(THG) to produce different wavelengths laser. Semiconductor laser marking machine can be divided into side-pumped semiconductor laser marking machine and end-pumped laser marking machine, side-pumping means that the light source is mounted on the side of the laser rod, and the end-pump is the light source installed in the end of a laser rod.
(3)Co2 laser marking machine: CO2 gas filled into the discharge tube as a laser medium, when the electrode plus a high voltage, glow discharge is produced in the tube, gas molecules can be released to the laser, the laser energy is amplified to form laser beam for material processing .
(4)Fiber laser marking machine:Using glass fiber doped rare earth element as the gain medium, with the action of the pump light， form a high power density within the fiber easily, cause "bean of particles inversion"in the laser energy level of the laser work material , when appropriate add the positive and negative loop （resonant cavity）, can form a laser oscillation output.
3.Different wavelengths of laser marking machine
(1)UV laser marking machine： 255nm
(2)Green laser marking machine： 532nm
(3)YAG laser marking machine：1064nm
(4)Semiconductor laser marking Machine：1064nm
(5)fiber laser marking machine：1064nm
(6)CO2 laser marking machine：10.64um
4.Consumptive material/Wearing parts
YAG laser marking machine：laser krypton lamp, total reflection mirror, half reflection mirror, laser rod, galvanometer lens
Semiconductor laser marking machine: semiconductor laser (semiconductor module),total reflection mirror, half reflection mirror, laser rod, galvanometer lens
CO2laser marking machine：CO2 laser tube, reflex lens group, galvanometer lens
Fiber laser marking machine: no