Abstract: An optical amplification system includes: three or more nodes; a multi-core fiber having a plurality of cores, the multi-core fiber being used in at least a partial segment of the connection between the nodes; an amplification light input unit configured to input amplification light to a core of the plurality of cores of the multi-core fiber; an amplification unit configured to amplify communication light transmitted through at least one core of the plurality of cores of the multi-core fiber using the amplification light, the amplification unit being provided in the nodes or between the nodes; and an amplification light coupling unit configured to couple the amplification light input by the amplification light input unit to the amplification unit.

Abstract: A communication system includes three or more nodes, and a multi-core fiber having a plurality of cores, the multi-core fiber being used in at least a partial segment of a connection between the nodes, wherein each of nodes includes: a fault information transmitting device configured to transmit fault information indicating that a fault has occurred in a communication path between one node and another node of the nodes when it is detected that it is not possible to perform communication between the one node and the another node; and a fault location specifying device configured to specify a section between nodes in which a fault has occurred on the basis of the fault information received from the fault information transmitting device provided in each of the nodes

Abstract: A node included in an optical power supply system which includes three or more nodes and a multi-core fiber having a plurality of cores, the plurality of cores being used in at least a partial segment of the connection between the nodes includes: a power supply light dropping unit configured to drop a portion or all of a power supply light from one core of the plurality of cores of the multi-core fiber; a photoelectric conversion unit configured to convert the portion or all of the power supply light dropped by the power supply light dropping unit to an electrical signal; and a power supply target facility configured to operate with the electrical signal converted by the photoelectric conversion unit.

Abstract: A communication system includes three or more nodes and a multi-core fiber having a plurality of cores, the multi-core fiber being used in at least a partial segment of the connection between the nodes is provided. One node of the nodes is connected to the multi-core fiber and includes a connector configured to add and drop a signal to and from an allocated core exclusively allocated from among the cores as a communication path between the one node and another node of the nodes and/or configured to relay a signal transmitted through another core of the cores allocated for communication between other nodes in the multi-core fiber connected to the one node, and a relative positional relationship between a connection position of the allocated core in which a signal is added or dropped in the connector and a connection position of another core in which a signal is relayed in the connector is the same for all of the nodes connected to the multi-core fiber.

Abstract: A transmission quality estimation system includes, three or more nodes and a transmission quality estimation device configured to estimate, transmission quality. A multi-core fiber having a plurality of cores, the multi-core fiber being used in at least a partial segment of a connection between the nodes. A node of the nodes includes a core connection unit configured to drop, add or relay light transmitted from, to or to each of to the plurality of cores of the multi-core fiber. The transmission quality estimation device includes an estimation unit configured to estimate transmission quality between the nodes on the basis of a transmission quality measurement light dropped by the core connection unit.

Abstract: An optical transmitter includes: an optical modulator including an MZ interferometer, a drive signal input electrode, and a phase difference adjustment bias electrode; a drive amplifier; a phase difference adjustment bias voltage generator; a dithering unit that applies dithering of a predetermined frequency to an amplitude of a drive signal or to a half-wave voltage of the MZ interferometer; a controller unit that changes a phase difference adjustment bias voltage based on a modulation component of the frequency that is superimposed onto modulated light that is output from the optical modulator, to thereby bias the MZ interferometer to a null point; and a synchronous detection circuit that synchronously detects the modulation component of the frequency that is superimposed onto the modulated light. The controller unit changes the phase difference adjustment bias voltage such that a result of synchronous detection by the synchronous detection circuit becomes maximized or minimized.

Abstract: A transport apparatus includes: a client signal transceiving unit which transceives a client signal; a line signal transceiving unit which performs electric-optic conversion on a line signal to be transmitted, transmits an optical line signal, performs optic-electric conversion on a received line signal, and outputs an electrical line signal; and a plurality of signal processing units which perform signal processing on the client signal to generate the line signal to be transmitted and perform signal processing on the electrical line signal to generate the client signal.

