Abstract: The present disclosure relates to an optical transmission system that transmits signal light by using a multi-core optical fiber having two or more cores as transmission paths, the optical transmission system including two or more transmitters that transmit signal light to adjacent cores, in opposite directions, of the cores, and two or more pump light oscillators that inject pump light into the same cores as transmission cores to which the signal light is transmitted of the adjacent cores such that the pump light propagates in the same directions as or directions reverse to the directions of the signal light, and perform distributed Raman amplification of the signal light by using the pump light, in which a signal light gain of the signal light transmitted from the transmitters is set such that a signal intensity ratio to a crosstalk noise intensity leaked from the adjacent transmission cores is high.

Abstract: An object of the present disclosure is to provide an optical fiber having a simple structure, as well as attaining removal of loss components generated in an electric field part oozing out to a core-clad interface or a clad region and reduction in scattering loss generated from an interface with the clad region. The present disclosure relates to an optical fiber including a core for propagating light, a cladding disposed around the core, an air layer between the core and the cladding, and two or more bridges for supporting the core in the air layer.

Abstract: An object of the present invention is to provide an air conditioner unit that can fully demonstrate the sterilization effect on air with a large flow rate, even by a method of irradiating a filter and a coil with ultraviolet light. The air conditioner unit according to the present invention includes a filter 20 through which air passes, a plurality of optical fibers 16 arranged in such a manner that one ends thereof are close to a surface of the filter 20 and arranged at predetermined intervals, and a light source 30 that supplies ultraviolet light from the other end of each of the optical fibers 16. Since the intensity of the light is inversely proportional to the square of the distance from the light source, if the same sterilization effect is to be obtained, the shorter the irradiation distance, the smaller the irradiation intensity of the ultraviolet light can be.

Abstract: An object of the present invention is to provide an optical transmission system capable of reducing system costs and reducing waste of output power of a light source. The optical transmission system according to the present invention includes an ultraviolet light source part 11a having a light emitting diode (LED) that outputs ultraviolet light, an optical transmission line 26 that propagates the ultraviolet light through a plurality of cores of a multi-core optical fiber or a plurality of cores of a bundle optical fiber obtained by bundling a plurality of single-core optical fibers, and an optical system 11c that narrows down a spot shape of the ultraviolet light output from the LED to a size including all of the plurality of cores in an optical axis direction, and causes the ultraviolet light to enter the plurality of cores.

Abstract: An object of the present invention is to provide an ultraviolet light irradiation sheet that can be decontaminated regardless of a shape of an object to be decontaminated. An ultraviolet light irradiation sheet (50) includes an optical fiber (20) which emits a part of propagating light from a side surface or an end surface; and a deformable sheet (10) which incorporates the optical fiber (20). The ultraviolet light irradiation sheet uniformly or partially irradiates ultraviolet light from a sheet surface. Therefore, by covering the object to be sterilized with the ultraviolet light irradiation sheet, a material having a complicated shape or an amorphous shape can be irradiated with the ultraviolet light without making a shade. Since the ultraviolet light irradiation sheet does not diffuse bacteria and viruses by wind, the sterilization of the object to be sterilized can be performed without forming a closed space.

Abstract: An object of the present invention is to provide a photocatalytic sheet configured to perform disinfection independent of the state of external light. A photocatalytic sheet 50 according to the present invention includes a sheet 10 having a photocatalytic layer 17 on one surface, and an optical fiber 20 embedded in the sheet 10 and configured to supply ultraviolet light UV from inside of the sheet 10 to the photocatalytic layer 17. In the photocatalytic sheet, ultraviolet light is supplied from the optical fiber disposed in the sheet to the photocatalytic layer coated on the surface of the sheet (ultraviolet light is supplied from the back of the photocatalytic layer). This configuration allows for disinfection independent of the state of external light.

Abstract: An object of the present invention is to provide a banknote disinfection system configured to disinfect banknotes in a general-purpose banknote handling device without making a significant change in the structure of the general-purpose device. The banknote disinfection system 300 includes a conveyance mechanism configured to convey a banknote 50 using a plurality of rollers 12 and an optical fiber 20 configured to emit ultraviolet light to a surface of the banknote 50 conveyed by the conveyance mechanism. An optical fiber is thin, has many length options, and is flexible. With these features of the optical fiber, the optical fiber can be routed inside of, for example, an automatic teller machine to irradiate the banknotes moving inside the device with ultraviolet light.

Abstract: An object of the present invention is to provide an ultraviolet light irradiation system that is easy to operate and can avoid degradation of a material due to ultraviolet light. An ultraviolet light irradiation system according to the present invention includes: one ultraviolet light source unit 11 that generates ultraviolet light; an irradiation unit 13 that irradiates a desired portion (irradiation portion ste) with the ultraviolet light in a limited manner; an optical fiber 14 that propagates the ultraviolet light from the ultraviolet light source unit 11 to the irradiation unit 13; a sensing unit 16 that monitors a state of the irradiation portion ste and outputs the state as monitoring information; and an irradiation control unit 15 that controls output of the ultraviolet light from the ultraviolet light source unit 11 on the basis of the monitoring information.

Abstract: An object of the present invention is to provide an air conditioner unit that allows for greater flexibility in designing the shape of the unit and is capable of reducing the cost of lamp replacement. An air conditioner unit according to the present invention includes an optical fiber group 17 formed by bundling a plurality of optical fibers 16 emitting a part of propagating light from side faces thereof; an air duct 10 that incorporates the optical fiber group 17 in a space 13 through which air passes; and a light source 30 that supplies ultraviolet light to each of the optical fibers 16. Since the intensity of the light is inversely proportional to the square of the distance from the light source, if the same sterilization effect is to be obtained, the irradiation intensity of the ultraviolet light can be reduced when the irradiation distance is shorter.

