Abstract: A repeater includes a plurality of input-side connectors and a plurality of output-side connectors corresponding to the input-side connectors that are configured such that communication cables connected to the input-side connectors are connected to other communication cables connected to the output-side connectors, and a detection indicating circuit provided between the input-side connectors and the corresponding output-side connectors. The detection indicating circuit includes a detection circuit branching, extracting and outputting a portion of signal transmitted between the input-side connectors and the corresponding output-side connectors, and an indicating circuit for indicating an establishment of information communication according to an output from the detection circuit.

Abstract: A communication light detecting structure includes a communication optical fiber configured to transmit communication light; a leakage optical fiber optically connected to the middle of the communication optical fiber via optical connection portions, the leakage optical fiber being different in core refractive index from the communication optical fiber; and a light detecting unit configured to detect part of the communication light leaking from the optical connection portions as leakage light. A communication light detecting optical connector includes the communication light detecting structure. A communication light detecting optical cable includes the communication light detecting structure. The communication optical fiber and the leakage optical fiber may have the same core diameter. The communication optical fiber and the leakage optical fiber may have the same cladding refractive index.

Abstract: A communication light detecting optical module includes a plurality of optical transmission lines each including a light drawing portion to draw a leak portion of communication light being transmitted in the each of the plurality of optical transmission lines as a leaky light, and a multifiber connector with the plurality of optical transmission lines being arranged side by side, inserted and fixed therein. The multifiber connector includes an adhesive filled portion exposing the plurality of optical transmission lines and being filled with an adhesive to fix the plurality of optical transmission lines. The plurality of optical transmission lines are being inserted and fixed in the multifiber connector in such a manner that the light drawing portions are being arranged in the adhesive filled portion.

Abstract: A communication light detector is configured to draw a leak portion of communication light being transmitted via a communication light detecting adapter as a leaky light, receive the leaky light, and detect whether the communication light is being transmitted via the communication light detecting adapter or not. The communication light detector includes a light receiving element configured to receive the leaky light, and an optical filter configured to pass only the leaky light toward the light receiving element.

Abstract: A duplex LC communication light detecting adapter includes an adapter main body to form two parallel optical transmission lines therein when a duplex LC connector is inserted, the adapter main body including a side in which a light extraction hole is formed, the light extraction hole being located at a vertex of a isosceles triangle having a base that is a line segment connecting centers of the two optical transmission lines in a cross section and opened in a direction perpendicular to the line segment, and a sleeve holder formed integrally with the adapter main body to hold a sleeve that houses a ferrule of the duplex LC connector. The sleeve holder includes an opening section that is opened toward the light extraction hole in a range of more than 30 degrees to less than 120 degrees relative to the line segment in a cross section.

Abstract: A duplex LC communication light detecting adapter for forming two parallel optical transmission lines therein when a duplex LC connector is inserted so as to extract as a leak light a portion of communication light transmitting through the optical transmission lines, including an adapter main body that is opaque to light. The adapter main body includes a first space defined by a first wall and isolated from other spaces to arrange a first optical transmission line of the two optical transmission lines, a first light extraction hole for extracting the leak light from the first space, a second space defined by a second wall and isolated from other spaces to arrange a second optical transmission line of the two optical transmission lines, and a second light extraction hole for extracting the leak light from the second space.

Abstract: A communication light detector is removably attached to a communication light visualizing adaptor with a light extraction hole so as to detect whether a communication light is transmitted through the communication light visualizing adaptor. The detector includes a detector main body including a bottom surface that faces the light extraction hole, mounts a light-receiving element and is formed so as to adapt to a first communication light visualizing adaptor, and an attachment that includes a front surface facing the bottom surface, a back surface facing the light extraction hole and a though-hole penetrating from the front surface to the back surface so that the light-receiving element is exposed from the front surface to the back surface, the front surface being formed so as to adapt to the bottom surface and the back surface being formed so as to adapt to a second communication light visualizing adaptor.

Abstract: A communication light detection adapter includes an adapter main body in which a light extraction hole is formed, a sliding lid attached to the adapter main body so as to slide between a closed position to close the light extraction hole and an open position to open the light extraction hole, and an energizing member to apply a pressure to the sliding lid in a direction from the open position toward the closed position.

Abstract: A communication light detecting structure includes a communication optical fiber configured to transmit communication light; a leakage optical fiber optically connected to the middle of the communication optical fiber via optical connection portions, the leakage optical fiber being different in core refractive index from the communication optical fiber; and a light detecting unit configured to detect part of the communication light leaking from the optical connection portions as leakage light. A communication light detecting optical connector includes the communication light detecting structure. A communication light detecting optical cable includes the communication light detecting structure. The communication optical fiber and the leakage optical fiber may have the same core diameter. The communication optical fiber and the leakage optical fiber may have the same cladding refractive index.

Abstract: It is intended to provide base sequences participating in the regulation of the expression of a promoter. It is also intended to modify a promoter based on the base sequence data to give a modified promoter having a high expression activity. Namely, a modified promoter constructed by inserting a first DNA fragment containing CCAATNNNNNN (SEQ ID NO:1) (a first base sequence) and a second DNA fragment containing CGGNNNNNNNNNGG (SEQ ID NO:2) (a second base sequence) into a promoter functioning in a filamentous fungus, wherein N in the base sequence denotes A (adenine), G (guanine), C(cytosine), or T (thymine).

