Abstract: An MCF of the present embodiment has eight or more cores. A diameter of a common cladding is not more than 126 ?m. Optical characteristics of each core are as follows: a TL at a predetermined wavelength of 1310 nm is not more than 0.4 dB/km; an MFD at the predetermined wavelength is from 8.0 ?m to 10.1 ?m; a BL in a BR of not less than 5 mm or in the BR of not less than 3 mm and, less than 5 mm is not more than 0.25 dB/turn at the predetermined wavelength; ?0 is from 1300 nm to 1324 nm; ?cc is not more than 1260 nm; an XT or XTs at the predetermined wavelength is not more than 0.001/km.

Abstract: An embodiment relates to a method for manufacturing an optical module having an MCF and two connection components, and enables rotational alignment of the MCF to be implemented with high accuracy even in short-haul optical wiring. The MCF is arranged in a region between the two connection components while an end thereof projects from one connection component. As this arrangement state is maintained, array positions of cores in the projecting end are observed from a side face and the MCF is rotationally aligned by a rotation grasp jig grasping the projecting end to adjust the array positions of the cores, based on the observation result.

Abstract: An MCF of the present embodiment has eight or more cores. A diameter of a common cladding is not more than 126 ?m. Optical characteristics of each core are as follows: a TL at a predetermined wavelength of 1310 nm is not more than 0.4 dB/km; an MFD at the predetermined wavelength is from 8.0 ?m to 10.1 ?m; a BL in a BR of not less than 5 mm or in the BR of not less than 3 mm and, less than 5 mm is not more than 0.25 dB/turn at the predetermined wavelength; ?0 is from 1300 nm to 1324 nm; ?cc is not more than 1260 nm; an XT or XTs at the predetermined wavelength is not more than 0.001/km.

Abstract: The present invention relates to an MCF and others with a structure for accurately aligning each of core arrangement directions of one or more MCFs to be fixed in a connector. Each of the MCFs has a marker as an index for rotational position. The ends of the MCFs are rotated while monitoring positions of the respective markers with a CCD camera or the like, whereby each of the core arrangement directions is aligned with a specific direction.

Abstract: A receptacle connector includes a receptacle ferrule, a receptacle housing and a spacer. The receptacle ferrule has a first front end portion having a receptacle interface part In the receptacle housing, the receptacle ferrule and a plug connector having a second front end portion having a plug interface part configured to be optically coupled with the receptacle interface part are to be accommodated. The spacer has a first surface configured to contact the first front end portion, and a second surface configured to contact the second front end portion. The spacer is arranged in the receptacle housing. At a state where the first front end portion is contacted to the first surface of the spacer and the second front end portion is contacted to the second surface of the spacer, the receptacle interface part and the plug interface part face each other at a predetermined interval.

Abstract: An adapter includes an optical connector accommodation part having a first cavity in which a first optical connector having a first front end portion is to be accommodated, and a second cavity in which a second optical connector having a second front end portion is to be accommodated, and a spacer having a first surface configured to contact the first front end portion, a second surface configured to contact the second front end portion, and a light transmission part configured to enable a light beam to pass therethrough. The spacer being arranged between the first cavity and the second cavity. At a state where the first front end portion is contacted to the first surface and the second front end portion is contacted to the second surface, the first optical interface part and the second optical interface part face each other at a predetermined interval.

Abstract: An optical coupling member includes an adapter and an optical connector. The optical connector has a ferrule, a connector housing, and a holding member. The holding member allows relative movement between the connector housing and the ferrule, and holds a relative angle around a central axis between the connector housing and the ferrule. The connector housing has a contact portion including a contact surface. The adapter has a sleeve and an adapter housing. The ferrule is inserted into the sleeve while the contact surface contacts with the adapter housing for elastically deforming the contact portion.

Abstract: A GRIN lens array of an embodiment has a structure for enabling a coupling face in which lens end faces of GRIN lenses are arranged, to be accurately polished so as to have a desired angle relative to optical axes of the GRIN lenses. The GRIN lens array has the GRIN lenses and a main body portion. The main body portion comprises a holding portion having a coupling face, and an edge portion having a reference face to be used as a reference in polishing of the coupling face. The respective thicknesses of the holding portion and the edge portion along the longitudinal direction of the GRIN lenses are set so as to form a step between the coupling face and the reference face.

Abstract: The present invention relates to an optical interconnection component enabling implementation of optical fiber connection with higher accuracy than by the conventional technologies. The optical interconnection component is configured to maintain arrangement of end faces of a plurality of rotationally-aligned MCFs, so as to reduce connection loss to another component. Since arrangement of the MCFs can be confirmed by markers provided on a holding portion holding the plurality of MCFs inside, it becomes feasible to achieve the optical connection with higher accuracy.

Abstract: The present invention relates to an MCF and others with a structure for accurately aligning each of core arrangement directions of one or more MCFs to be fixed in a connector. Each of the MCFs has a marker as an index for rotational position. The ends of the MCFs are rotated while monitoring positions of the respective markers with a CCD camera or the like, whereby each of the core arrangement directions is aligned with a specific direction.