Abstract: An object of the present invention is to provide an ultraviolet optical transmission system in which cutting of an optical fiber or a complicated procedure is not necessary when an optical fiber is exchanged.

Abstract: An object of the present invention is to provide an ultraviolet light irradiation system and an ultraviolet light irradiation method having a P-MP configuration capable of obtaining a predetermined effect such as sterilization. An ultraviolet light irradiation system 301 according to the present invention includes an ultraviolet light source unit 11 that generates ultraviolet light, N (N is a natural number) irradiation units 13 that irradiate a desired site (irradiation target region ste) with the ultraviolet light, an optical switch 12 that switches the ultraviolet light to each of paths 14 to the irradiation units 13, and a switching control unit 15 that controls a switching operation of the optical switch 12 so as to give an opportunity to be supplied with an integrated light amount per unit time equal for each of the paths 14 on the basis of a transmission loss of the ultraviolet light for each of the paths 14 and an irradiation area where the irradiation unit 13 irradiates the ultraviolet light.

Abstract: An object of the present invention is to provide an ultraviolet light irradiation system and an ultraviolet light irradiation method, each of which is capable of reducing deterioration over time of transmission loss characteristics of an optical fiber due to ultraviolet rays and preventing a decrease in ultraviolet ray irradiation power.

Abstract: An object of the present invention is to provide an ultraviolet light irradiation system and an ultraviolet light irradiation method which can perceive a state of a region where ultraviolet light is irradiated to output/block the ultraviolet light. An ultraviolet light irradiation system 301 according to the present invention includes an ultraviolet light source unit 11 that produces ultraviolet light, an N (N is a natural number) irradiation unit 13 that irradiates an irradiation target region Ar with the ultraviolet light, a sensor unit 31 that detects whether or not an object that should avoid exposure is present in the irradiation target region Ar, and a blocking unit 30 that stops, in a case where the object that should avoid exposure is present in the irradiation target region Ar, irradiation of the ultraviolet light from the irradiation unit 13 to the irradiation target region Ar.

Abstract: An object of the present invention is to provide an evaluation method and an evaluation device for easily determining whether or not a structural parameter of a multi-core fiber satisfies a desired connection loss value (a specification). The evaluation method according to the present invention includes a step of measuring center coordinates of each core with the center coordinates when a clad is approximated by a circle as an origin in an observed cross-sectional structure of the multi-core fiber to be objected, obtaining a length of a line segment connecting the origin and the center of each core and an angle formed by two line segments connecting the origin and two adjacent cores, and judging whether or not a desired connection loss characteristic is satisfied on the basis of whether or not the values satisfy a predetermined determination formula.

Abstract: An object of the present invention is to achieve a low delay core applicable to a Master channel of a Master-Slave CPE (MS-CPE) transmission method with a general-purpose refractive index distribution structure. An optical fiber according to the present invention is a single-mode optical fiber, and has an SI-type refractive index distribution structure, in which a clad region relative refractive index difference ? (%) with respect to a core region refractive index, a radius a (?m) of the core region, and a group delay time difference ?? between the Master channel and the Slave channel satisfy “Mathematical Expression 19” and “Mathematical Expression 20”, or has a W-type refractive index distribution structure, in which a mode field diameter MFD is 9.5 to 10.

Abstract: An object of the present invention is to provide an optical transmission system capable of satisfying XT required by a modulation system even if there is an inter-core loss difference in an MCF.

Abstract: An object of the present disclosure is to alleviate deterioration of transmission characteristics of a fiber due to transmission of ultraviolet light, and to eliminate complication of operation due to frequent replacement of an optical fiber in which deterioration has occurred. The present disclosure is an ultraviolet light irradiation system including: an optical transmission unit that propagates ultraviolet light using a plurality of optical transmission lines; an ultraviolet light source unit that inputs ultraviolet light to each of the optical transmission lines with arbitrary power; and an irradiation unit that irradiates a target location with the ultraviolet light propagated through the plurality of optical transmission lines.

Abstract: An object of the present invention is to provide an ultraviolet light irradiation system and an ultraviolet light irradiation method which are not limited in an ultraviolet light irradiation region and can be introduced economically. The present ultraviolet light irradiation system is a system configured to connect a single ultraviolet light source part and an irradiation part installed in the vicinity of an object place to be sterilized or the like by the optical cable formed by bundling a plurality of optical fibers (the single-core or the multi-core) or the multi-core optical fiber. Since the optical fiber is very thin and does not require power supply for transmitting the ultraviolet rays, even in a fine place where a person or a robot cannot enter, the ultraviolet light can be irradiated by laying the optical fiber or the optical cable.

Abstract: The present invention is to provide a multi-core optical fiber that can expand its transmission wavelength band, and extend its transmission distance by reducing crosstalk, and also provide a method for designing the multi-core optical fiber. A multi-core optical fiber according to the present invention includes: four cores that are arranged in a square lattice pattern in a longitudinal direction; and a cladding region that is formed around the outer peripheral portions of the cores and has a lower refractive index than the cores, the absolute value of the relative refractive index difference between the cores and the cladding region being represented by ?. In the multi-core optical fiber, the diameter of the cladding region is 125 ± 1 µm, the cutoff wavelength is 1.45 µm or shorter, the mode field diameter MFD at a wavelength of 1.55 µm is 9.5 to 10.0 µm, the bending loss at a wavelength of 1.625 µm and with a bending radius of 30 mm is 0.

Abstract: It is an object of the present disclosure to reduce the risk of information exploitation by a malicious third party while allowing communication data to be demodulated in real time.