Fujitsu Corporation

Haruhiko Tabuchi

Terukazu Naruse

Koji Terada

Kohei Shibata

Goji Nakagawa

Kazuhiro Tanaka

Shouichi Ogita

Takuya Fujii

Hirohiko Kobayashi

Haruhisa Soda

Mitsuru Ekawa

Nirou Okazaki

Masami Goto

Masumi Norizuki

Tsuyoshi Yamamoto

Seimi Sasaki

Kazunori Miura

Yuji Kotaki

Tsugio Kumai

Youske Yamazaki

Hirohide Kurakake

Yousuke Yamazaki

In order to prevent a spectrum of a wavelength channel from becoming narrower, a device according to the present invention includes a light dividing section capable of dividing a wavelength spectrum in an input light beam and outputting a plurality of divided light beams, which are spatially separated and have wavelength spectrum portions different from each other, and a wavelength-to-special-position-converter capable of spatially multiplexing the wavelength spectrum portions of the plurality of divided light beams from the light dividing section.

Optical device and light control method

An optical device enabling reducing device scale is constituted by M circulators (), (M being a natural number), a waveguide-type diffraction grating () including M first input/output waveguides () formed at its one end and M&#xd7;N second input/output waveguides (-to-N and-to-N) formed at the other end, (N being a natural number), and paths from the M circulators being connected to the M first input/output waveguides; and N reflection-type optical switches (-to-N) each for reflecting the optical paths for M adjacent waveguides out of the M&#xd7;N second input/output waveguides(-to-N and-to-N) and for switching over the returning-destination waveguide respectively, wherein the M circulators, the waveguide-type diffraction grating and N reflection-type optical switches are arranged in cascade. Consequently, the optical device can function preferably also as a wavelength selective optical switch available in a WDM transmission system.

Wavelength selective and level adjusting optical device

An optical device used, for example, in an add/drop multiplexer, a dynamic gain equalizer or a optical power monitor. The optical device includes (a) a substrate; (b) a first slab waveguide formed on the substrate; (c) channel waveguides of differing lengths formed on the substrate, light output from the first slab waveguide being input to the channel waveguides; and (d) a second slab waveguide formed on the substrate, light output from the channel waveguides being input to the second slab waveguide. An end face of the second slab waveguide shares a face with an end face of the substrate. The optical device has low loss characteristics.

Optical device with slab waveguide and channel waveguides on substrate

In order to enable coupling two multi-mode optical fibers with relatively high efficiencies while increasing the distance between lenses to be interposed as compared with the prior arts, with a device according to the present invention, a first condenser lens and a second condenser lens are arranged such that they are spaced apart from each other by four times the focal length and their optical center axes are coincident with each other. A first (second) multi-mode optical fiber is arranged such that it is spaced apart from the first (second) condenser lens by a distance larger than the focal length and the center axis of light emitted from the first (second) multi-mode optical fiber is substantially coincident with the optical center axis of the first (second) condenser lens.

Optical fiber device, optical monitor and optical switch

The present invention relates to an optical switching device capable of reducing the number of members such as a movable mirror for reflecting light beams to a relatively small number and suppressing the deterioration of the yield. The optical switching device is configured so as to include an input light deflection section capable of outputting a light beam as a deflected light beam at a plurality of different angles on the same plane, a collimated light output section capable of outputting the deflected light beam from the input light deflection section as a collimated light beam having passed any one of optical axes in a relationship of parallel translation to each another in accordance with the angle, and an output direction-path guide section for guiding the collimated light beam from the collimated light output section to the output direction-path in accordance with the optical axis.

Optical switching device and optical member unit

An optical device enabling reducing device scale is constituted by M circulators (), (M being a natural number), a waveguide-type diffraction grating () including M first input/output waveguides () formed at its one end and M&#xd7;N second input/output waveguides (-to-N and-to-N) formed at the other end, (N being a natural number), and paths from the M circulators being connected to the M first input/output waveguides; and N reflection-type optical switches (-to-N) each for reflecting the optical paths for M adjacent waveguides out of the M&#xd7;N second input/output waveguides (-to-N and-to-N) and for switching over the returning-destination waveguide respectively, wherein the M circulators, the waveguide-type diffraction grating and N reflection-type optical switches are arranged in cascade. Consequently, the optical device can function preferably also as a wavelength selective optical switch available in a WDM transmission system.

Optical device

An optical demultiplexing device used in an optical monitoring device includes an input port and an output port unit including a plurality of ports, and separates a WDM light of plural channels, which is input from the input port, for each wavelength to output to the output port unit. The output port unit includes a plurality of output port sets each of which includes at least two individual output ports as a set, and crosstalk between adjacent individual output ports in a single output port set is larger than crosstalk between adjacent individual output ports belonging to different output port sets.

