Ruby laser weaknesses in the lining. Ruby lasers were used extensively in tattoo and hair removal, but are being replaced by alexandrite and s in this application. The ruby laser was the first laser to be made functional. Built by Theodore Maiman in 1960, the device was created out of the concept of an "optical maser," a maser that could operate in the visual or infrared regions of the spectrum. In 1958, after the inventor of the maser, Charles Townes, and his colleague, Arthur Schawlow, published an article in the "Physical Review" regarding the idea of optical masers, the race to build
Laser linewidth Laser linewidth Laser linewidth is the spectral linewidth of a laser beam. Two of the most distinctive characteristics of laser emission are spatial coherence and spectral coherence. While spatial coherence is related to the beam divergence of the laser, spectral coherence is evaluated by measuring the laser linewidth of the radiation. Although the concept of laser linewidth can have varied theoretical descriptions here, this article provides a simple experimental description. One of the first methods used to measure the coherence of a laser was interferometry. An alternative approach is the use of spectrometry. Laser linewidth in a typical single-transverse-mode He-Ne