Solid-state laser excitation methods
There are two excitation methods for laser welding: lamp excitation and semiconductor laser excitation.
Lamp excitation
A noble gas* is generally used in the light source for lamp excitation. As such, this method is also called the “noble gas flash lamp” or “flash lamp” excitation method. Compared with other light sources, lamps offer excellent cost performance. However, due to the wide emission spectrum, problems such as absorption spectrum compatibility with the laser medium and heat load on the laser medium.
Noble gas is a collective term for the six elements of helium, neon, argon, krypton, xenon, and radon, which make up Group 18 on the periodic table.
- A
- Mirror
- B
- Elliptical mirror
- C
- Flash lamp
- D
- Laser crystal
- E
- Oscillated beam
Semiconductor laser (LD: laser diode) excitation
Semiconductor laser (LD: laser diode) excitation features a narrow emission spectrum with excitation possible by selecting the specific absorption transition of the laser medium. This excitation method also offers high absorption efficiency and excellent beam convergence for high-density excitation. Also, the burden on the laser medium is small, allowing for high reliability.
- A
- LD
- B
- Excitation light
- C
- Lens
- D
- Laser crystal
- E
- Oscillated beam