Currently there are a great number of materials available for use in the optical components.

Mostly the laser is not used by itself but rather, it is combined with a number of accessories and used as part of larger system.

There are four essential or basic components of laser, may be listed as:Active medium, Excitation mechanism, Feedback mechanism, Output coupler.

He-Ne stands for Helium-Neon. The He-Ne laser active medium consists of two gases which do not interact form a molecule.

The first working laser was built in 1960 by Maiman, using a ruby crystal and so called the Ruby laser.

The gallium Arsenide laser is designed in such a way that a piece of N-type Gallium Arsenide material is taken and a layer

The semiconductor laser is very small in size and appearance. It is similar to a transistor and has the operation like LED but the output beam has the characteristics of laser light

The lasers having the solid material as an active medium is called the solid state lasers. Generally there are two classes of solid state lasers.

From design point of view we can say that output of all lasers is not constant. Different types of applications require different types of lasers.

The actual process that occurs during the production of a beam of laser light is known as lasing process.