Abstract: A communication light detection device includes a housing provided with plural first optical adapters and plural second optical adapters, and plural light detection portions provided in connection portions respectively for optically connecting together a first optical fiber provided in the housing and extended from the first optical adapters into the housing and a second optical fiber extended from the corresponding second optical adapters into the housing, to detect light transmitted via both the optical fibers. The light detection portions each include a light leak portion provided in the connection portions to allow light to partially leak, a light receiving element to detect the light leaked at the light leak portion, and a case including a recessed groove for accommodating the connection portions and not transmitting light. A circuit board is included with the light receiving elements mounted thereon together, and is provided to close openings of the recessed grooves together.

Abstract: A communication light detection device includes a housing provided with plural first optical adapters and plural second optical adapters, and plural light detection portions provided in connection portions respectively for optically connecting together a first optical fiber provided in the housing and extended from the first optical adapters into the housing and a second optical fiber extended from the corresponding second optical adapters into the housing, to detect light transmitted via both the optical fibers. The light detection portions each include a light leak portion provided in the connection portions to allow light to partially leak, a light receiving element to detect the light leaked at the light leak portion, and a case including a recessed groove for accommodating the connection portions and not transmitting light. A circuit board is included with the light receiving elements mounted thereon together, and is provided to close openings of the recessed grooves together.

Abstract: An optical fiber monitoring system monitors an inter-building optical fiber connecting a first building and a second building. The optical fiber monitoring system includes a first visualization panel provided in the first building and optically connected to an one end of the inter-building optical fiber, a second visualization panel provided in the second building and optically connected to an other end of the inter-building optical fiber, and a monitoring light source provided in the first building to input a monitoring light into the inter-building optical fiber. The first visualization panel includes a first photosensor that partially leaks the monitoring light inputted into the inter-building optical fiber from the monitoring light source and detects an amount of a leaked light. The second visualization panel includes a second photosensor that partially leaks a light from the inter-building optical fiber and detects amount of a leaked light.

Abstract: An optical fiber monitoring system monitors an inter-building optical fiber connecting a first building and a second building. The optical fiber monitoring system includes a first visualization panel provided in the first building and optically connected to an one end of the inter-building optical fiber, a second visualization panel provided in the second building and optically connected to an other end of the inter-building optical fiber, and a monitoring light source provided in the first building to input a monitoring light into the inter-building optical fiber. The first visualization panel includes a first photosensor that partially leaks the monitoring light inputted into the inter-building optical fiber from the monitoring light source and detects an amount of a leaked light. The second visualization panel includes a second photosensor that partially leaks a light from the inter-building optical fiber and detects amount of a leaked light.

Abstract: A communication light visualization structure includes a duplex LC communication light visualization adapter including an opening portion connected to a first light extraction space and a second light extraction space, and a guide groove formed in the opening portion; and a duplex LC communication light detector including a base portion that has the same cross-sectional shape as the opening portion, a first light receiver that receives first leakage light, a second light receiver that receives second leakage light, a light blocking wall that shields the first light extraction space and the second light extraction space from each other, and a display portion that individually displays a communication status of a first communication path and a second communication path. The guide groove is formed at a position such that cross sections of the opening portion and the base portion fit together in only one direction.

Abstract: A communication light visualization module includes multiple communication light visualization adapters into which an optical connector is fitted and to which the optical connector is optically connected and a housing that houses the communication light visualization adapters in an arrangement manner. Each of the communication light visualization adapters includes a light extraction hole from which part of communication light transmitted through an optical communication path is extracted. The housing includes a common protection cover that collectively covers the light extraction holes of the plurality of communication light visualization adapters or collectively renders the light extraction holes uncovered.

Abstract: A communication light visualization structure includes a duplex LC communication light visualization adapter including an opening portion connected to a first light extraction space and a second light extraction space, and a guide groove formed in the opening portion; and a duplex LC communication light detector including a base portion that has the same cross-sectional shape as the opening portion, a first light receiver that receives first leakage light, a second light receiver that receives second leakage light, a light blocking wall that shields the first light extraction space and the second light extraction space from each other, and a display portion that individually displays a communication status of a first communication path and a second communication path. The guide groove is formed at a position such that cross sections of the opening portion and the base portion fit together in only one direction.

Abstract: A communication light visualization module includes multiple communication light visualization adapters into which an optical connector is fitted and to which the optical connector is optically connected and a housing that houses the communication light visualization adapters in an arrangement manner. Each of the communication light visualization adapters includes a light extraction hole from which part of communication light transmitted through an optical communication path is extracted. The housing includes a common protection cover that collectively covers the light extraction holes of the plurality of communication light visualization adapters or collectively renders the light extraction holes uncovered.

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 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: 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 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 core detaching tool for an optical fiber cable detaches one or more optical fiber tape units accommodated in a sheath of the optical fiber cable by tearing the sheath. The core detaching tool for an optical fiber cable is provided with a pair of cable holding parts, and a moving mechanism for moving the cable holding parts. A pair of projected parts are formed inside the cable holding parts, and a distance between the projected parts is greater than a long side face of a cross section of the optical fiber tape unit. The optical fiber tape unit can be separated and detached from the sheath in intermediate post-branching of the optical fiber cable without increasing a transmission loss.