Phase Modulation Type Patents (Class 385/3)
  • Patent number: 8295655
    Abstract: An optical modulator includes a ring resonator with a waveguide adjacent to and optically coupled to the micro-ring resonator. A p-i-n junction is formed about the ring resonator. An optional additional doped region may be formed opposite the waveguide from the ring resonator and when combined with the p-i-n junction forms a nearly closed p-i-n junction about the ring resonator. The ring resonator may be a silicon micro-ring resonator. Multiple different resonant frequency resonators may be coupled to the waveguide along with different detectors to multiplex light on the waveguide. The spectrum of the resonator may be controlled by an applied voltage. A prepulsing device may be used to enhance electrical transitions to enhance the speed of the modulator.
    Type: Grant
    Filed: August 24, 2007
    Date of Patent: October 23, 2012
    Assignee: Cornell Research Foundation, Inc.
    Inventors: Sasikanth Manipatruni, Qianfan Xu, Michal Lipson
  • Publication number: 20120257850
    Abstract: A downsized, low-power electro-optical modulator that achieves reducing both of the additional resistance in the modulation portion and the optical loss each caused by electrodes at the same time is provided. The electro-optical modulator includes a rib waveguide formed by stacking a second semiconductor layer 9 having a different conductivity type from a first semiconductor layer 8 on the first semiconductor layer 8 via a dielectric film 11, and the semiconductor layers 8 and 9 are connectable to an external terminal via highly-doped portions 4 and 10, respectively. In a region in the vicinity of contact surfaces of the semiconductor layers 8 and 9 with the dielectric film 11, a free carrier is accumulated, removed, or inverted by an electrical signal from the external terminal, and whereby a concentration of the free carrier in an electric field region of an optical signal is modulated, so that a phase of the optical signal can be modulated.
    Type: Application
    Filed: June 8, 2010
    Publication date: October 11, 2012
    Applicant: NEC CORPORATION
    Inventors: Junichi Fujikata, Jun Ushida, Akio Toda, Motofumi Saitoh
  • Publication number: 20120251031
    Abstract: A system and method for cancellation of RF interference in the optical domain. The system and method utilize two Mach-Zehnder electrooptic modulators biased for parallel counter-phase modulation. The method of signal subtraction is referred to as incoherent optical subtraction, since two independent laser sources serve as the optical carrier waves. The system has produced the broadband cancellation result while simultaneously recovering a 50 dBm signal which was initially “buried” under the broadband interference. The cancellation depths achieved by the system are due to the accurate channel tracking and precise time delays attainable with modern optical devices—unattainable with state-of-the-art electronic devices at the time of this writing.
    Type: Application
    Filed: November 5, 2009
    Publication date: October 4, 2012
    Inventors: John Suarez, Konstantin Kravtsov, Paul R. Prucnal
  • Publication number: 20120251032
    Abstract: The present invention provides a compact, broad-band, and low-drive-voltage optical modulator module capable of generating any multilevel optical modulation. The optical modulator module according to an exemplary aspect of the present invention includes a digital segmented electrode structure optical modulator and m individual driving circuits. The digital segmented electrode structure optical modulator includes semiconductor optical waveguides and at least m waveguide-type optical phase modulator regions. An i-th individual driving circuit includes a driving circuit and a phase shift circuit. The driving circuit amplifies a digital input signal in synchronization with a clock signal and outputs the signal to an i-th waveguide-type optical phase modulator region. The phase shift circuit applies a delay to a signal branched from the clock signal. A j-th individual driving circuit receives an output signal from the phase shift circuit of a (j?1)-th individual driving circuit as a clock signal.
    Type: Application
    Filed: March 30, 2012
    Publication date: October 4, 2012
    Applicant: NEC Corporation
    Inventor: Tomoaki KATO
  • Patent number: 8280201
    Abstract: A Mach-Zehnder modulator has an optical splitting element splitting an input optical signal into two optical signals that are conveyed by two optical waveguide arms, and an optical combining element combining the two optical signals into an output optical signal. Two traveling wave electrodes (TWEs) carry an electrical modulation signal to induce a change in phase of these two optical signals, and include a number of pairs of modulation electrodes positioned adjacent to the waveguide arms. At least some of the electrodes in one waveguide arm have a different shape (e.g., length or width) than the electrodes in the other waveguide arm to alter the effectiveness of the electrodes in inducing a phase change in the two optical signals.
    Type: Grant
    Filed: December 8, 2009
    Date of Patent: October 2, 2012
    Assignee: COGO Oprtonics, Inc.
