Solid State Lasers

The Nd:YAG laser is a solid state laser where the medium is a rod of Yttrium-Aluminum-Garnet doped with Neodymium. This glass like rod is excited by diodes. The resulting laser light has a wavelength of 1.06um (infrared range); the beam can be transferred to the point of use through an optical fiber, making it very flexible. The transmission through glass, Nd:YAG laser's strategic advantage in terms of flexibility, is also its main disadvantage. For safety reasons, Nd:YAG lasers are required to be operated in fully enclosed work cells and need special protective equipment to be used by the operator.

In the Yt:YAG Disk laser the crystal has the shape of a narrow disk and is mounted on a heat exchanger for effective and even cooling. The surface of the heat exchanger also acts as a total reflector in the resonator setup. This design produces a laser radiation marked by a high beam quality.

The Fiber laser consist of laser diodes and a optical fiber, the core of which is enriched with a laser-active medium. This “laser core” is surrounded by the “pump coat”, into which the light of the laser diodes is radiated from one end. Multiple reflections on the outer edge of the pump coat causes the pump light to be sent through the laser core repeatedly where the active laser medium is stimulated and emits laser radiation.

The solid state nature of this laser eliminates the need for resonator gases; however, for assist gases the requirements are very similar to those of CO2 lasers.