Hitachi Metals, Ltd.

Ntt Communications Corporation

Hitachi Cable, Inc.

Advanced Cable Systems Corp.

Takao Nishikawa

Kanako Suzuki

Toshiyuki Suzuki

Yoshihiro Nakatani

Koki Hirano

Seiji Kojima

Kojiro Ito

Mikio Ohkoshi

Wataru Ohnuki

Toshihiko Ishikawa

Toshio Sakai

Tetsuya Sueoka

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.

Optical fiber monitoring system

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.

Duplex LC communication light detecting adapter and duplex LC communication light detecting structure

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.

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 &#x3bc;m or more and 140 &#x3bc;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.

Communication light detecting device

Growing community of inventors

Tokyo, Japan

Takao Nishikawa