US 12,181,707 B2 · Multi-core optical fiber and design method

Abstract

The present invention is to provide a multi-core optical fiber that can expand its transmission wavelength band, and extend its transmission distance by reducing crosstalk, and also provide a method for designing the multi-core optical fiber. A multi-core optical fiber according to the present invention includes: four cores that are arranged in a square lattice pattern in a longitudinal direction; and a cladding region that is formed around the outer peripheral portions of the cores and has a lower refractive index than the cores, the absolute value of the relative refractive index difference between the cores and the cladding region being represented by A. In the multi-core optical fiber, the diameter of the cladding region is 125+1 μm, the cutoff wavelength is 1.45 μm or shorter, the mode field diameter MFD at a wavelength of 1.55 μm is 9.5 to 10.0 μm, the bending loss at a wavelength of 1.625 μm and with a bending radius of 30 mm is 0.1 dB/100 turns or smaller, and the inter-core crosstalk at the wavelength of 1.625 μm is −47 dB/km or smaller.

Claims7

Dependent claims

A multi-core optical fiber comprising:

four cores that are arranged in a square lattice pattern in a longitudinal direction;
and
a cladding region that is formed around outer peripheral portions of the cores and has a lower refractive index than the cores, an absolute value of a relative refractive index difference between the cores and the cladding region being represented by A,
wherein
a diameter of the cladding region is 125±1 μm,
a cutoff wavelength is less than or equal to 1.45 μm,
a mode field diameter MFD at a wavelength of 1.55 μm is 9.5 to 10.0 μm,
a bending loss at a wavelength of 1.625 μm and with a bending radius of 30 mm is less than or equal to 0.1 dB/100 turns, and
inter-core crosstalk at the wavelength of 1.625 μm is less than or equal to −47 dB/km.

6 more elements

A multi-core optical fiber comprising:

four cores that are arranged in a square lattice pattern in a longitudinal direction;
first cladding regions that surround the respective cores;
and
a second cladding region that surrounds all of the four first cladding regions,
wherein
a refractive index is the highest in the cores, is the second highest in the second cladding region, and is the lowest in the first cladding regions, a relative refractive index difference between the cores and the first cladding regions is less than or equal to 0.8%, a ratio between a diameter of the cores and a diameter of the first cladding regions is within a range of 2.0 to 3.0,
a diameter of a cladding region including the first cladding regions and the second cladding region is 125±1 μm,
a cutoff wavelength is less than or equal to 1.45 μm,
a mode field diameter MFD at a wavelength of 1.55 μm is 9.5 to 11.4 μm,
a bending loss at a wavelength of 1.625 μm and with a bending radius of 30 mm is less than or equal to 0.1 dB/100 turns, and
inter-core crosstalk at the wavelength of 1.625 μm is less than or equal to −54 dB/km.

8 more elements

Dependencies are inferred from the claim text.

Multi-core optical fiber and design method

Life of this patent

Multi-core optical fiber and design method

Life of this patent

Abstract

Claims7