A beam combiner includes: a plurality of input optical fibers, a beam combination optical fiber and an output optical fiber; the input optical fiber includes an input fiber core and an optical fiber input cladding layer wrapping an outer wall of the input fiber core, the output optical fiber includes an output fiber core and an optical fiber output cladding layer wrapping an outer wall of the output fiber core, a cross section of the optical fiber input cladding layer is fan-shaped or hexagonal and is provided with a groove and/or a protrusion along an axial direction, the plurality of input optical fibers are nested with each other to form the beam combination optical fiber, fiber cores in the beam combination optical fiber are all connected to the output fiber core, and a beam combination cladding layer of the beam combination optical fiber is connected to the output fiber core.

The present disclosure relates to semiconductor structures and, more particularly, to waveguide attenuators and methods of manufacture. The structure includes: a main bus waveguide structure; a first hybrid waveguide structure evanescently coupled to the main bus waveguide structure and comprising a first geometry of material; and a second hybrid waveguide structure evanescently coupled to the main bus waveguide structure and comprising a second geometry of the material.

An object of the present disclosure is to provide an optical coupling device capable of controlling a coupling rate of optical coupling between two coupling optical fibers.

An optical coupling device of the present disclosure includes two coupling optical fibers each including a core and a clad and, between the two coupling optical fibers, a thickness variable member having a thickness between the two coupling optical fibers that varies by irradiation with light.

An object of the present disclosure is to enable an optical signal propagating through a core of an optical fiber to enter and exit without bending the optical fiber.

The optical fiber of the present disclosure includes: a core; a cladding layer having a refractive index lower than a refractive index of the core; and a coating layer that coats an outer periphery of the cladding layer, in which the cladding layer includes: a first cladding portion of which main component is the same as that of the core; and a second cladding portion of which main component is different from the main component of the first cladding portion, and is softer than the first cladding portion, and an interface between the first cladding portion and the second cladding portion is in contact with the core.

Embodiments herein describe a waveguide crossing that permits at least two optical signals to cross in two different directions. For example, one optical signal can propagate from left to right through the center of the waveguide crossing at the same time a second optical signal propagates up and down through the center of the crossing. In one embodiment, a circular disc is disposed at the center of the waveguide crossing through which the two (or more) optical signals pass. The shape of the circular disc can provide low insertion loss as the respective optical signals propagate between respective pairs of waveguides, as well as minimize cross talk between the two optical signals.

An object of the present disclosure is to provide an optical coupling device capable of controlling a coupling index of optical coupling between two optical fibers for coupling. An optical coupling device of the present disclosure includes two optical fibers for coupling having a core and a clad, and a refractive index variable member to change the refractive index by irradiation with light between the two optical fibers for coupling.

A manufacturing method of an optical splitter of the present disclosure includes: performing first processing that involves mounting a coated optical fiber on a jig configured to store the coated optical fiber, and polishing the coated optical fiber together with the jig until reaching a vicinity of a core of the coated optical fiber or the core of the coated optical fiber; performing second processing that involves applying a refractive index matching material having a refractive index lower than a refractive index of the core of the coated optical fiber onto a polished face of the coated optical fiber on the jig polished in the first processing or onto a polished face of an optical waveguide circuit having been polished in advance until reaching a vicinity of a core or reaching the core, and then bonding the polished faces to each other; and performing third processing that involves positionally aligning the polished faces bonded with each other in the second processing to move the jig or the optical waveguide circuit to a position at which a desired splitting ratio is obtained.

Embodiments herein describe a waveguide crossing that permits at least two optical signals to cross in two different directions. For example, one optical signal can propagate from left to right through the center of the waveguide crossing at the same time a second optical signal propagates up and down through the center of the crossing. In one embodiment, a circular disc is disposed at the center of the waveguide crossing through which the two (or more) optical signals pass. The shape of the circular disc can provide low insertion loss as the respective optical signals propagate between respective pairs of waveguides, as well as minimize cross talk between the two optical signals.

An optical coupler includes a first waveguide including a first multi-mode waveguide section having a cross-section characterized by a first height and a first width that is greater than the first height and a second waveguide including a second multi-mode waveguide section having a cross-section characterized by a second height and a second width that is greater than the second height. The first multi-mode waveguide section is positioned adjacent to the second multi-mode waveguide section at least partially above or below the second multi-mode waveguide so that light entering the first multi-mode waveguide section is coupled from the first multi-mode waveguide section to the second multi-mode waveguide section. Methods for coupling light between waveguides with the optical coupler and optical devices that include the optical coupler are also described.

A delivery fiber assembly suitable for delivering broad band light and including a delivery fiber and a connector member. The delivery fiber has a length, an input end for launching light, and a delivery end. The delivery fiber includes along its length a core region and a cladding region surrounding the core region, the cladding region includes a cladding background material having a refractive index N.sub.bg and a plurality of microstructures in the form of inclusions of solid material having refractive index up to N.sub.inc and extending in the length of the longitudinal axis of the delivery fiber, wherein N.sub.inc<N.sub.bg. The plurality of inclusions in the cladding region is arranged in a cross-sectional pattern including at least two rings of inclusions surrounding the core region. The connector member is mounted to the delivery fiber at a delivery end section of the delivery fiber including the delivery end.