Fujitsu Optical Components Limited

Fujitsu Corporation

Tdk Corporation

Yoshihiko Yoshida

Yoshinobu Kubota

Masaharu Doi

Yasuhiro Ohmori

Shintaro Takeuchi

Shuntaro Makino

Masaki Sugiyama

Shinji Maruyama

Teruo Kurahashi

Yoshihiro Takahashi

Nobuaki Mitamura

Toyokazu Sasaki

Kenji Sasaki

Akira Ishii

Shinji Iwatsuka

Takehito Tanaka

Hiroki Hara

Yasuhiro Omori

Tomoyuki Ito

Tomoyuki Itou

Yoshitada Kawashima

An optical device includes a silicon substrate, a waveguide formed of a thin film that is laminated on the silicon substrate and that is made of a perovskite oxide with a large electro-optic effect as compared to lithium niobate, and a cladding layer that covers the waveguide. Further, the optical device includes ground electrode that has a ground potential and a signal electrode that is arranged at a position facing the ground electrode and that applies driving voltage to the waveguide.

Optical device and optical communication apparatus

An optical device includes an X-cut substrate, and a first waveguide and a second waveguide each being formed on the substrate and having a folding structure. The optical device includes a first signal electrode to generate a first electric field, and a second signal electrode to generate a second electric field with a reverse phase as compared to the first field. The first waveguide includes a first waveguide on an outward side to which the first field is applied from the first signal electrode, and a first waveguide on a return side to which the second field is applied from the second signal electrode. The second waveguide includes a second waveguide on the outward side to which the first field is applied from the first signal electrode, and a second waveguide on the return side to which the second field is applied from the second signal electrode.

An optical device includes a substrate, a first cladding layer that is laminated on one surface of the substrate, and a first optical waveguide that is formed in the first cladding layer at a side opposite to the substrate in the first cladding layer. The optical device further includes an electro-optic crystal layer that is laminated on a surface of the first cladding layer at a side opposite to the substrate, and a second optical waveguide that is formed of the electro-optic crystal layer on a surface of the electro-optic crystal layer at a side opposite to the first cladding layer. The optical device further includes a second cladding layer that is laminated on a surface of the electro-optic crystal layer at a side opposite to the first cladding layer.

Optical device having dual waveguides with one being an electro-optic crystal waveguide

An optical device includes a thin film Lithium Niobate (LN) layer, a first optical waveguide, and a second optical waveguide. The thin film LN layer is an X-cut or a Y-cut LN layer. The first optical waveguide is an optical waveguide that is formed on the thin film LN layer along a direction that is substantially perpendicular to a Z direction of a crystal axis of the thin film LN layer. The second optical waveguide is an optical waveguide that is routed and connected to the first optical waveguide. At least a part of a core of the first optical waveguide is made thicker than a core of the second optical waveguide.

An electro-optic device is provided with a substrate, an optical waveguide formed of a lithium niobate film with a ridge shape on the substrate, and an electrode that applies an electric field to the optical waveguide. The optical waveguide includes a first waveguide section provided at least in an electric field application region applied with the electric field and having a thickness of 1 &#x3bc;m or larger and a second waveguide section provided in a region other than the electric field application region and having a thickness of 0.3 &#x3bc;m or larger and less than 1 &#x3bc;m.

Electro-optic device

An optical modulator includes an optical waveguide of a ridge type formed of a thin film of a dielectric material having an electro-optic effect over a substrate, a buffer layer covering the optical waveguide, and a signal electrode provided over the optical waveguide via the buffer layer, wherein a width of the signal electrode is greater than a ridge width of the optical waveguide and wherein the signal electrode covers at least one of sidewalls of a ridge of the optical waveguide.

Optical modulator, optical modulator module, and optical transmitter module

An optical modulator includes a substrate and an optical waveguide group. The optical waveguide group includes a pair of relay optical waveguides, a pair of first Mach-Zehnder type optical waveguides, and a pair of second Mach-Zehnder type optical waveguides. The pair of the first Mach-Zehnder type optical waveguides are connected to the pair of the relay optical waveguides and includes input ends arranged at positions that deviate from each other in a longitudinal direction of the substrate. The pair of the second Mach-Zehnder type optical waveguides are provided on a pair of branched waveguides of each of the first Mach-Zehnder type optical waveguides and includes input ends arranged at symmetric positions with respect to a straight line that passes through an input end serving as a branch point of the branched waveguides and that extends in the longitudinal direction of the substrate.

Optical modulator

An optical modulator includes a substrate having an electro-optic effect; a waveguide pattern provided on the substrate and configured to modulate light; and a dummy pattern having a predetermined potential along the waveguide pattern from an input side to an output side.

Optical modulator and optical module

An optical modulator includes: a ferroelectric substrate in which an input optical waveguide, a pair of branched optical waveguides, and an output optical waveguide are formed; a signal electrode that is formed in a vicinity of at least one of the pair of branched optical waveguides; a first protection member that is attached to an input end of the ferroelectric substrate in which the input optical waveguide is formed; and a second protection member that is attached to an output end of the ferroelectric substrate in which the output optical waveguide is formed. The first protection member and the second protection member have a Mohs hardness that is less than or equal to a Mohs hardness of the ferroelectric substrate, and are formed of a glass material that does not have a pyroelectric effect.

Optical modulator that is formed using ferroelectric substrate

An optical device includes a substrate having an electrooptical effect, and including an optical waveguide that guides light and a reflection groove having a bottom face that reflects light output from the optical waveguide; and a light-receiving element positioned above the reflection groove and fixed to the substrate. The light output from the optical waveguide into the reflection groove is reflected by the bottom face of the reflection groove while traveling through a space inside the reflection groove and is incident to the light-receiving element.

Optical device and fabrication method of optical device

A mach-zehnder optical modulator includes a substrate having electrooptical effect, wherein: the substrate has an inputting waveguide portion, two intermediate waveguide portions, an outputting waveguide portion and a sub optical waveguide portion, the inputting waveguide portion being branched and coupled to the two intermediate waveguide portions, the two intermediate waveguide portions being combined and coupled to the outputting waveguide portion, the sub optical waveguide being provided on at least one side of the outputting optical waveguide portion and having a given distance from the outputting optical waveguide portion, the sub optical waveguide portion guiding an off-light emitted from a combining portion of the two intermediate waveguide portions; and a width of a starting point of the sub optical waveguide portion is larger than the outputting waveguide portion.

Mach-zehnder modulator

There is provided an optical device including a plurality of Mach-Zehnder modulators; and an input branching waveguide to split an input light so as to direct the resulting light to the plurality of Mach-Zehnder modulators; the Mach-Zehnder modulator comprising: a splitter coupled to the input branching waveguide; pair of waveguides coupled to the splitter; a combiner coupled to the pair of waveguides; and a signal electrode to apply signals to the pair of waveguides; wherein the splitters are disposed in a different orientation to each other.

Optical device having a plurality of Mach-Zehnder modulators

An optical device guides propagating light to exit from a desired side surface of a substrate while maintaining sufficient power within a limited size of the substrate and which facilitates adjustment of a mount position of a light-receiving element by increasing allowable tolerance of the mount position of the light-receiving element. The optical device has a substrate, a light propagating direction path formed in the substrate, and a reflection groove formed in an output-side of said light propagating direction path in the substrate. A side wall of the reflection groove is formed to become a convex reflection surface in relation to light which enters from the light propagating direction path, and the light output from the light propagating direction path undergoes total reflection on a side wall forming the reflection surface and lets the reflected light exit from a predetermined side surface of the substrate while enlarging an image.

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Sapporo, Japan

Yoshihiko Yoshida