Abstract: An optical component according to an embodiment of the present invention is constructed of a plurality of MCFs each having the same core constellation structure and among the plurality of MCFs, a maximum deviation of a core pitch between neighboring cores and a maximum deviation of a spot size of a fundamental mode at an operating wavelength satisfy a specific relation, thereby suppressing structural variation so as to keep a splice loss not more than 1 dB.

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.

Abstract: An optical multiplexer/demultiplexer includes a first fiber unit having an MCF and a GRIN lens, a second fiber unit having an MCF and a GRIN lens, and an optical filter. The optical filter is disposed between the GRIN lens of the first fiber unit and the GRIN lens of the second fiber unit and makes transmitted light and reflected light emitted from a core of the MCFs incident on a core of the MCFs. A leading end of the MCF and one end of the GRIN lens are held in contact with each other in the first fiber unit, while a leading end of the MCF and one end of the GRIN lens are held in contact with each other in the second fiber unit.

Abstract: There is provided an optical connector module in which an adhesive is interposed between a lens and a distal surface of an optical fiber, wherein the module includes a transparent positioning device and an optical fiber fixed in the positioning device. The positioning device has a lens provided to an end surface, a concave insertion portion into which the optical fiber is inserted and which is disposed so that the bottom surface in contact with the distal surface of the optical fiber is positioned opposite the lens, and a debris receiving portion that extends from the bottom surface in a radial direction of the optical fiber and has a surface continuous with the bottom surface.

Abstract: The present invention provides an optical branching device and an optical communication system which are easy to connect with optical fibers. In the optical branching device, when light emitted from an optical fiber in a front stage is incident on an entrance port of a multicore optical fiber, the light propagates through a first core and then is distributed from the first core to four second cores by core-to-core crosstalk between the first and second cores. The light beams distributed to the four second cores propagate through the respective cores and are emitted to four optical waveguides optically coupled core-to-core thereto within a fan-out part at exit ports.

Abstract: An optical fiber connecting method and optical fiber connecting structure which can efficiently connect a multicore fiber to a plurality of single-core fibers with high accuracy. The method comprises preparing an MT ferrule for holding an MCF, axially rotating and positioning the MCF with respect to the MT ferrule, and then fixing the MCF to the MT ferrule; preparing an MT ferrule for holding a plurality of SCFs, positioning them such that cores are arranged at respective positions corresponding to arrangements of a plurality of cores in the MCF, and then fixing the plurality of SCFs to the MT ferrule; and positioning and joining the MT ferrules such that the plurality of cores face the respective single cores, so as to connect the MCF to the plurality of SCFs.

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: 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: There is provided an optical connector module in which an adhesive is interposed between a lens and a distal surface of an optical fiber, wherein the module includes a transparent positioning device and an optical fiber fixed in the positioning device. The positioning device has a lens provided to an end surface, a concave insertion portion into which the optical fiber is inserted and which is disposed so that the bottom surface in contact with the distal surface of the optical fiber is positioned opposite the lens, and a debris receiving portion that extends from the bottom surface in a radial direction of the optical fiber and has a surface continuous with the bottom surface.

Abstract: The present invention provides an optical branching device and an optical communication system which are easy to connect with optical fibers. In the optical branching device, when light emitted from an optical fiber in a front stage is incident on an entrance port of a multicore optical fiber, the light propagates through a first core and then is distributed from the first core to four second cores by core-to-core crosstalk between the first and second cores. The light beams distributed to the four second cores propagate through the respective cores and are emitted to four optical waveguides optically coupled core-to-core thereto within a fan-out part at exit ports.

Abstract: The present invention relates to an optical signal processor which can perform favorable optical signal processing even when there are environmental changes and the like. The optical signal processor inputs light emitted from an end face of an optical fiber, subjects the inputted light to processing according to its wavelength, and outputs the processed light so as to make it incident on the end face of the optical fiber; and comprises optical systems, a diffraction grating device, mirror reflectors, an optical path turning part, and a monitor part. The optical path turning part transmits therethrough a part of the incident light and reflects at least a part of the remnant. The optical system monitors the light transmitted through the optical path turning part.

Abstract: An optical signal processor, capable of eliminating design change of lens optical systems, it is fabricating by selecting one or more optical waveguides, each having a mode field diameter such that a desired band width of the transmission characteristics of the whole optical signal processor with respect to the light beam are selected as the input and output optical waveguides. When one optical waveguide is selected, the selected optical waveguide is applied as a common optical waveguide corresponding to both input and output optical waveguides. When two optical waveguides are selected, one is applied to the input optical waveguide and the other is applied to the output optical waveguide.

Abstract: To provide an optical signal processor which can perform favorable optical signal processing even when there are environmental changes and the like. An optical signal processor 1 inputs light emitted from an end face of an optical fiber 11, subjects the inputted light to processing according to its wavelength, and outputs the processed light so as to make it incident on the end face of the optical fiber 11; and comprises optical systems 111 to 113, a diffraction grating device 120, reflecting mirrors 131 to 133, an optical path turning part 140, and a monitor part 150. The optical path turning part 140 transmits therethrough a part of the incident light and reflects at least a part of the remnant. The optical system 113 monitors the light transmitted through the optical path turning part 140.

Abstract: The present invention is related to a method of fabricating an optical signal processor capable of eliminating design change of lens optical systems and so on. The optical signal processor includes input and output optical waveguides, and further includes a first lens optical system, a spatial wavelength-dividing element, a second lens optical system, and a spatial optical modulator, respectively arranged on an optical path between the input and output optical waveguides. For fabricating the optical signal processor, one or more optical waveguides each having a mode field diameter such that a desired band width of the transmission characteristics of the whole optical signal processor with respect to the light beam are selected as the input and output optical waveguides. When one optical waveguide is selected, the selected optical waveguide is applied as a common optical waveguide corresponding to both input and output optical waveguides.