 Laser linewidth

Laser linewidth refers to the spectral width or range of wavelengths emitted by a laser light source. It's typically measured in terms of frequency (hertz) or wavelength (nanometers), and it quantifies the coherence of the laser light. A narrower linewidth indicates that the laser emits light over a very limited range of wavelengths, which corresponds to a highly coherent beam. The coherence is essential for various applications, including precision measurement, telecommunications, and interferometry.