摘要 |
This multimode optical fiber comprises, from the center to the periphery, an inner core, an inner cladding, a depressed trench and an outer cladding, wherein the inner core has a radius r 1 comprised between 22 µm and 28 µm and a graded-index profile with a relative refractive index percent ” = n 0 2 - n cl 2 2 �¢ n 0 2 > 0.8%, where n 0 is the maximum index value of the inner core and n c1 is the minimum index value of the inner core; the inner cladding has a radius r 2 and a refractive index difference ”n 2 with respect to the outer cladding; the depressed trench has a radius r 3 and a negative refractive index difference ”n 3 with respect to the outer cladding and surrounds the inner cladding, wherein 0.0115807 + 0.0127543 × (r 2 - r 1 ) + 0.00241674 × 1000”n 3 - 0.00124086 × (r 3 - r 2 ) × 1000”n 3 < 4% and wherein ˆ« r 2 r 3 1000 �¢ ”n 3 r �¢ dr is less than -20 µm. |