Multi-core fiber and method of positioning of core of multi-core fiber

摘要

A multi-core fiber for accommodating multiple single mode cores in one optical fiber is provided with multiple types of non-identical cores having different propagation constants. Each of the multiple types of non-identical cores includes a core part and a cladding part covering an outer periphery of the core part. The cladding part has a double cladding structure including a first cladding for surrounding an outer periphery of the core part and a second cladding on the outer side of the first cladding. In the multiple types of non-identical cores, an optical electromagnetic profile in the core part and the first cladding is confined within a range of the core part and the first cladding, restricting a leakage thereof to the second cladding, and the propagation constant of each non-identical core is made different using the refractive index of the first cladding as a parameter.

主权项

1. A multi-core fiber for accommodating multiple single mode cores in one optical fiber,
the multiple cores comprising multiple types of non-identical cores having different propagation constants, each of the multiple types of non-identical cores comprising a core part and a cladding part that covers an outer periphery of the core part, and the cladding part of the non-identical cores comprising a double cladding structure including a first cladding for surrounding an outer periphery of the core part and a second cladding on the outer side of the first cladding, wherein, in the multiple types of non-identical cores, a propagation constant of a fundamental mode propagating through the core part is different in each of the non-identical cores, in the core part and the first cladding, an optical electromagnetic profile is confined within a range of the core part and the first cladding, both of which restrict a leakage of the optical electromagnetic profile to the second cladding, thereby rendering propagation characteristics of all core part uniform, and a refractive index of the first cladding is used as a variable so that the non-identical cores vary in the propagation constant of the fundamental mode propagating through the core part, thereby rendering the propagation constant being different in the multiple types of non-identical cores.