Dispersion compensation fiber and dispersion compensation module

A dispersion compensating module, comprising:

• a winding spool,
• a dispersion compensating fiber wound onto the winding spool, the dispersion compensating fiber including:
• a central core region having an outer radius r1 of 1.5 μm to 2 μm, and a maximum refractive index Δ1 of 1.15% to 1.6%, and
• a cladding region comprising (i) a first inner cladding (trench) region, surrounding the central core, having a refractive index Δ2 of −0.3% to −0.45% and an outer radius r2 of greater than 5 μm and less than or equal to 7 μm, (ii) a second inner cladding (ring) region, surrounding the first inner cladding region, having a refractive index Δ3 of 0.35% to 0.5% and a radius r3 of 6 μm to 8 μm, and (iii) an outer cladding region, surrounding the second inner cladding region,
• wherein the DCF exhibits a cable cutoff of less than 1260 nm and a mode field diameter at 1310 nm of greater than 4 microns.

An optical transmission system, comprising:

• a transmitter
• a receiver;
• an optical fiber transmission link optically coupling the receiver and the transmitter;
• wherein the optical fiber transmission link comprises a length of single mode fiber and a dispersion compensating module coupled to the length of single mode fiber, wherein the dispersion compensating module comprises:
• a winding spool,
• a dispersion compensating fiber wound onto the winding spool, the dispersion compensating fiber comprising:
• a central core region having an outer radius r1 of 1.5 μm to 2 μm, and a maximum refractive index Δ1 of greater than or equal to 1.15% and less than 1.6%, and
• a cladding region comprising (i) a first inner cladding (trench) region, surrounding the central core, having a refractive index Δ2 of −0.3% to −0.45% and an outer radius r2 of greater than 5 μm and less than or equal to 7 μm, (ii) a second inner cladding (ring) region, surrounding the first inner cladding region, having a refractive index Δ3 of 0.35% to 0.5% and a radius r3 of 6 μm to 8 μm, and (iii) an outer cladding region, surrounding the second inner cladding region,
• wherein the DCF exhibits a cable cutoff of less than 1260 nm and a mode field diameter at 1310 nm of greater than 4 microns, and
• wherein the optical fiber transmission link comprising the dispersion compensating fiber coupled to the single-mode fiber and operating at wavelengths between 1265 nm and 1375 nm increases maximum link lengths of the optical fiber transmission link by more than 60% as compared to the link length of the optical fiber transmission link with the single-mode fiber only, and
• wherein the maximum link length is calculated from the maximum allowed positive and negative accumulated dispersion at wavelengths between 1265 nm and 1375 nm.