lézerrezonátorból
Lézerrezonátor, commonly referred to as a laser cavity, is a fundamental component of a laser that provides optical feedback, enabling stimulated emission to occur. It consists of a pair of mirrors positioned at either end of the laser medium. One mirror is typically highly reflective, while the other is partially reflective, allowing a portion of the generated light to escape as the laser beam. The mirrors are precisely aligned to ensure that light reflected back and forth within the cavity passes through the laser medium multiple times. This repeated passage amplifies the light through stimulated emission. The cavity also determines the wavelength and spatial distribution of the laser output. Different cavity configurations, such as stable and unstable resonators, are used to achieve specific laser properties. The resonant frequencies of the cavity are determined by its length and the properties of the mirrors. For oscillation to occur, the gain provided by the laser medium must exceed the losses within the cavity. These losses are primarily due to absorption and scattering within the medium and imperfections in the mirrors, as well as transmission through the output coupler. The design of the lézerrezonátor is crucial for determining the power, beam quality, and spectral characteristics of the laser.