Patent ID: 6952516

Claim:
A low attenuation optical fiber for wavelength division multiplexing, comprising: a light transmitting region having a dispersion characteristic (D) of 5.0 or more in absolute value over a wavelength band of 1530 to 1565 nm; a dispersion slope (S) of 0.04 ps/nm 2 /km to 0.08 ps/nm 2 /km over the wavelength band of 1530 to 1565 nm; a polarization mode dispersion characteristic (PMD) of no more than 0.12 ps/√{square root over (k)}m at a wavelength of 1550 nm; an effective area (Aeff) of no more than 90 μm 2 at the wavelength of 1550 nm; a loss increase of no more than 15 dB/m at the wavelength of 1550 nm as coiled in a diameter of 20 mm, and a transmission loss at the wavelength of 1550 nm does not exceed 0.25 dB/km under standard atmospheric conditions, wherein said transmission loss at the wavelength of 1550 nm does not exceed 0.25 dB/km after being exposed, for a predetermined period, to an atmosphere consisting substantially of hydrogen under ordinary atmospheric pressure at ordinary temperature.