Patents Assigned to Fujitsu Optical Components Limited
  • Publication number: 20210318588
    Abstract: An optical modulator includes an optical waveguide, a first slab and a second slab. The optical waveguide is formed by filling polymer in a slot portion formed between a first rail and a second rail disposed in parallel to the first rail. The first slab includes a first partial slab electrically connected to a first electrode and a second partial slab that electrically connects the first rail and the first partial slab. In the first slab, a thickness dimension of the second partial slab is set small compared with that of the first rail. The second slab includes a third partial slab electrically connected to a second electrode and a fourth partial slab that electrically connects the second rail and the third partial slab. In the second slab, a thickness dimension of the fourth partial slab is set small compared with that of the second rail.
    Type: Application
    Filed: January 26, 2021
    Publication date: October 14, 2021
    Applicant: Fujitsu Optical Components Limited
    Inventors: Kazuyuki WAKABAYASHI, Tamotsu AKASHI, Toshihiro OHTANI
  • Patent number: 11143889
    Abstract: An optical transmission device includes: a substrate; a waveguide that is provided in the substrate and transmits an optical signal; a signal wiring that is provided in the substrate and transmits an electric signal; and a silicon wiring that is provided in the substrate and is silicon added with an impurity. The signal wiring is placed in an area of the substrate, the area being away from an end of the substrate by a predetermined distance or more. One end of the silicon substrate is connected to the signal wiring, and the other end of the silicon wiring extends to the end of the substrate.
    Type: Grant
    Filed: April 14, 2020
    Date of Patent: October 12, 2021
    Assignee: FUJITSU OPTICAL COMPONENTS LIMITED
    Inventor: Masaki Sugiyama
  • Publication number: 20210305976
    Abstract: An equalizer has a first tapped delay line in which N taps (N is a positive integer) are connected in cascade, a second tapped delay line having one tap and connected in parallel with the first tapped delay line, a first multiplier configured to multiply signals extracted from the N taps by corresponding coefficients, a second multiplier configured to multiply a signal output from the second tapped delay line by a second coefficient, and an adder configured to add products of the first multiplier and a product of the second multiplier. The first tapped delay line has a fixed delay, and the second tapped delay line has a variable delay changeable at a 1/M resolution of the fixed delay, where M is a number greater than 1.
    Type: Application
    Filed: February 3, 2021
    Publication date: September 30, 2021
    Applicant: Fujitsu Optical Components Limited
    Inventor: TOSHIO ISHII
  • Publication number: 20210294038
    Abstract: A 90-degree optical hybrid includes two optical splitters that respectively split inputted light into two beams, two optical combiners that respectively combine two beams of inputted light and thereby output two beams of interfering light respectively, and four arm waveguides that input light splitted by any of the two optical splitters into any of the two optical combiners. Each of the four arm waveguides has a bend waveguide arranged at its center and a plurality of optical waveguides including a tapered waveguide having a width that decreases toward the bend waveguide. Both ends of each of the plurality of optical waveguides are respectively in contact with a end surface of any one of the two optical splitter, the two optical combiners, the bend waveguide and the other of the plurality of optical waveguides, and each of the plurality of waveguides is the tapered waveguide or a linear waveguide.
    Type: Application
    Filed: February 18, 2021
    Publication date: September 23, 2021
    Applicant: Fujitsu Optical Components Limited
    Inventor: Akira OKA
  • Publication number: 20210278614
    Abstract: An optical module includes: a board that is accommodated in a housing and in which a through hole is formed; a metal plate that is bonded to an area of the board including the through hole; a component that is mounted on one surface of the metal plate and is arranged inside the through hole; and a thermal-conductive member that is arranged on another surface of the metal plate and transmits heat generated by the component to the housing.
    Type: Application
    Filed: December 23, 2020
    Publication date: September 9, 2021
    Applicant: Fujitsu Optical Components Limited
    Inventors: TERUHIRO KUBO, YUKA OJIMA, Tetsuo Ishizaka, Tomoyuki Ito
  • Publication number: 20210278597
    Abstract: An optical device includes: a substrate; an optical waveguide that forms a Mach-Zehnder interferometer; a signal electrode; and a ground electrode. The optical waveguide is placed between the signal electrode and the ground electrode. An electric field is generated in a direction along a surface of the substrate when a voltage is applied between the signal electrode and the ground electrode. The optical waveguide includes a first waveguide through which input light propagates, a curved waveguide which is optically coupled to the first waveguide, and a second waveguide which is optically coupled to the curved waveguide. The signal electrode includes first and second electrodes that are respectively placed near the first and second waveguides. An electric signal is supplied to the first electrode, and an inverted electric signal is supplied to the second electrode.
    Type: Application
    Filed: January 5, 2021
    Publication date: September 9, 2021
    Applicant: Fujitsu Optical Components Limited
    Inventor: Masaki SUGIYAMA
  • Patent number: 11112625
    Abstract: An optical transmission device has a modulator, a first terminal groove, and relay groove. The modulator has a groove on a waveguide formed on a substrate. EO polymer is placed in the groove in the modulator. The modulator modulates light propagated through the waveguide by changing the phase of the light propagated through the waveguide through change of the refractive index of the EO polymer placed in the groove in the modulator by means of an electric signal. The first terminal groove is formed on the substrate and has a width larger than a width of the groove in the modulator. The relay groove is formed on the substrate and communicates with the groove in the modulator and the first terminal groove. Furthermore, the EO polymer is placed in the relay groove and the first terminal groove.
