Abstract: A multi-core optical fiber preform includes: a rod-shaped main cladding body having one or more main inner holes; main core rods inserted into the one or more main inner holes; and a tip continuously-installed portion disposed at one end of the rod-shaped main cladding body and including a glass rod having no core rod or having one core rod.

Abstract: A light diffraction element unit includes an optically-transparent substrate; a light diffraction element disposed on a main surface of the optically-transparent substrate; and a three-dimensional alignment mark disposed on the main surface in a vicinity of the light diffraction element and having a thickness greater than a thickness of the light diffraction element.

Abstract: 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.

Abstract: An imaging module of the invention includes an image-sensing device that has a light-receiving face, a substrate, a signal cable including a conductor, and a resin mold. A wiring of the substrate includes an electrode terminal and a cable terminal. The image-sensing device electrode is electrically connected to the electrode terminal via solder. The conductor is electrically connected to the cable terminal via solder. The resin mold coats the electrode surface, the cable terminal, the conductor, and the solder. On a plane of projection of the image-sensing device when viewed in a direction from the image-sensing device to the signal cable, the substrate, the resin mold, and the signal cable are disposed inside an outline of the image-sensing device.

Abstract: An optical receptacle includes: a first optical fiber; a second optical fiber connected to the first optical fiber by fusion splice; a ferrule including a fiber hole that holds an end of the first optical fiber; and a housing portion that houses therein: the ferrule, the first optical fiber, and a first portion of the second optical fiber. A fusion splice portion between the first optical fiber and the second optical fiber is disposed outside of the ferrule and within the housing portion.

Abstract: A heat pipe includes a flat container having an internal space in which a working fluid is sealed and a flat surface facing the internal space, and a wick disposed in the internal space. The wick includes a first wick having a plurality of first voids and a second wick having a plurality of second voids. The first wick rises from the flat surface and is fixed to the flat surface. The second wick is formed of a sintered body of powders and covers a surface of the first wick. Each of the plurality of second voids is smaller on average than each of the plurality of first voids.

Abstract: A housing unit includes: a linear material; and a housing body that houses the linear material. In the housing body, winding regions in which the linear material is wound are disposed in a circumferential direction. The linear material is wound in a figure eight in a first region pair constituted by a pair of the winding regions. The linear material is wound in a figure eight in a second region pair constituted by a pair of the winding regions that are different from the winding regions constituting the first region pair.

Abstract: An aluminum alloy conductive wire that includes 0.15 mass % or more and 0.25 mass % or less of Si; 0.6 mass % or more and 0.9 mass % or less of Fe; 0.05 mass % or more and 0.15 mass % or less of Cu; 0.2 mass % or more and 2.7 mass % or less of Mg, and 0.03 mass % or less in total of Ti, V, and B. The aluminum alloy conductive wire has tensile strength of equal to or less than T1 MPa represented by T1=59.5 ln(x)+231 and conductivity of equal to or more than C % IACS represented by C=1.26x2?11.6x+63.4 in a case where a content rate of Mg in the aluminum alloy conductive wire is x mass %.

Abstract: An optical computing device includes a filter, through which light passes, and an optical diffraction element group that performs optical computing. The optical diffraction element group includes one or more optical diffraction elements having microcells, each of the microcells having an independently set thickness or a refractive index. After passing through the filter, the light first enters a first optical diffraction element among the one or more optical diffraction elements. The filter selectively transmits light in a direction that has an angle, with respect to an optical axis of the first optical diffraction element, that is less than or equal to a specific angle determined by the filter.

Abstract: An optical input/output device includes: one or more multicore fibers each comprising one or more transmitting cores and one or more receiving cores; first transmitting single-core fibers whose number is equal to a total number of the transmitting cores; first receiving single-core fibers whose number is equal to a total number of the receiving cores in all the multicore fibers; a fan-in/fan-out device that optically couples each core of the first transmitting single-core fibers and each of the transmitting cores at one end of a respective one of the first transmitting single-core fibers, and optically couples each of the first receiving single-core fibers and each of the receiving cores at one end of a respective one of the first receiving single-core fibers; and a transmission/reception connector comprising connector ports whose number is equal to a total number of the first transmitting single-core fibers and the first receiving single-core fibers.