    Inventor: Kelvin Prosyk
  • Publication number: 20120243820
    Abstract: An optical demultiplexer has first and second input ports and first and second output ports. When optical signal is introduced into the first input port, intensity of optical signal output from the first output port is equal to that from the second output port. When optical signal is introduced into the second input port, intensity of optical signal output from the first output port is larger than that from the second output port. An optical multiplexer has third and fourth input ports and third and fourth output ports. A first optical waveguide connects between the first output port and the third input port, while a second optical waveguide connects between the second output port and the fourth input port. Voltages applied to a first modulation electrode and a second modulation electrode work to cause changes in the optical path lengths of the first optical waveguide and the second optical waveguide.
    Type: Application
    Filed: January 31, 2012
    Publication date: September 27, 2012
    Applicant: FUJITSU LIMITED
    Inventor: Akinori HAYAKAWA
  • Publication number: 20120237156
    Abstract: An optical modulator has a first branch and a second branch, both being connectable to an input, in particular to a light source. The first branch has an amplitude modulator and a phase shifter, and the amplitude modulator is operable by a first signal that is substantially sinusoidal. The second branch has an amplitude modulator that is operable by a second signal that is substantially 90 degree phase shifted to the first signal. A combining unit with two inputs and two outputs combines the optical fields of the first and second branches. Each output is arranged to supply an optical carrier. A combined optical modulator is formed with at least one such optical modulator. Further, there is provided a method for providing several optical carriers based on an input signal.
    Type: Application
    Filed: March 16, 2011
    Publication date: September 20, 2012
    Applicant: NOKIA SIEMENS NETWORKS OY
    Inventors: Harald Rohde, Erich Gottwald
  • Patent number: 8270778
    Abstract: A single-photon absorption all-optical signal-processing device, systems employing the same, and methods of making and using the same. Illustrative examples are provided based on silicon semiconductor technology that employs rectangular waveguides fabricated on SOI wafers. In some embodiments, it is observed that the waveguides have surface state density, ?, of not less than 1.5×1018 cm?1s?1mW?1 to provide a single-photon absorption operation mode. In some embodiments, some portion of the ridge waveguide structure has a surface to volume ratio of at least 18 ?m?1, computed using a unit length of 1 ?m of the waveguide, with the width and depth dimensions of the waveguide being measured in units of microns.
    Type: Grant
    Filed: August 6, 2010
    Date of Patent: September 18, 2012
    Assignee: University of Washington through its Center for Commercialization
    Inventors: Michael J. Hochberg, Thomas W. Baehr-Jones
  • Patent number: 8270780
    Abstract: It is an object of the present invention to provide an optical switch system using optical interference. An optical switch system (1) comprises an input part (2) of an optical signal, a branching part (3) of the signal, a main Mach-Zehnder waveguide (MZC) (7), a first intensity modulator (9) provided on a first arm (4) for controlling an amplitude of an optical signal propagating through the first arm (4), a second intensity modulator (10) provided on a second arm (5) for controlling an amplitude of an optical signal propagating through the second arm (5), and a combining part (6) of the signals outputted from the first arm and the second arm, wherein one or both of the branching part (3) and the combining part (6) are X-branched.
    Type: Grant
    Filed: November 29, 2006
    Date of Patent: September 18, 2012
    Assignee: National Institute of Information and Communications Technology
    Inventors: Tetsuya Kawanishi, Masayuki Izutsu, Takahide Sakamoto, Masahiro Tsuchiya
  • Publication number: 20120230627
    Abstract: An optical control element having a substrate 1 having an electro-optic effect, an optical waveguide 2 formed on the substrate, and a control electrode 3 that is provided on the substrate and controls the phase of light that propagates through the optical waveguide, in which the control electrode 3 has a plurality of resonant-type electrodes 31 and 32 that are disposed along the optical waveguide 2 and have different resonance frequencies (f1 and f2), an feeder electrode 30 through which control signals are input and branched signal electrodes that are branched from the feeder electrode are connected to the respective resonant-type electrodes, and the branched signal electrode is configured to match a timing at which the electric control signal is applied to each of the resonant-type electrodes and a timing at which the light that propagates through the optical waveguide passes at the section of each of the resonant-type electrodes.
    Type: Application
    Filed: March 8, 2012
    Publication date: September 13, 2012
    Applicant: Sumitomo Osaka Cement Co., Ltd.
    Inventors: Masayuki MOTOYA, Junichiro Ichikawa, Hiroshi Murata
  • Publication number: 20120230625
    Abstract: An optical modulator includes: a substrate made of a material having an electro-optical effect; an optical waveguide formed on the substrate; and a modulation electrode for modulating an optical wave propagating through the optical waveguide, wherein emitted light emitted from the optical waveguide is guided by optical fiber, and polarization of the substrate is reversed in a predetermined pattern along the optical waveguide so as to provide waveform distortion having a characteristic opposite to a wavelength dispersion characteristic of the optical fiber.