Abstract: An embodiment relates to a method for manufacturing an optical module having an MCF and two connection components, and enables rotational alignment of the MCF to be implemented with high accuracy even in short-haul optical wiring. The MCF is arranged in a region between the two connection components while an end thereof projects from one connection component. As this arrangement state is maintained, array positions of cores in the projecting end are observed from a side face and the MCF is rotationally aligned by a rotation grasp jig grasping the projecting end to adjust the array positions of the cores, based on the observation result.

Abstract: An MCF of the present embodiment has eight or more cores. A diameter of a common cladding is not more than 126 ?m. Optical characteristics of each core are as follows: a TL at a predetermined wavelength of 1310 nm is not more than 0.4 dB/km; an MFD at the predetermined wavelength is from 8.0 ?m to 10.1 ?m; a BL in a BR of not less than 5 mm or in the BR of not less than 3 mm and, less than 5 mm is not more than 0.25 dB/turn at the predetermined wavelength; ?0 is from 1300 nm to 1324 nm; ?cc is not more than 1260 nm; an XT or XTs at the predetermined wavelength is not more than 0.001/km.

Abstract: According to the present invention, as a result of using a depressed or trench-assisted light-receiving waveguide in which the core is surrounded by a layer having a refractive index lower than that of a cladding as light-receiving means for receiving light outputted from a multi-core optical fiber, the layer of a low refractive index can inhibit the propagation of noise, etc. from the cladding to the core. Consequently, even in cases where the inter-core crosstalk is small, it is possible to accurately measure the inter-core crosstalk since components different from crosstalk-derived components in optical power are reduced.

Abstract: A receptacle connector includes a receptacle ferrule, a receptacle housing and a spacer. The receptacle ferrule has a first front end portion having a receptacle interface part In the receptacle housing, the receptacle ferrule and a plug connector having a second front end portion having a plug interface part configured to be optically coupled with the receptacle interface part are to be accommodated. The spacer has a first surface configured to contact the first front end portion, and a second surface configured to contact the second front end portion. The spacer is arranged in the receptacle housing. At a state where the first front end portion is contacted to the first surface of the spacer and the second front end portion is contacted to the second surface of the spacer, the receptacle interface part and the plug interface part face each other at a predetermined interval.

Abstract: An adapter includes an optical connector accommodation part having a first cavity in which a first optical connector having a first front end portion is to be accommodated, and a second cavity in which a second optical connector having a second front end portion is to be accommodated, and a spacer having a first surface configured to contact the first front end portion, a second surface configured to contact the second front end portion, and a light transmission part configured to enable a light beam to pass therethrough. The spacer being arranged between the first cavity and the second cavity. At a state where the first front end portion is contacted to the first surface and the second front end portion is contacted to the second surface, the first optical interface part and the second optical interface part face each other at a predetermined interval.

Abstract: A GRIN lens array of an embodiment has a structure for enabling a coupling face in which lens end faces of GRIN lenses are arranged, to be accurately polished so as to have a desired angle relative to optical axes of the GRIN lenses. The GRIN lens array has the GRIN lenses and a main body portion. The main body portion comprises a holding portion having a coupling face, and an edge portion having a reference face to be used as a reference in polishing of the coupling face. The respective thicknesses of the holding portion and the edge portion along the longitudinal direction of the GRIN lenses are set so as to form a step between the coupling face and the reference face.

Abstract: An optical coupling member includes an adapter and an optical connector. The optical connector has a ferrule, a connector housing, and a holding member. The holding member allows relative movement between the connector housing and the ferrule, and holds a relative angle around a central axis between the connector housing and the ferrule. The connector housing has a contact portion including a contact surface. The adapter has a sleeve and an adapter housing. The ferrule is inserted into the sleeve while the contact surface contacts with the adapter housing for elastically deforming the contact portion.

Abstract: The object of this invention is to provide an optical connector module 1 in which the possibility of scraped wastes to exist between the lens and the tip face of the optical fiber is less and which has high optical coupling efficiency. The optical connector module 1 comprises: an optical fiber 2 having a core 2a and a plastic cladding 2b made of a first resin; a positioning device 3 made of a second resin and including a fixing portion 4 in which the optical fiber 2 is inserted; and a lens 5, wherein the hardness of the second resin is higher than that of the first resin. The tip face 2ac of a glass core 2a may protrude from the tip face 2bc of the cladding 2b toward the bottom face 4c, or otherwise the tip face 2bc of the cladding 2b may protrude from the tip face 2ac of the glass core 2a toward the bottom face 4c.

Abstract: According to the present invention, as a result of using a depressed or trench-assisted light-receiving waveguide in which the core is surrounded by a layer having a refractive index lower than that of a cladding as light-receiving means for receiving light outputted from a multi-core optical fiber, the layer of a low refractive index can inhibit the propagation of noise, etc. from the cladding to the core. Consequently, even in cases where the inter-core crosstalk is small, it is possible to accurately measure the inter-core crosstalk since components different from crosstalk-derived components in optical power are reduced.

Abstract: An optical fiber cable is provided as one capable of preventing damage of an inside tube and an outside tube. An optical fiber cable 1 is provided with an optical fiber 2 for propagating laser light, an inside tube 3 housing an end portion of this optical fiber 2, and an outside tube 4 arranged outside the inside tube 3 and surrounding the inside tube 3. A space portion 5 is provided between the optical fiber 2 and an inner peripheral surface of the inside tube 3.