Abstract: An optical computing device includes: an optical modulation element including cells with independently configurable amounts of modulation; and a reflector. The optical modulation element is configured with N (N is a natural number not less than 2)-computing regions A1, A2, . . . , AN. The computing region A1 performs optical computing by modulating and reflecting incident light. Each computing region Ai (i is a corresponding natural number not less than 2 and not more than N) other than the computing region A1 performs the optical computing by modulating and reflecting signal light that has been modulated and reflected by a computing region Ai?1 and then reflected by the reflector.

Abstract: An optical fiber includes a glass portion, a primary coating layer, and a secondary coating layer. In the optical fiber, a value of microbend loss characteristic factor F?BL_G?? is 6.1 ([GPa?1·?m?2.5/rad8]·10?12) or less when represented by F?BL_G??=F?BL_G×F?BL_??, where F?BL_G is geometry microbend loss characteristic and F?BL_?? is optical microbend loss characteristic.

Abstract: An optical fiber fuse protection device includes an upstream optical fiber disposed on an upstream side, a downstream optical fiber disposed on a downstream side, and a wall interposed between a part of the upstream optical fiber and a part of the downstream optical fiber. The downstream optical fiber is fusion-spliced to the upstream optical fiber and is made of a single optical fiber or a plurality of optical fibers fusion-spliced to each other.

Abstract: A laser device includes a light source, an optical fiber, a cable coating, an optical connector, a pair of disconnection detection lines, a pair of open detection lines, and a determination portion. The light source outputs a laser beam. The optical fiber propagates the laser beam. The optical fiber is inserted into the cable coating. The optical connector is connected to a tip of the cable coating. The pair of disconnection detection lines include a first disconnection detection line and a second disconnection detection line. The pair of open detection lines include a first open detection line and a second open detection line.

Abstract: An optical combiner includes: an optical fiber bundle formed by a plurality of first optical fibers; and a second optical fiber including an end surface joined to an end surface of the optical fiber bundle by fusion-splicing. The plurality of first optical fibers includes a predetermined first optical fiber and other first optical fibers. The predetermined first optical fiber is composed of one or more materials having higher softening temperatures than one or more materials of the other first optical fibers.

Abstract: A laser module includes: a first laser diode that emits a first light beam having a first wavelength; a second laser diode that emits a second light beam having a second wavelength different from the first wavelength; a fast-axis collimating lens disposed corresponding to each of the first and second laser diodes to collimate a fast-axis direction of each of the first and second light beams emitted from each of the first and second laser diodes; a slow-axis collimating lens disposed corresponding to each of the first and second laser diodes to collimate a slow-axis direction of each of the first and second light beams emitted from each of the first and second laser diodes; and a wavelength combining element including a volume Bragg grating (VBG) or a diffraction grating.

Abstract: An optical fiber cable includes: a sheath; and a core that is housed in the sheath and includes optical fibers. Recesses and protrusions are disposed alternately in a circumferential direction on an outer circumferential surface of the sheath. The optical fiber cable has a compressive strength of 12.8 N/mm2 or greater and 32.4 N/mm2 or less.

Abstract: Wiring and a wiring path of a feed line for feeding power to a radiation element is simplified. An array antenna includes a first conductive pattern layer, first dielectric layer, conductive ground layer, second dielectric layer, second conductive pattern layer, third dielectric layer, and radiation element pattern layer that are layered in this order. The radiation element pattern layer includes radiation element pairs arranged in a two-dimensional array pattern. Each of the radiation element pairs includes a first radiation element and a second radiation element arranged side by side with an interval therebetween. The second conductive pattern layer includes branch feed lines arranged in a two-dimensional array pattern to correspond to the radiation element pairs, respectively. The first conductive pattern layer includes feed lines corresponding to the branch feed lines, respectively.

Abstract: An optical fiber includes a glass portion, a primary coating layer, and a secondary coating layer. In the optical fiber, a value of microbend loss characteristic factor F?BL_GO is 2.6 ([GPa?1·?m?10.5·dB/turn]·10?27) or less, when represented by F?BL_GO=F?BL_G×F?BL_O by using geometry microbend loss characteristic F?BL_G and optical microbend loss characteristic F?BL_O.

Abstract: A jig for a fusion splicer mountable on a heater of the fusion splicer includes: a plate part configured to face a heating part of the heater; a first retainer, configured to face a first clamp of the fusion splicer that is disposed outside of the heating part along a longitudinal direction of an object to be heated, and further configured to retain a first member extending from a first end of the object along the longitudinal direction; and a second retainer, configured to face a second clamp disposed on a side of the heating part opposite to the first clamp along the longitudinal direction, and further configured to retain a second member extending from a second end of the object along the longitudinal direction.