The generation of high-quality laser output from a multi-line laser relies on two main principles: first, lasers operating at multiple wavelengths interact within an optical coupler to form a single, high-quality laser beam; second, because the spectral linewidth of each individual wavelength component is extremely narrow, the resulting laser beam exhibits a very narrow spectrum, achieving a high degree of monochromaticity and coherence.
Analysis reveals that by utilizing the interaction of lasers at multiple wavelengths, multi-line lasers can significantly enhance beam quality; consequently, they are widely employed across various industrial and scientific research fields.