Nippon Telegraph and Telephone Corporation

Yusuke Muranaka

Toshikazu Hashimoto

Kota Shikama

Ai Yanagihara

Hidetaka Nishi

Tatsushi Nakahara

Shinji Matsuo

Shuichiro Asakawa

Nobuhiro Nunoya

Yohei Sakamaki

A low-loss optical switch device with a smaller number of ports for an optical switch in a network and node device capable of transmitting OCS-type and OPS-type optical signals is provided. The optical switch device includes: a high-speed add/drop optical switch composed of a plurality of optical switches, the optical switch having an optical waveguide structure made of a material whose refractive index or absorption coefficient changes on the order of nanoseconds, and the optical switch changing the refractive index or the absorption coefficient to perform switching of both OCS optical signals, which are optical-circuit-switching-type optical signals, and OPS optical signals, which are optical-packet-switching-type optical signals; and a plurality of circulators connected to an input port and an output port of the high-speed add/drop optical switch.

Optical switching apparatus

An optical switch is provided which is capable of driving control by the same FPGA and the same driving circuit configuration, and hence is capable of driving at a high speed and a low consumption power. The optical switch of the present disclosure is a 1×N optical switch having a structure in which with respect to an optical switch, a driving circuit of the optical switch is integrated in the vicinity of a control electrode of the optical switch. The optical switch includes a plurality of 2×2 optical switches and N optical gates. Different bias voltages (V) are set between the optical switches and the optical gates, and a driver for the 2×2 optical switch of the driving circuit and a driver for the optical gate are of the same circuit form.

1 x N optical switch

A wavelength tunable laser includes a filter region having a wavelength selection function on light from a gain region, wherein the filter region is a Sagnac interferometer and includes two ring resonators. The ring resonator has two optical couplers, and first and second curved waveguides connecting the two optical couplers, each of the two optical couplers is configured to receive input of the light from the gain region through an input-output port, to couple light of a resonant peak to a bar port of the input-output port, and to couple light except light at a resonant peak wavelength to a cross port of the input-output port, and the first curved waveguide connects the bar ports of the input-output ports of the two optical couplers, and the second curved waveguide connects the cross ports of ports, of two optical couplers, that the first curved waveguide is connected to.

Tunable laser

A wavelength tunable laser includes a filter region having a wavelength selection function on light from a gain region, wherein the filter region is a Sagnac interferometer and includes two ring resonators. The ring resonator has two optical couplers, and first and second curved waveguides connecting the two optical couplers, each of the two optical couplers is configured to receive input of the light from the gain region through an input-output port, to couple light of a resonant peak to a bar port of the input-output port, and to couple light except light at a resonant peak wavelength to a cross port of the input-output port, and each of radiation waveguides connected to the cross ports of the input-output ports of the two optical couplers has a structure that radiates the light except the light at the resonant peak wavelength to a front surface or a back surface of a substrate.

An optical switch includes 2-input 2-output optical switches connected in a multistage, an optical gate provided at each of N-th optical output ports, a driving circuit for operating the 2-input 2-output optical switch, and a driving circuit for operating the optical gate. The driving circuits for operating the 2-input 2-output optical switches are integrated in the vicinity of a control electrode on a waveguide of the 2-input 2-output optical switch. The driving circuits for operating the optical gates are integrated in the vicinity of a control electrode on a waveguide of the optical gates. The waveguide of the 2-input 2-output optical switch and the waveguide of the optical gate each has a p layer, an i layer, and an n layer sequentially formed on a semi-insulating substrate. The optical switch has a trench reaching the semi-insulating substrate between the 2-input 2-output optical switch and the optical gate.

Optical switch

Optical alignment between an optical waveguide device and an optical connection part is realized easily and at low cost. An optical circuit in which optical waveguides to be connected to optical fibers are formed includes: an alignment optical waveguide configured to be opposed to, on an optical waveguide edge face to which an optical connection part having guide holes for insertion of core wires of the optical fibers is to be fixed, a guide hole into which an alignment optical fiber is to be inserted; and a light path changing member configured to change a path of light to a vertical direction with respect to the optical axis direction of the core of the alignment optical waveguide.

