Corning Incorporated
Low bend loss optical fiber with step index core

Abstract:

A single mode optical fiber, comprising: (i) a silica based core having a step refractive index profile with an alpha of greater than 10, a relative refractive index .DELTA..sub.1MAX, and an outer radius r.sub.1, wherein 6.25 microns>r.sub.1.gtoreq.4.75 microns, the core further comprising Cl, Ge, or a combination thereof; (ii) a first cladding region in contact with and surrounding the core, the first cladding region having a relative refractive index .DELTA..sub.2MIN, an inner radius r.sub.1, and an outer radius r.sub.2, wherein r.sub.2<20 microns; and (iii) an outer cladding region surrounding the first cladding region, the outer cladding region having a relative refractive index .DELTA..sub.3. The fiber<1300 nm, a 22m cable cutoff wavelength<1260 nm; and a bend loss<0.005 dB/turn when the optical fiber is bent around a 30 mm mandrel; <0.5 dB/turn when the fiber is bent around a 20 mm mandrel.