Abstract: A nitride semiconductor ultraviolet light emitting device 1 is configured such that a nitride semiconductor ultraviolet light emitting element 10 is mounted on a base 30 by flip-chip mounting and sealed with an amorphous fluororesin whose terminal functional group is perfluoroalkyl group. The nitride semiconductor ultraviolet light emitting element 10 includes a sapphire substrate 11, a semiconductor laminated portion 12 of an AlGaN-based semiconductor laminated on a front surface of the sapphire substrate 11, an n electrode 13, a p electrode 14 and a back surface covering layer 15 which is formed on a back surface of the sapphire substrate 11 and transmits ultraviolet light.

Abstract: A nitride semiconductor ultraviolet light-emitting element comprises an underlying portion that includes a substrate that is composed of sapphire and has a surface inclined to a (0001) surface so as to form a multi-step terrace, and an AlN layer formed on a surface of the substrate, and a light-emitting portion that is formed on a surface of the underlying portion and includes an active layer having an AlGaN based semiconductor layer. At least the AlN layer of the underlying portion, the active layer of the light-emitting portion, and each layer between the AlN layer and the active layer are formed by step flow growth in which a side surface of a multi-step terrace grows so as to achieve two-dimensional growth. The active layer has a quantum well structure including at least a well layer composed of AlGaN. The average roughness of a 25 ?m by 25 ?m region on a surface of the active layer is a thickness of the well layer or more and 10 nm or less.

Abstract: To prevent degradation of electrical characteristics caused by a resin filled between electrodes in an ultraviolet light-emitting operation, the present invention provides a base 10 that comprises an insulating base material 11 and two or more metal films 12 and 13 that are formed on one side of the insulating base material 11 and electrically separated from each other. The two or more metal films are formed to include an upper surface and a side wall surface that are covered by gold or a platinum group metal, to be capable of mounting thereon one or more nitride semiconductor light-emitting elements and the like, and to have, as a whole, a predetermined planar view shape including two or more electrode pads.

Abstract: To prevent degradation of electrical characteristics caused by a resin filled between electrodes in an ultraviolet light-emitting operation, there is provided a nitride semiconductor wafer having ultraviolet light-emitting elements on a substrate 12, each element including a semiconductor laminated portion 21 constituted by an n-type AlGaN layer 16, an active layer 17 composed of an AlGaN layer, and p-type AlGaN layers 19 and 20, an n-electrode 23, a p-electrode 22, a protective insulating film 24, first and second plated electrodes 25 and 26, and a fluororesin film 27. The p-electrode is formed on an upper surface of the p-type AlGaN layer in the first region R1 and the n-electrode is formed on an upper surface of the n-type AlGaN layer in the second region R2. The protective insulating film has openings for exposing at least parts of the n-electrode and the p-electrode.

Abstract: An ultraviolet light emitting device having high quality and high reliability is provided by preventing deterioration of electrical characteristics which is associated with an ultraviolet light emission operation and caused by a sealing resin.

Abstract: Accommodation design for wavelength and sub-? paths in a communication network is performed. If sub-? path accommodation is possible according to search for a wavelength path present in a single-hop logical route, the accommodation in the wavelength path is executed. If sub-? path accommodation is possible according to search for a wavelength path present in a multi-hop logical route, a logical route is selected based on the wavelength path and the sub-? path is accommodated in the wavelength path. Additionally, each physical route suitable for the sub-? path accommodation is searched for. If the route can accommodate a wavelength path set in a single-hop logical route by available wavelength allocation, the sub-? path is accommodated in the wavelength path. Furthermore, routes in consideration of overlapping of nodes, pipelines, and links and operation rate are selected based on information about the start and end nodes of each of redundant routes.

Abstract: There is provided a nitride semiconductor ultraviolet light-emitting element capable of efficiently releasing a waste heat generated in an ultraviolet light emitting operation. The nitride semiconductor ultraviolet light-emitting element includes a semiconductor laminated portion 11 having an n-type AlGaN layer 6, an active layer 7 of an AlGaN layer, and p-type AlGaN layers 9 and 10; an n electrode 13; a p electrode 12; a protective insulating film 14, and a first plated electrode 15 formed by a wet plating method and composed of copper or alloy containing copper as a main component. The semiconductor laminated portion 11 is formed in a first region R1, and the p electrode is formed on the portion 11. An upper surface of the n-type AlGaN-based semiconductor layer 6 is exposed in a second region, and the n electrode 13 is formed on the upper surface. The protective insulating film 14 has openings for exposing at least one part of the n electrode 13 and at least one part of the p electrode 12.

