Spectral Characteristics of Laser Emission

The frequency spectrum of a laser is determined by the spectral range of the active laser medium, i.e., its gain profile, and by the resonator modes falling 

In this section we shall briefly discuss spectral characteristics of multimode laser emission and the effects that influence it. 

The frequency spectrum of a laser is determined by the spectral range of the active laser medium, i.e., its gain profile, and by the resonator modes falling within this spectral gain profile (Fig. 5.20). All resonator modes for which the gain exceeds the losses can participate in the laser oscillation. The active medium has two effects on the frequency distribution of the laser emission  

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