ABSTRACT
The group of self-contained lasers includes a large number of various gas lasers the common hallmark feature of which is the self-contained lasing (induced transitions) over time, due to the properties of the laser (working) levels, with the schematic representation shown in Fig. I.1. The upper (2) level is efficiently populated as a result of some process (for example, in collisions with electrons or excited molecules) and the lower level (1) is metastable and populated only by the spontaneous decay of the upper level by the laser (working) transition with A21 probability.