Abstract: Accommodation design for wavelength and sub-? paths in a communication network is performed. If sub-? path accommodation is possible according to search for a wavelength path present in a single-hop logical route, the accommodation in the wavelength path is executed. If sub-? path accommodation is possible according to search for a wavelength path present in a multi-hop logical route, a logical route is selected based on the wavelength path and the sub-? path is accommodated in the wavelength path. Additionally, each physical route suitable for the sub-? path accommodation is searched for. If the route can accommodate a wavelength path set in a single-hop logical route by available wavelength allocation, the sub-? path is accommodated in the wavelength path. Furthermore, routes in consideration of overlapping of nodes, pipelines, and links and operation rate are selected based on information about the start and end nodes of each of redundant routes.

Abstract: There is provided a nitride semiconductor ultraviolet light-emitting element capable of efficiently releasing a waste heat generated in an ultraviolet light emitting operation. The nitride semiconductor ultraviolet light-emitting element includes a semiconductor laminated portion 11 having an n-type AlGaN layer 6, an active layer 7 of an AlGaN layer, and p-type AlGaN layers 9 and 10; an n electrode 13; a p electrode 12; a protective insulating film 14, and a first plated electrode 15 formed by a wet plating method and composed of copper or alloy containing copper as a main component. The semiconductor laminated portion 11 is formed in a first region R1, and the p electrode is formed on the portion 11. An upper surface of the n-type AlGaN-based semiconductor layer 6 is exposed in a second region, and the n electrode 13 is formed on the upper surface. The protective insulating film 14 has openings for exposing at least one part of the n electrode 13 and at least one part of the p electrode 12.

Abstract: A transport apparatus includes: a client signal transceiving unit which transceives a client signal; a line signal transceiving unit which performs electric-optic conversion on a line signal to be transmitted, transmits an optical line signal, performs optic-electric conversion on a received line signal, and outputs an electrical line signal; and a plurality of signal processing units which perform signal processing on the client signal to generate the line signal to be transmitted and perform signal processing on the electrical line signal to generate the client signal.

Abstract: A nitride semiconductor light emitting element comprises a sapphire substrate, and a light emitting element structure portion that has a plurality of nitride semiconductor layers formed on the sapphire substrate. The nitride semiconductor light emitting element is a back-surface-emitting type nitride semiconductor light emitting element that outputs light from the light emitting element structure portion to an outside of the element through the sapphire substrate. The nitride semiconductor light emitting element is divided into a chip whose planarly-viewed shape is a square or a rectangle. A thickness of the sapphire substrate is 0.45 to 1 times an average length of sides of the planarly-viewed shape of the chip.

Abstract: Performing power transfer to a plurality of power receiving devices, a power transmission device allocates one of a plurality of channels to perform wireless power transfer to a power receiving device in response to a power transmission request transmitted from the power receiving device designating one or more of the plurality of the channels having different frequencies. In a case where a power transmission request using the first channel is received from a second power receiving device, the device stops power transfer to the first power receiving device using the first channel, starts power transfer to the first power receiving device using a channel other than the first channel and starts power transfer to the second power receiving device using the first channel.

Abstract: The present invention provides a method for producing a template for epitaxial growth, the method including: a surface treatment step of dispersing Ga atoms on a surface of a sapphire substrate; and an AlN growth step of epitaxially growing an AlN layer on the sapphire substrate, wherein in a Ga concentration distribution in a depth direction perpendicular to the surface of the sapphire substrate in an internal region of the AlN layer excluding a near-surface region up to a depth of 100 nm from the surface of the AlN layer, which is obtained by secondary ion mass spectrometry, a position in the depth direction where the Ga concentration takes the maximum value is present in a near-interface region located between the interface of the sapphire substrate and a position at 400 nm spaced apart from the interface to the AlN layer side, and the maximum value of the Ga concentration is 3×1017 atoms/cm3 or more and 2×1020 atoms/cm3 or less.