Optical circuit and optical connection structure

There is provided an optical connection structure in which an optical fiber and an optical semiconductor waveguide are easily connected with low loss. The present invention relates to an optical connection structure configured to connect an optical waveguide device and an optical fiber including cores having different refractive indexes, wherein an optical connection component using a planar lightwave circuit is bonded and fixed on an end surface of an input/output waveguide of the optical waveguide device, a value of a refractive index of a core of the planar lightwave circuit is between a value of the refractive index of the core of the optical waveguide device and a value of the refractive index of the core of the optical fiber, and the optical waveguide device and the optical fiber are optically connected via the planar lightwave circuit.

Optical connection structure

Provided is an optical switch element capable of adjusting an output strength of light output from an optical switch to a fixed level. The optical switch element includes: an optical coupler configured to divide an input light into N fractions of light and output the N fractions of light, where N represents an integer equal to or larger than 2; N branch optical waveguides connected to an output side of the optical coupler; N light absorption gates connected to the respective N branch optical waveguides; and N output optical waveguides connected to the respective N light absorption gates, the optical coupler, the N branch optical waveguides, the N light absorption gates, and the N output optical waveguides being connected to one another in order, the N light absorption gates each being controlled to adjust an output strength of transmitted light output from the N output optical waveguides based on a loss amount acquired in advance by a light absorption effect or light amplification effect of the N light absorption gates.

Optical switch element

A node device capable of optimal transfer in accordance with the traffic situation of a network irrespective of the optical signaling system is provided. The node device includes a first wavelength selective switch connected to an input-side optical fiber; a fast selective switch connected to the first wavelength selective switch for cut-through or selective switching to an OCS controller or an OFS/OPS controller; an optical coupler connected to a cut-through output of the fast selective switch, an output of the OCS controller, and an output of the OFS/OPS controller; a second wavelength selective switch connected to an output of the optical coupler; and a node controller that performs wavelength assignment control for the first and second wavelength selective switches, path/label switch control for the fast selective switch, and flow/packet switch control for the OFS/OPS controller.

Node apparatus

Provided is an optical fiber connection component in which an optical waveguide of a planar lightwave circuit and an optical fiber can be connected after a process using SMT and reflow mounting technology. The optical fiber connection component includes: a plurality of fiber guide holes into which optical fibers are insertable at intervals equal to intervals of a plurality of optical waveguides of the planar lightwave circuit; and grooves for demarcating an area provided with the plurality of fiber guide holes and an area coated with an adhesive in an end surface to be joined with the planar lightwave circuit. The plurality of optical waveguides and the plurality of fiber guide holes are respectively aligned and fixed to the planar lightwave circuit with the adhesive in advance.

Optical fiber connection component and optical device manufacturing method

An optical fiber guide part fixes optical fibers optically connected to optical waveguides of an optical waveguide device and is adhesively fixed to the optical waveguide device. The optical fiber guide part includes a V-grooved substrate, in a surface of which plural V-grooves are formed in parallel to one another, a lid member fixed to a top of the V-grooved substrate such that the V-grooves are exposed in a neighborhood of at least that end face of the V-grooved substrate which is on a side of the optical waveguide device, and a lid member fixed to an exposed part of the V-grooves of the V-grooved substrate, pressing, from above, the optical fibers inserted in guide holes formed by the V-grooves and the lid member placed on the V-grooves.

Optical fiber guide component, optical connection structure and method for producing same

An optical module according to the present invention includes: a first plasmonic waveguide having one end formed of a first metal layer formed over an end portion of a first substrate, and having another end connected to one end of a first optical waveguide; a second metal layer that is formed on a side surface continuous with the end portion of the first substrate and formed to be continuous with the first metal layer; a second substrate provided with a second plasmonic waveguide formed of a third metal layer; and a second optical waveguide that is connected to the second plasmonic waveguide and formed on the second substrate, wherein the second metal layer and a part of the third metal layer are joined together to connect the first substrate to the second substrate.

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Tokyo, Japan

Yusuke Muranaka