The Fiber Optics Illustrated Dictionary - Part 44 fills a gap in the literature by providing instructors, hobbyists, and top-level engineers with an accessible, current reference. From the author of the best-selling Telecommunications Illustrated Dictionary, this comprehensive reference includes fundamental physics, basic technical information for fiber splicing, installation, maintenance, and repair, and follow-up information for communications and other professionals using fiber optic components. Well-balanced, well-researched, and extensively cross-referenced, it also includes hundreds of photographs, charts, and diagrams that clarify the more complex ideas and put simpler ideas into their applications context | Fiber Optics Illustrated Dictionary A grazing-incidence grating may be used in a monochromator. A grazing incidence grating can be combined with a coated laser diode laser cavity and tuning component to provide sufficient signal dispersion for telecommunications frequency single-mode operation provided the cavity length is balanced to the wavelength. See Littman-Metcalf configuration. Contrast with Littrow configuration. great circle In geometry an imaginary circle on the surface of a sphere that is defined as the intersection of the surface and a plane passing through the center of that sphere. See Great Circle. Great Circle The name given to routes based upon Earth s spherical geometry the Great Circle is a navigational concept to describe the shortest distance over the Earth s surface assuming it was flat between two specified points. Airlines use Great Circle routes to minimize travel distances especially over long distances. The polar aircraft route from Vancouver BC on the west coast of North America which passes over Greenland and Iceland to London or Amsterdam is roughly a Great Circle route. Great Circle geometry is also of interest to radio operators sending and receiving signals that are propagated through the Earth s ionosphere. See grayline great circle. Great Eastern A massive six-masted coal-powered paddlewheeler constructed in London between 1854 and 1858. The ship measured almost 700 feet in length and 120 feet in breadth. It was originally a passenger ship but was not financially successful in this role. Later it was purchased at auction by Daniel Gooch and his colleagues Cyrus W. Field and Brassey and outfitted for laying cable a role that better suited the vessel. Large cable tanks were installed for storing and spooling the communications cable. In July 1865 the ship was used in an unsuccessful attempt to lay the transatlantic cable. A year later the ship left Ireland with almost 3 000 nautical miles of cable in her hold spooling more than half