    Type: Grant
    Filed: July 8, 2020
    Date of Patent: September 7, 2021
    Assignee: FUJITSU OPTICAL COMPONENTS LIMITED
    Inventors: Masaki Sugiyama, Tamotsu Akashi
  • Publication number: 20210270698
    Abstract: An optical device cut from a wafer into a chip by dicing, on the wafer, the optical device includes a plurality of optical waveguides; an optical circuit connected to the optical waveguide; and of the plurality of optical waveguides, a testing optical waveguide that guides test light to the optical circuit to be tested, by bypassing a non-connected optical waveguide portion at a terrace for mounting an optical chip component.
    Type: Application
    Filed: December 28, 2020
    Publication date: September 2, 2021
    Applicant: Fujitsu Optical Components Limited
    Inventor: Masaki SUGIYAMA
  • Publication number: 20210270697
    Abstract: An optical device includes an optical circuit and a test circuit optically connected to the optical circuit. The test circuit includes a first grating coupler configured to receive test light, a second grating coupler configured to output, as reference light, the test light passed through the first grating coupler, and a first branch coupler connected to an output of the first grating coupler. The first branch coupler includes first output connected to an input of the optical circuit and configured to branch and output the test light from the first grating coupler to the optical circuit. Further, the first branch coupler includes a second output connected to an input of the second grating coupler and configured to branch and output the test light from the first grating coupler to the second grating coupler.
    Type: Application
    Filed: December 21, 2020
    Publication date: September 2, 2021
    Applicant: Fujitsu Optical Components Limited
    Inventor: Masaki SUGIYAMA
  • Publication number: 20210273730
    Abstract: An optical circuit device includes a first to fourth optical couplers, wherein the first optical coupler splits a first input light into a first output beam and a second output beam with a 90-degree phase: difference therebetween, and the second optical coupler splits a second input light into a third output beam and a fourth output beam with a 180-degree phase difference therebetween. The third optical coupler combines one of the first and second output beams and one of the third and fourth output beams, and outputs a first optical signal and a second optical signal having a 180-degree phase shift from each other. The fourth optical coupler combines the other of the first and second output beams and the other of the third and fourth output beams, and outputs a third optical signal and a fourth optical signal having a 180-degree phase shift from each other.
    Type: Application
    Filed: January 7, 2021
    Publication date: September 2, 2021
    Applicant: Fujitsu Optical Components Limited
    Inventor: Akira OKA
  • Publication number: 20210273737
    Abstract: A light source device includes: a plurality of light sources that generate rays of light with different wavelengths corresponding to a plurality of target wavelengths located on a designated wavelength grid; a plurality of photodetectors that detect output powers of the plurality of light sources; a plurality of optical bandpass filters that are provided between the plurality of light sources and the plurality of photodetectors; a temperature adjustment unit that adjusts a temperature of an area around the plurality of light sources; and a processor that controls the temperature adjustment unit based on output signals of the plurality of photodetectors. Widths of passbands of the optical bandpass filters are less than a wavelength spacing in the wavelength grid.
    Type: Application
    Filed: December 29, 2020
    Publication date: September 2, 2021
    Applicant: Fujitsu Optical Components Limited
    Inventor: Koji OTSUBO
  • Publication number: 20210266009
    Abstract: An optical communication apparatus includes a level detector, an FIR filter, and a adjustor. The level detector detects level information that discriminates a change in a multi-value level based on an input signal used in a multi-value amplitude modulation system. The FIR filter compensates a signal band of the input signal in accordance with tap coefficients of a plurality of multipliers. The adjustor corrects the tap coefficient of each of the multipliers included in the FIR filter based on the level information detected in the level detector.
    Type: Application
    Filed: February 1, 2021
    Publication date: August 26, 2021
    Applicant: Fujitsu Optical Components Limited
    Inventor: TOSHIO ISHII
  • Publication number: 20210263220
    Abstract: An optical device has a first photonic waveguide provided on a substrate, a second photonic waveguide provided on the substrate and extending side by side with the first photonic waveguide, and a looped waveguide continuously connecting the first photonic waveguide and the second photonic waveguide on the substrate, wherein a width of at least one of the first photonic waveguide or the second photonic waveguide varies continuously along an optical axis, between a first position located at a side opposite to the looped waveguide and a second position connected to the looped waveguide, and wherein cross sections of the first photonic waveguide and the second photonic waveguide are congruent at the second position, and are incongruent at the first position.
    Type: Application
    Filed: February 17, 2021
    Publication date: August 26, 2021
    Applicant: Fujitsu Optical Components Limited
    Inventor: Akira OKA
  • Publication number: 20210250099
    Abstract: Controller and control method are provided. In particular, a controller is disclosed as being configured to hold intensities of a monitor signal, which changes according to an output from a region in a device, before and after altering a state of a portion in the region and control the state of the portion based on a difference between the held intensities.
