US 7,321,709 B2
Optical cable
Tomoyuki Yokokawa, Yokohama (Japan); and Eisuke Sasaoka, Yokohama (Japan)
Assigned to Sumitomo Electric Industries, Ltd., Osaka (Japan)
Appl. No. 10/578,711
PCT Filed Nov. 11, 2005, PCT No. PCT/JP2005/020707
§ 371(c)(1), (2), (4) Date May 10, 2006,
PCT Pub. No. WO2006/051898, PCT Pub. Date May 18, 2006.
Claims priority of application No. 2004-327950 (JP), filed on Nov. 11, 2004.
Prior Publication US 2007/0104429 A1, May 10, 2007
Int. Cl. G02B 6/44 (2006.01)
U.S. Cl. 385—103  [385/100; 385/102] 15 Claims
OG exemplary drawing
 
1. An optical cable, comprising:
a tension member;
a tube comprised of one of plastic and metal, stranded together around said tension member, and containing one or more coated optical fibers inside; and
an outer sheath covering an outer periphery of said tube,
wherein a ratio of A/B is 6.3 or more but 7.0 or less, where said each coated optical fiber has a mode field diameter A of 8.6±0.4 μm at a wavelength of 1.31 μm, and a fiber cutoff wavelength of said each coated optical fiber is B μm, and
wherein each of said coated optical fibers comprises a core region made of pure silica glass, and a cladding region made of F-doped silica glass.