Optical demultiplexing device and optical monitoring device

The invention provides a wavelength division demultiplexing apparatus which can reduce the connection loss between an input slab and channel waveguides and can suppress excitation of higher-order mode light to reduce the loss. The apparatus includes a first waveguide for propagating WDM light, a first slab for diffusing the light from the first waveguide, a plurality of channel waveguides having a series of different waveguide lengths with a predetermined difference for receiving and splitting the light from the first slab, a second slab for condensing the split light from the channel waveguides, and a second waveguide for propagating the light from the second slab therein, all formed on asubtrate. The channel waveguides and the first slab are optically connected to each other at a number of nodes greater than the number of nodes at which the channel waveguides and the second slab are connected to each other.

Wavelength division demultiplexing apparatus

An optical switching device of which cost and size are smaller than the conventional is provided. In the optical switching device, a spectroscopy section in each of optical switches disposed being piled up to plural layers is integrally formed. And there are provided with a first light control element integrally formed on paths of light beams, which are outputted from each of the first ports in each of the optical switches disposed being piled up to plural layers and propagate in space, a second light control element integrally formed on paths of the light beams, which are outputted from the spectroscopy section and propagate in space, and a third light control element formed integrally with each of second ports at a position corresponding to the reflection direction by reflector on paths of the reflected beams passed through the spectroscopy section in each of the optical switches.

Optical switching device

The present invention has for its object to provide an optical device whose size is made small. In order to achieve this, according to the present invention there is provided an optical device in which a clad and a core whose refractive index is relatively higher than that of the clad are formed on a substrate and light can be transmitted through the core, wherein the core is provided with an input light transmitting pattern section, a diffraction pattern section, and a phase difference generating pattern section. Further, at least in the phase difference generating pattern section, a part, where refractive indexes are different respectively in the direction parallel to the substrate and in the direction perpendicular to the substrate, is provided.

Optical device, polarization monitor and optical switch

In an arrayed waveguide grating type wavelength division demultiplexer including an input waveguide, an input slab waveguide, a phase-grating waveguide array composed of a plurality of optical channel waveguides, an output slab waveguide, and a plurality of output waveguides provided in a core layer so as to form a predetermined pattern, the input slab waveguide is configured to have portions with locally varied thickness in at least the core layer or the cladding layer at the vicinity of each coupling portion of the optical channel waveguide depending on the layout of the optical channel waveguides, whereby the input slab waveguide is made to have a high refractive index region having a refractive index relatively higher than surrounding regions thereof. With this arrangement of the device, the device can be applied to a case where it is undesirable to dope materials of Ge, Ti and Ce. Moreover, with this arrangement of the device, it becomes possible to avoid deterioration with time passage and reduce polarization dependent loss, thereby to improve optical coupling loss.

Arrayed waveguide grating type wavelength division demultiplexer

The present invention aims at providing a wavelength multiplexing/demultiplexing apparatus for reducing a loss at a portion where an input slab and channel waveguides are connected with each other, thereby capable of realizing the reduction of loss in the overall apparatus. In order to achieve the above object, in this wavelength multiplexing/demultiplexing apparatus comprising an input waveguide, an input slab, channel waveguides, an output slab and output waveguides that are formed on a substrate, a curvature radius (r1) of an output side circular arc interface of the input slab is smaller than a curvature radius (r2) of an input side circular arc interface of the output slab, and spacing (P ) between the channel waveguides at a portion where the input slab and each of the channel waveguides are connected with each other is smaller than spacing (P ) between the channel waveguides at a portion where each of the channel waveguides and the output slab are connected with each other.

Wavelength multiplexing/demultiplexing apparatus

The invention provides a wavelength division demultiplexing apparatus which can reduce the connection loss between an input slab and channel waveguides and can suppress excitation of higher-order mode light to reduce the loss. The apparatus includes a first waveguide for propagating WDM light, a first slab for diffusing the light from the first waveguide, a plurality of channel waveguides having a series of different waveguide lengths with a predetermined difference for receiving and splitting the light from the first slab, a second slab for condensing the split light from the channel waveguides, and a second waveguide for propagating the light from the second slab therein, all formed on a subtrate. The channel waveguides and the first slab are optically connected to each other at a number of nodes greater than the number of nodes at which the channel waveguides and the second slab are connected to each other.

A channel core pattern includes a plurality of core pattern elements having different lengths, another core pattern connected with the channel core pattern in series, and a refractive index of the channel core pattern is higher than a refractive index of the another core pattern.

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Kawasaki, Japan

Haruhiko Tabuchi