    Type: Application
    Filed: March 6, 2012
    Publication date: September 13, 2012
    Applicant: Sumitomo Osaka Cement Co., Ltd.
    Inventors: Junichiro ICHIKAWA, Satoshi OIKAWA, Hiroshi MURATA, Yasuyuki OZEKI
  • Publication number: 20120230626
    Abstract: An optical modulator is configured to include multiple modulating sections formed along each arm and create a unary-encoded optical output signal by driving the number of sections required to represent the data value being transmitted (e.g., three sections driven to represent the data value “3”, four sections driven to represent the data value “4”). An auxiliary modulating section, isolated from the optical signal path, is included for creating a path for current flow in situations where only an odd number of modulating sections are required to represent the data. The activation of the auxiliary modulation section minimizes the current imbalance that would otherwise be present along a common node of the arrangement.
    Type: Application
    Filed: March 7, 2012
    Publication date: September 13, 2012
    Applicant: LIGHTWIRE, INC.
    Inventors: Peter C. Metz, Bipin Dama, Kalpendu Shastri
  • Patent number: 8254009
    Abstract: An optically powered optical modulator comprises an optical modulation component, such as an electro-optical modulator, acousto-optic modulator or magneto-optic modulator, in combination with one or two lens assemblies positioned at one or both apertures of the optical modulation component, so that the optical modulator formed by the combination of the lens assembly or assemblies and the optical modulation component has optical focus power.
    Type: Grant
    Filed: February 2, 2011
    Date of Patent: August 28, 2012
    Assignee: PV Labs, Inc.
    Inventor: Eiji Yafuso
  • Patent number: 8254732
    Abstract: An optical modulator 100 includes an input unit 110, a splitter unit 120, a first waveguide 131, a second waveguide 132, a directional coupler unit 140, a first output unit 151, a second output unit 152, a first liquid-crystal cell 161, and a second liquid-crystal cell 162. The splitter unit 120, the first waveguide 131, the second waveguide 132, and the directional coupler unit 140 form an optical interferometer that branches an input light and causes the branched lights to interfere. The first liquid-crystal cell 161 and the second liquid-crystal cell 162 transmit the lights branched in the optical interferometer and delay the lights according to applied signals, respectively. The second liquid-crystal cell 162 is thinner than the first liquid-crystal cell 161.
    Type: Grant
    Filed: March 10, 2010
    Date of Patent: August 28, 2012
    Assignee: Citizen Holdings Co., Ltd.
    Inventors: Masafumi Ide, Takaaki Takeishi
  • Patent number: 8252670
    Abstract: The invention relates to a production method of a lateral electro-optical modulator on an SOI substrate, the modulator comprising a rib waveguide formed in the thin layer of silicon of the SOI substrate, the rib waveguide being placed between a doped region P and a doped region N formed in the thin layer of silicon, the rib waveguide occupying an intrinsic region of the thin layer, at least one doped zone P being formed in the rib and perpendicularly to the substrate. The method comprises masking steps of the thin layer of silicon to define therein the rib of the waveguide, etching of the rib, masking of the thin layer of silicon to delimit the parts to be doped P, doping of the parts to be doped P, masking of the thin layer of silicon to delimit the region to be doped N and doping of the region to be doped N.
    Type: Grant
    Filed: October 14, 2009
    Date of Patent: August 28, 2012
    Assignee: Commissariat a l'Energie Atomique
    Inventor: Jean-Marc Fedeli
  • Publication number: 20120212801
    Abstract: An optical system including a plurality of fibers each providing a fiber beam and at least one tapered fiber bundle. The tapered fiber bundle includes a plurality of input end fibers, a plurality of output end fibers and a center bundle portion, where each input end fiber is coupled to a separate one of the fibers, and where the bundle portion combines all of the fiber beams received by the input end fibers into a single combined beam and each output end fiber is capable of receiving the combined beam separately from the other output end fibers. The optical system also includes a plurality of optical output channels where each optical output channel is coupled to a separate one of the output end fibers.
    Type: Application
    Filed: April 30, 2012
    Publication date: August 23, 2012
    Applicant: Northrop Grumman Systems Corporation
    Inventor: JOSHUA ELLIOTT ROTHENBERG
  • Patent number: 8244077
    Abstract: This invention provides a versatile unit cell as well as programmable and reconfigurable optical signal processors (such as optical-domain RF filters) that are constructed from arrays of those unit cells interconnected by optical waveguides. Each unit cell comprises an optical microdisk, an optical phase shifter, and at least one input/output optical waveguide, wherein the microdisk and the phase shifter are both optically connected to a common waveguide.
