Patent ID: 6922514

Claim:
An optical transmission fiber with a low non-linearity coefficient γ and high effective area for use in a WDM optical transmission system, the optical transmission fiber comprising: a core region comprising: a glass inner core having a first maximum refractive index difference Δn 1 ; a first glass layer radially surrounding the inner core, having a refractive index difference Δn 2 less than Δn 1 ; and a second glass layer radially surrounding the first layer, having a second maximum refractive index difference Δn 3 greater than zero; and a low loss cladding surrounding the second glass layer, wherein the non-linearity coefficient γ is less than about 2 W −1 km −1 , the effective area is greater than 45 μm 2 , a total dispersion for the fiber in a wavelength range of 1530 nm to 1565 nm is about 5 to 10 ps/nm/km, and a dispersion slope for the fiber at a wavelength of 1550 nm is less than or equal to about 0.06 ps/nm 2 /km.