A circuit board includes a substrate, a first inner circuit layer, a second inner circuit layer, a first insulating layer, a first optical fiber extending along a first direction, an optical component, an electrical component, a transparent insulating layer, a first inclined surface, a first reflective layer, a second inclined surface, a second reflective layer, and a second optical fiber extending along a second direction.

An optical waveguide is configured to guide an optical beam, and the optical waveguide includes a down-taper element configured to reduce a diameter of an incoming light beam having a random polarization; a dual-core directional coupler element configured to separate the incoming light beam into a horizontally-polarized beam and a vertically-polarized beam, each beam being confined in first and second cores, respectively; and a core fan-out element configured to increase a distance between the horizontally-polarized beam and the vertically-polarized beam upon exit from the core fan-out element. Each of the down-taper element, the dual-core directional coupler element, and the core fan-out element are 3-dimensional, 3D, printed using a single material.

A circuit board includes a substrate, a first inner circuit layer, a second inner circuit layer, a first insulating layer, a first optical fiber extending along a first direction, an optical component, an electrical component, a transparent insulating layer, a first inclined surface, a first reflective layer, a second inclined surface, a second reflective layer, and a second optical fiber extending along a second direction.

An optical fiber fixing tool includes: a fiber accommodating body having a fiber accommodating groove that accommodates: at least a part of an uncovered bare portion of an optical fiber and a boundary part between the uncovered bare portion and a covered portion of the optical fiber, a cover being removed to expose a bare fiber in the uncovered bare portion; and a fixing resin that fills an inside of the fiber accommodating groove and fixes at least the part of the uncovered bare portion and the boundary part. In a cross-sectional view of the fiber accommodating groove viewed from a cross section of the optical fiber, the entire uncovered bare portion and the entire boundary part are accommodated in the fiber accommodating groove, and the fixing resin covers an entire outer circumference of the uncovered bare portion and an entire outer circumference of the boundary part.

A multicore optical fiber that includes a plurality of waveguiding cores disposed in a cladding. The plurality of cores are situated adjacent to at least one other core with a core center to core center spacing being not larger than 10 times the radius of the average core, such that the greater than 10% of the light will couple from one core to the adjacent core over a propagating distance of 1 cm, along the fiber length so as to provide coupling between the adjacent cores and to enable quantum walk. The plurality waveguiding cores are disposed in the cladding in a ring distribution or at least a portion of the ring distribution.

A multicore optical fiber that includes a plurality of waveguiding cores disposed in a cladding. The plurality of waveguiding cores include one or more first waveguiding cores that have a first propagation constant and one or more second waveguiding cores that have a second propagation constant, where the first propagation constant differs from the second propagation constant. The one or more first waveguiding cores and the one or more second waveguiding cores are disposed in the cladding in a ring distribution and at least a portion of the ring distribution is arranged based on a quasi-periodic sequence having a plurality of sequence segments. Each sequence segment is determined based on a quasi-periodic function, has an order, and corresponds to an arrangement segment of a first waveguiding cores, a second waveguiding cores, or combinations thereof. The ring distribution includes at least one arrangement segment corresponding with a third-order sequence segment or higher of the quasi-periodic sequence.

Disclosed is an optical interconnection device that includes an alignment ferrule assembly formed from an alignment substrate and optical fibers. The optical interconnection device also has an alignment assembly formed by a planar support member with guide features. A receiving region resides between the guide features in which the alignment substrate is secured. An evanescent optical coupler can be formed using the optical interconnection device as a first device and another optical interconnection device as a second device. The second device is constituted by a planar lightwave circuit that operably supports waveguides and an adapter. The adapter of the second device is configured to engage the alignment assembly of the first device to place the optical fibers and the optical waveguides of the respective devices in evanescent optical communication.

A multicore optical fiber that includes a plurality of waveguiding cores disposed in a cladding. The plurality of cores are situated adjacent to at least one other core with a core center to core center spacing being not larger than 10 times the radius of the average core, such that the greater than 10% of the light will couple from one core to the adjacent core over a propagating distance of 1 cm, along the fiber length so as to provide coupling between the adjacent cores and to enable quantum walk. The plurality waveguiding cores are disposed in the cladding in a ring distribution or at least a portion of the ring distribution.

A multicore optical fiber that includes a plurality of waveguiding cores disposed in a cladding. The plurality of waveguiding cores include one or more first waveguiding cores that have a first propagation constant and one or more second waveguiding cores that have a second propagation constant, where the first propagation constant differs from the second propagation constant. The one or more first waveguiding cores and the one or more second waveguiding cores are disposed in the cladding in a ring distribution and at least a portion of the ring distribution is arranged based on a quasi-periodic sequence having a plurality of sequence segments. Each sequence segment is determined based on a quasi-periodic function, has an order, and corresponds to an arrangement segment of a first waveguiding cores, a second waveguiding cores, or combinations thereof. The ring distribution includes at least one arrangement segment corresponding with a third-order sequence segment or higher of the quasi-periodic sequence.

A photonic chip includes a connecting means, a substrate, and a waveguide layer. The photonic integrated waveguide and the optical fiber each have a front end portion. The connecting means includes a groove configured to receive the front end portion of the optical fiber. The groove is essentially U-shaped in its cross section, and the groove has a bottom surface and two inner side surfaces. A least one of both inner side surfaces of the U-shaped groove has a coating of an elastic material configured to hold in place the optical fiber after it is inserted into the groove. The invention further relates to an optical device which includes a photonic chip and an optical fiber, as well as a method or production of such a photonic chip.