Patent ID: 7505657

Claim:
A single-mode optical fiber, having a prescribed mode field diameter MFD 1 (μm) at a first wavelength λ 1 , wherein a bending loss when measured at a second wavelength λ 2 (μm) and wound with a bending radius r (mm) is L b (dB) for one bending, the number of bendings is t b , a connector/splice loss with an optical fiber that has a prescribed mode field diameter MFD 2 (μm) at the first wavelength λ 1 is L s (dB) for one connection/splice point at the second wavelength λ 2 (μm), the number of connector/splice points is n s , and a mode field diameter dependence of a total loss coefficient L calculated by a formula (4) has a local minimal value in a range of MFD 1 ±0.5 μm, with the formula (4) being as follows: L=n s ·L s +t b ·L b (4) where n s >0, t b >0.