Patent ID: 7970247
Filing Date: 2011-06-28
Classification: G02B

Abstract:
1. An optical-fiber buffer tube, comprising: a polymeric tube; and a plurality of optical fibers positioned within said polymeric tube, said optical fibers (i) complying with the ITU-T G.652.D recommendation but (ii) complying with neither the ITU-T G.657.A recommendation nor the ITU-T G.657.B recommendation; wherein said optical fibers, at a wavelength of 1550 nanometers, have a microbending sensitivity of more than 4.0 (dB/km)/(gf/mm) when measured by an expandable drum apparatus at a temperature between about −30° C. and 60° C.; wherein said optical-fiber buffer tube possesses a buffer-tube filling coefficient of between about 0.2 and 0.6; and wherein, upon subjecting said optical-fiber buffer tube to the mid-span testing according to the USDA Rural Electrification Administration mid-span standard, (i) each of said optical fibers enclosed within said buffer tube has increased attenuation of no more than about 0.1 dB and (ii) said optical fibers enclosed within said buffer tube have a mean increased attenuation of no more than about 0.05 dB.