Light-emitting optical fibers with controllable anomalous small-angle scattering

Glow was studied from a light guide with anomalous optical losses into small-angle scattering, provided by means of the specifically modified method of chemical vapor deposition in fabricating the optical fiber. The dependence of the optical loss coefficient at a wavelength of 650 nm on the drawing temperature of fiber with 10 mol. % GeO2 in the core was investigated experimentally. Based on this dependence, a theoretical analysis was carried out in order to determine the technological parameters for fabricating a fiber with uniform glow at a length of several hundred meters. A 400 m long fiber specimen was fabricated, emitting light at a wavelength of 650 nm with a constant glowing brightness estimated at 23 μW/m and produced by a laser source with a power of 10 mW. Such fibers are proposed to be used as emergency light pointers for tunnels, corridors, stairs, and other black-out objects.