Editing Single-mode optical fiber (section)

==History==
In 1961, [[Elias Snitzer]] while working at American Optical published a comprehensive theoretical description of single mode fibers in the [[Journal of the Optical Society of America]].<ref>{{Cite web|url=https://www.osa.org/en-us/about_osa/newsroom/obituaries/2012/elias_snitzer/|title=Elias Snitzer &#124; In Memoriam &#124; The Optical Society}}</ref><ref>{{Cite web|url=https://www.m2optics.com/blog/history-of-optical-fiber|title=History of Optical Fiber|first=Tiffany San|last=Souci|website=www.m2optics.com}}</ref>

At the Corning Glass Works (now [[Corning Inc.]]), Robert Maurer, Donald Keck and Peter Schultz started with fused silica, a material that can be made extremely pure, but has a high melting point and a low refractive index. They made cylindrical preforms by depositing purified materials from the vapor phase, adding carefully controlled levels of dopants to make the refractive index of the core slightly higher than that of the cladding, without raising attenuation dramatically. In September 1970, they announced they had made single-mode fibers with attenuation at the 633-nanometer helium-neon line below 20&nbsp;dB/km.<ref>{{Cite web|url=https://www.jeffhecht.com/history.html|title=Fiber Optic History &#124; Jeff Hecht|website=www.jeffhecht.com}}</ref>