Patent ID: 6282354
Filing Date: 2001-08-28
Classification: G02B

Abstract:
A single mode optical waveguide fiber optimized to have low attenuation comprising:a core glass region having a refractive index profile;an annular clad glass layer surrounding and in contact with the core glass region, the clad glass layer having a refractive index profile, wherein at least a portion of the core index profile is greater than at least a portion of the clad layer index profile; wherein, said core region includes,a center segment having an outer radius r.sub.1, a relative index .DELTA..sub.1 %, and a centerline having a relative index,a first annular segment, surrounding and in contact with the center segment, having a relative index .DELTA..sub.2 %, and,a second annular segment, surrounding and in contact with the first annular segment, having a center radius r.sub.3, a relative index .DELTA..sub.3 %, and a width w.sub.3 ;wherein,.DELTA..sub.1 %>.DELTA..sub.3 %.gtoreq..DELTA..sub.2 %.gtoreq.0; and.DELTA..sub.1 % is in the range 0.77% to 1.30%, r.sub.1 is in the range 2.04 .mu.m to 3.41 .mu.m, .DELTA..sub.2 % is in the range 0 to 0.16%, .DELTA..sub.3 % is in the range 0 to 0.51%, r.sub.3 is in the range 5.53 .mu.m to 10.21 .mu.m, and w.sub.3 is in the range 0 to 5.76 .mu.m.