Nd:YAG stands for neodymium-doped yttrium aluminium garnet; Nd:Y3Al5O12. It is a crystal that is used as a lasing medium for solid-state lasers. The Nd:YAG laser at 1064 nm, can be frequency doubled to 532 nm green light.
Nd:YAG lasers are optically pumped using a flashlamp or laser diodes. They are one of the most common types of laser, and are used for many different applications.
Nd:YAG lasers typically emit light with a wavelength of 1064 nm, in the infrared. However, there are also transitions near 940, 1120, 1320, and 1440 nm. Nd:YAG lasers operate in both pulsed and continuous mode.
Pulsed Nd:YAG lasers are typically operated in the so called Q-switching mode: An optical switch is inserted in the laser cavity waiting for a maximum population inversion in the neodymium ions before it opens. Then the light wave can run through the cavity, depopulating the excited laser medium at maximum population inversion. In this Q-switched mode, output powers of 250 megawatts and pulse durations of 10 to 25 nanoseconds have been achieved. The high-intensity pulses may be efficiently frequency doubled to generate laser light at 532 nm, or higher harmonics at 355 and 266 nm.
- Cosmetic medicine
- Fluid dynamics
- Military range finders
In cosmetic applications, ND Yag 1064 lasers are used for laser hair removal and the treatment of minor vascular defects such as spider veins on the legs and face, treament of wrinkles and skin tightening.