Abstract: An optical fiber has a single-layer coated optical fiber having an optical bare fiber including a core and a clad formed around the core, and a single coating layer provided around an outer periphery of the optical bare fiber, an inner coating layer provided around an outer periphery of the single-layer coated optical fiber, which contacts with the single coating layer, and an outer coating layer formed as a collective coating layer around an outer side of the inner coating layer. The inner coating layer has a Young modulus lower than a Young modulus of the single coating layer and a Young modulus of the outer coating layer.

Abstract: An optical fiber that has no bubbles in the ultraviolet ray curable resin filled inside the air holes to seal the end parts thereof, an end part processing method of the optical fiber, and an end part processing apparatus of the optical fiber, are provided. In an end part processing method of an optical fiber that is comprised of a core and a cladding formed around the core, the cladding having a refraction index lower than that of the core and has a plurality of air holes formed therein along the axis of the core, wherein the end part process of the optical fiber is to form sealed portions on the ends of the air holes by sealing them with ultraviolet ray curable resin, the method is characterized in that the sealed portion is formed by heating the end of the optical fiber.

Abstract: An optical fiber connecting part has a ferrule, and a guide bore penetrating through the ferrule and configured to guide an optical fiber to be inserted. The guide bore has a first bore provided at one end of the ferrule, through which the optical fiber is inserted into the ferrule, a second bore provided at another end of the ferrule, the second bore having an inner diameter smaller than an inner diameter of the first bore, and an intermediate bore provided between the first bore and the second bore to directly connect between the first bore and the second bore. A center axis of the second bore is shifted from a center axis of the first bore.

Abstract: A composite cable that is able to prevent both the unfastening of the cable end from the connector and the occurrence of the bending distortion of the optical fiber, to both of which the expansion and shrinkage of the overall sheath is responsible, is provided. The composite cable comprises a stranded wire that is a strand of a plurality of insulated conductors each of which is a conductor with insulation covering thereon, an optical fiber ribbon that has a plurality of optical fibers parallelly-arranged in a row, and an overall sheath that covers the stranded wire and the optical fiber ribbon in a bundle, wherein the composite cable has a deterrent positioned on outer side of the stranded wire and the optical fiber ribbon parallelly-arranged in a row along the width direction of the overall sheath for deterring expansion and shrinkage of the overall sheath.

Abstract: An optical switch includes a first connector holding an end of at least one optical fiber and a second connector holding respective ends of at least two optical fibers. The optical switch further includes a sliding mechanism faces a connecting surface of the first connector and a connecting surface of the second connector each other, to optically connect between the at least one optical fiber held in the first connector and one of the at least two optical fibers held in the second connector, and slides the connecting surface of the first connector and the connecting surface of the second connector relative to each other with keeping a facing state, and a spacer mechanism for preventing the respective end faces of the facing optical fibers held in the first and second connectors from contacting each other, or from contacting the connecting surfaces of the first and second connectors, respectively.

Abstract: An optical connector that permits an optical fiber ribbon to be led out in multiple directions and an optical fiber module that uses the optical connector are provided. The optical connector comprises a connector main body and a guide groove formed on the connector main body in which an optical fiber ribbon is arranged, wherein the guide groove is comprised of an end face holding slot, a vertical guiding face, an arcuate guiding face formed in arc-shape, and a positioning face for widthwise positioning and fixing the optical fiber ribbon and wherein the vertical guiding face and the arcuate guiding face and the positioning face define a space that opens toward a top face of the connector main body; and the optical fiber module comprises the optical fiber ribbon and the optical connector.

Abstract: A communication light detecting device interconnecting light transmission paths and collocated therebetween, comprises: an optical coupling body including a core portion for photo coupling with the light transmission paths, and a light extracting portion for extracting a part of the communication light as a leakage light; and a light detecting portion having a light receiving member for receiving the leakage light. The light extracting portion is preferable to possess a lower refractive index than that of the core portion. Besides, the light extracting portion is preferable to include a light detecting use groove with a groove width of 50 ?m or more and 140 ?m or less formed by cutting and separating the core portion. Besides, the light extracting portion is preferable to be the optical coupling body in which outer diameter of the core portion is different from the outer diameter of a core of the light transmission path.

Abstract: An optical fiber that has no bubbles in the ultraviolet ray curable resin filled inside the air holes to seal the end parts thereof, an end part processing method of the optical fiber, and an end part processing apparatus of the optical fiber, are provided. In an end part processing method of an optical fiber that is comprised of a core and a cladding formed around the core, the cladding having a refraction index lower than that of the core and has a plurality of air holes formed therein along the axis of the core, wherein the end part process of the optical fiber is to form sealed portions on the ends of the air holes by sealing them with ultraviolet ray curable resin, the method is characterized in that the sealed portion is formed by heating the end of the optical fiber.

Abstract: In an embodiment of the invention, an optical connector for optically coupling respective end faces of two optical fiber cables including an optical fiber composed of a core and a cladding includes a beat shrinkable tube, a cable insertion tube disposed in the heat shrinkable tube for inserting thereinto and butting the respective end faces of the two optical fiber cables, an uncured refractive index matching resin disposed between the beat shrinkable tube and the cable insertion tube, and a resin supply hole formed in the cable insertion tube for supplying the uncured refractive index matching resin to an inside of the cable insertion tube.

Abstract: An optical fiber has a single-layer coated optical fiber having an optical bare fiber including a core and a clad formed around the core, and a single coating layer provided around an outer periphery of the optical bare fiber, an inner coating layer provided around an outer periphery of the single-layer coated optical fiber, which contacts with the single coating layer, and an outer coating layer formed as a collective coating layer around an outer side of the inner coating layer. The inner coating layer has a Young modulus lower than a Young modulus of the single coating layer and a Young modulus of the outer coating layer.