| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a dispersion compensated fiber which is small in bending loss, large in RDS and small in residual dispersion after cumulative wavelength dispersion compensation over the entire range of the U-band, and to provide a composite optical fiber transmission line which uses the dispersion compensated fiber. <P>SOLUTION: The dispersion compensated fiber is provided with at least a center core 1, side cores 2, a ring core 3 and clads 4. In the fiber, radius r<SB>1</SB>is set to 1.2 to 2.0μm, radius r<SB>3</SB>is set to 6 to 8μm, r<SB>2</SB>/r<SB>1</SB>is set to 2.0 to 4.0,Δ1 is set to +1.3 to +2.0%,Δ2 is set to -1.3 to -0.6%,Δ3 is set to +0.1 to +0.5%, wavelength dispersion is set equal to or smaller than -20ps/nm/km at a wavelength selected from the U-band, RDS is set to 0.008 to 0.012nm<SP>-1</SP>, bending loss at a diameter of 20mm is made equal to or smaller than 40dB, and a cut-off wavelength is set shorter than 1.625μm under the operating condition. <P>COPYRIGHT: (C)2005,JPO&NCIPI</p> |
