Abstract:

After a historic, we get onto the principles of interactions between light and matter and the conditions that lead to light amplification. Then we treat the oscillator laser which is the association of a resonant cavity and a light amplifier area. Finally, we describe the devices behind the word « laser » : oscillators and amplifiers, solid lasers, liquid (colouring) or gaseous.

Keywords:

Stimulated emission, Lasers, Laser oscillators, Light amplifiers,