Nippon Telegraph and Telephone Corporation

Morito Matsuoka

Akira Okada

Takashi Sakamoto

Kazuto Noguchi

Hiromasa Tanobe

Osamu Moriwaki

Yoshihisa Sakai

Kazutoshi Kato

Sen-ichi Suzuki

Ken'ichi Ono

Kenichi Ono

Ken-ichi Ono

Sen-Ichi Suzuki

An optical communication system is constructed which enables highly reliable and flexible connection to communication nodes connected to a path establishment circuit, by utilizing wavelength-routing characteristics of a path establishment circuit such as an arrayed waveguide grating. The optical communication system has multiple communication nodes having a signal output port and signal input port pair, and a path establishment circuit having multiple optical input ports and multiple optical output ports which are set so that optical signals input from the respective optical input ports are output to predetermined optical output ports corresponding to the wavelengths of the optical signals.

Optical communication system

An optical communication network system and a wavelength-routing device and a communication node therefor are provided which can easily increase the optical paths between communication nodes, which are capable of expanding transmission capacity, and which excel in flexibility and expandability. An optical signal within a wavelength band (&#x3bb;B&#xb1;&#x394;&#x3bb;) which has been transmitted from a predetermined communication node (-through-) is subjected to wavelength-band demultiplexing of the wavelength bands by wavelength-band demultiplexers (-through-) of a wavelength-routing device (), and is then subjected to wavelength-routing by arrayed-waveguide gratings (through) according to the wavelength bands, and furthermore is multiplexed with optical signals of other wavelength bands by wavelength-band multiplexers (-through-), and after having been outputted, is transmitted to a communication node. In this manner, by varying the wavelength band (&#x3bb;B&#xb1;&#x394;&#x3bb;) of the wavelength of the optical signal which is transmitted from the communication node, it becomes possible to establish a single optical path between the communication nodes for each wavelength band.

Optical communication network system, wavelength routing apparatus, communication node, optical path managing method for use in optical cross connect apparatus, and apparatus for that method

A fiber optic communication system includes a device of switching and setting wavelength of optical signals used in communication by network-node equipments, which sets the mapping of the wavelength of the optical signal used in communication by the network node equipments, and the input/output ports of an array waveguide grating (AWG), so as to construct a predetermined logical network topology by a plurality of network node equipments which are connected via optical fibers to the array waveguide grating that outputs optical signals inputted to optical input ports, to predetermined optical output ports in accordance with the wavelength thereof. As well as enabling a simple construction, it is easy to realize flexible network design, construction, and operation, and different network groups can also be easily connected to each other. Moreover, a fiber optic communication system having robust security and which can be stably operated even at the time of failure is realized at low cost.

Optical communication network system

An optical communication equipment comprises shared optical sourcesto be shared by communication nodes, the wavelengths of optical signalsare converted into desired wavelengths &#x3bb;a&#x2013;&#x3bb;d according to the addressed information of the corresponding optical label signalsby using the shared optical sourcesand routed to the addressed communication nodes without being converted into electrical signals by using the wavelength routing function of the cyclic-wavelength arrayed-waveguide grating (AWG). The load of each communication node can be reduced by incorporating the multi-wavelength optical sources, which can be shared among individual communication nodes, into the router. Further, each communication node is provided with an optical gate or the like for returning the optical signal to the communication node from which the optical signal has been transmitted through the routerin order to adjust the transmission time lag between the optical signal and the corresponding optical label signal by the controllers

Optical packet routing network system based on optical label switching technique

An optical communication equipment comprises shared optical sourcesto be shared by communication nodes, the wavelengths of optical signalsare converted into desired wavelengths &#x3bb;a&#x2013;&#x3bb;d according to the addressed information of the corresponding optical label signalsby using the shared optical sources, and routed to the addressed communication nodes without being converted into electrical signals by using the wavelength routing function of the cyclic-wavelength arrayed-waveguide grating (AWG). The load of each communication node can be reduced by incorporating the multi-wavelength optical sources, which can be shared among individual communication nodes, into the router. Further, each communication node is provided with an optical gate or the like for returning the optical signal to the communication node from which the optical signal has been transmitted through the routerin order to adjust the transmission time lag between the optical signal and the corresponding optical label signal by the controllers

An optical communication equipment comprises shared optical sources to be shared by communication nodes , the wavelengths of optical signals are converted into desired wavelengths &lgr; according to the addressed information of the corresponding optical label signals by using the shared optical sources and routed to the addressed communication nodes without being converted into electrical signals by using the wavelength routing function of the cyclic-wavelength arrayed-waveguide grating (AWG) . The load of each communication node can be reduced by incorporating the multi-wavelength optical sources, which can be shared among individual communication nodes, into the router . Further, each communication node is provided with an optical gate or the like for returning the optical signal to the communication node from which the optical signal has been transmitted through the router in order to adjust the transmission time lag between the optical signal and the corresponding optical label signal by the controllers

Ion generation apparatus and thin film forming apparatus and ion source

A thin film forming apparatus comprising a plasma generating chamber into which is introduced a gas to generate plasma; a first target and a second target which are made of a material to be sputtered and are disposed in the vicinity of both end portions of interior of the plasma generating chamber, respectively, at least one of the first and second targets having the form of a cylinder; at least one power supply for applying a negative potential to the first and second targets; an electromagnet adapted to establish the magnetic field within the plasma generating chamber and inducing the magnetic flux leaving one of the first and second targets and entering the other; and a specimen chamber which incorporates therein a substrate holder and is communicated to one end of the plasma generating chamber on the side of the cylindrical target. High density plasma generated in the plasma generating chamber sputters the targets so that sputtered substances which constituted the targets are deposited over the surface of a substrate, thereby forming a thin film.

Thin film forming apparatus and ion source utilizing plasma sputtering

A thin film forming apparatus comprises a plasma generating chamber into which is introduced a gas to generate plasma therein; a microwave introduction window connected to the plasma generating chamber for introducing the microwave into the latter, a first target and a second target made of materials to be sputtered and disposed at both end portions of interior of the plasma generating chamber, respectively, at least one of the first and second targets being in the form of a tube, at least one power supply for applying a negative voltage to the first and second targets, magnetic field producing means for producing the magnetic field and the magnetic flux leaving one of the first and second targets and entering the other, and a specimen chamber communicated to the plasma generating chamber and having a substrate holder installed therein. High-density ECR plasma generated within the plasma generating chamber sputters the targets so that the sputtered target materials are deposited on a substrate to form a thin film. It is also possible to extract ions in plasma by incorporating an ion extraction mechanism at the lower end of the plasma generating chamber.

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Atsugi, Japan

Morito Matsuoka