    Type: Application
    Filed: December 28, 2020
    Publication date: August 12, 2021
    Applicant: Fujitsu Optical Components Limited
    Inventors: Tetsuji YAMABANA, Tsuyoshi MORISHITA
  • Patent number: 11086149
    Abstract: 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 ?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 ?m or larger and less than 1 ?m.
    Type: Grant
    Filed: March 27, 2020
    Date of Patent: August 10, 2021
    Assignees: TDK CORPORATION, FUJITSU OPTICAL COMPONENTS LIMITED
    Inventors: Shinji Iwatsuka, Kenji Sasaki, Hiroki Hara, Yasuhiro Ohmori, Masaharu Doi, Shintaro Takeuchi, Yoshihiko Yoshida, Yoshinobu Kubota
  • Publication number: 20210149133
    Abstract: An optical module includes: a module body that is configured to be inserted into a cage, at an entrance of the cage an electromagnetic wave shielding terminal being provided, and has a groove formed on one surface thereof and configured to engage with a latch part formed on the cage; and an engagement release member including a body that is provided with a pull tab, the body being slidably attached to the module body and configured to slide in response to an external force, and an arm part that extends from the body along the groove, and slides with respect to the groove in conjunction with the sliding of the body and release the engagement in a state in which the electromagnetic wave shielding terminal is pressed. The module body has a concave part on a surface of the groove, the surface being in contact with the arm part.
    Type: Application
    Filed: October 9, 2020
    Publication date: May 20, 2021
    Applicant: FUJITSU OPTICAL COMPONENTS LIMITED
    Inventor: KAZUYUKI KURAMOCHI
  • Patent number: 11003044
    Abstract: An electro-optic device is provided with a Mach-Zehnder optical waveguide including at least one linear section and at least one curved section and a differential RF signal electrode provided along the Mach-Zehnder optical waveguide. Optical input/output ports of the Mach-Zehnder optical waveguide are provided at one end side in a first direction in which the linear section extends. The differential RF signal electrode is provided in both the linear and curved sections.
    Type: Grant
    Filed: February 24, 2020
    Date of Patent: May 11, 2021
    Assignees: TDK CORPORATION, FUJITSU OPTICAL COMPONENTS LIMITED
    Inventors: Hiroki Hara, Shinji Iwatsuka, Takashi Kikukawa, Toshinori Matsuura, Yasuhiro Ohmori, Masaharu Doi, Shintaro Takeuchi, Yoshinobu Kubota
  • Publication number: 20210135759
    Abstract: An optical transmission apparatus includes a modulation unit that generates modulated light by modulating light while bias on which a low-frequency signal is superimposed is applied thereto; an optical amplification unit that generates amplified light by amplifying the modulated light while holding an intensity of the amplified light at a changeable target value; an optical detection unit that generates an electric signal by performing photoelectric conversion on a part of the amplified light; an amplification unit that amplifies the electric signal while suppressing variation in the amplified electric signal, the variation being due to a change of the target value; and a control unit that detects a low-frequency component from the amplified electric signal the variation of which is suppressed and controls the bias on a basis of the detected low-frequency component, the low-frequency component being generated by the low-frequency signal.
    Type: Application
    Filed: October 22, 2020
    Publication date: May 6, 2021
    Applicant: FUJITSU OPTICAL COMPONENTS LIMITED
    Inventor: Iori SHIRAKAWA
  • Patent number: 10998974
    Abstract: An optical device is formed on an optical IC chip. The optical device includes: an optical device circuit; a first optical waveguide that is coupled to the a first grating coupler; a second grating coupler; a polarization rotator that is coupled to the first grating coupler; a polarization beam combiner or a polarization beam splitter that is coupled to the polarization rotator and to the second grating coupler; and a second optical waveguide that is coupled to the polarization beam combiner or to the polarization beam splitter. The first optical waveguide and the second optical waveguide respectively extend to an edge of the optical IC chip.
    Type: Grant
    Filed: July 8, 2019
    Date of Patent: May 4, 2021
    Assignee: FUJITSU OPTICAL COMPONENTS LIMITED
    Inventor: Masaki Sugiyama
  • Patent number: 10998978
    Abstract: An optical transmission apparatus includes a modulation unit that generates modulated light by modulating light while bias on which a low-frequency signal is superimposed is applied thereto; an optical amplification unit that generates amplified light by amplifying the modulated light while holding an intensity of the amplified light at a changeable target value; an optical detection unit that generates an electric signal by performing photoelectric conversion on a part of the amplified light; an amplification unit that amplifies the electric signal while suppressing variation in the amplified electric signal, the variation being due to a change of the target value; and a control unit that detects a low-frequency component from the amplified electric signal the variation of which is suppressed and controls the bias on a basis of the detected low-frequency component, the low-frequency component being generated by the low-frequency signal.
    Type: Grant
    Filed: October 22, 2020
    Date of Patent: May 4, 2021
    Assignee: FUJITSU OPTICAL COMPONENTS LIMITED
    Inventor: Iori Shirakawa