    Type: Grant
    Filed: May 24, 2011
    Date of Patent: August 14, 2012
    Assignee: HRL Laboratories, LLC
    Inventor: Daniel Yap
  • Patent number: 8244075
    Abstract: There is provided an optical device including a substrate having an electro-optical effect, a plurality of optical modulators including bias electrodes to which a bias voltage is applied so as to generate an electric field from one of the bias electrodes to another of the bias electrodes, and the bias electrodes of the optical modulators being disposed above the substrate, and a partition conductor to reduce influence of the electric field from the bias electrode of a first optical modulator to an optical waveguide of a second optical modulator, the partition conductor being disposed above the substrate.
    Type: Grant
    Filed: July 16, 2010
    Date of Patent: August 14, 2012
    Assignee: Fujitsu Optical Components Limited
    Inventor: Masaki Sugiyama
  • Patent number: 8244076
    Abstract: A tuneable electro-optic modulator (1) comprising first and second spaced apart output optical waveguides (2, 3), each output optical waveguide comprising a coupled portion (12) optically coupled to a corresponding coupled portion (13) of the other output optical waveguide, the coupled portions defining a coupling region (14) therebetween; an optical source adapted to symmetrically provide an optical signal to the first and second output optical waveguides; a portion of each of the output optical waveguides having a signal electrode (6, 7) thereon; the modulator further comprising a central optical waveguide (15), at least a portion of which is arranged in the coupling region, the central optical waveguide having a tuning electrode (16) thereon.
    Type: Grant
    Filed: June 14, 2007
    Date of Patent: August 14, 2012
    Assignee: U2T Photonics UK Limited
    Inventor: John Heaton
  • Publication number: 20120201488
    Abstract: In an embodiment, a phase shifting device may be provided. The phase shifting device may include a supporting layer and a semiconducting layer disposed above the supporting layer. The semiconducting layer may include a first doped region doped with doping atoms of a first conductivity type and arranged on the supporting layer; and a second doped region doped with doping atoms of a second conductivity type being different from the first conductivity type; wherein the second doped region may be disposed over the first doped region such that a first doped regions junction may be formed in a direction substantially parallel to a surface of the supporting layer and a second doped regions junction may be formed in a direction substantially perpendicular to the surface of the supporting layer. A method of forming a phase shifting device and an electro-optic device may also be provided.
    Type: Application
    Filed: June 22, 2009
    Publication date: August 9, 2012
    Applicant: AGENCY FOR SCIENCE, TECHNOLOGY AND RESEARCH
    Inventors: Tsung-Yang Jason Liow, Guo Qiang Patrick Lo, Mingbin Yu, Qing Fang
  • Publication number: 20120195544
    Abstract: An optical interferometer for demodulating a differential phase shift keying optical signal includes a planar lightwave circuit and at least one free space delay line optically coupled to the planar lightwave circuit. The planar lightwave circuit has a waveguide splitter, a waveguide coupler, and a phase adjuster. In operation, the splitter splits the optical signal into equal portions, the phase adjuster adjusts the relative phase of the optical signal portions, and the free space delay line provides one-bit delay between the portions of the optical signal. The delayed signals are mixed in the waveguide coupler. The free space delay line can be made variable for adjustment of the bit delay for operation at different bit rates, and/or for optimization of the interferometer performance.
    Type: Application
    Filed: January 30, 2012
    Publication date: August 2, 2012
    Inventors: Jinxi Shen, Hiroaki Yamada, David J. Chapman, Shanrui Ren
  • Patent number: 8233752
    Abstract: An optical waveguide device includes a substrate of a ferroelectric material, at least a pair of electrodes 4A, 4B provided on one main face of the substrate, and a channel-type optical waveguide 5A formed in a gap 1 of the pair of the electrodes. The optical waveguide 5A has a curved part 15. A central line C of the gap 1 is provided outside of a center line WC of the optical waveguide with respect to the center O of curvature of the curved part 15.
    Type: Grant
    Filed: July 29, 2010
    Date of Patent: July 31, 2012
    Assignee: NGK Insulators, Ltd.
    Inventors: Akiyoshi Ide, Jungo Kondo, Osamu Mitomi, Yasunori Iwasaki, Kenji Aoki
  • Patent number: 8233753
    Abstract: An electric field sensor or a magnetic field sensor includes an optical fiber and an electro-optic layer or a magneto-optic layer. The electro-optic layer or a magneto-optic layer is provided on an end surface of an end portion of the optical fiber. The end surface of the optical fiber is a convex shape. The optical fiber may have the end portion with a shape of a substantial cone formed by extending the end portion, and the electro-optic layer or the magneto-optic layer may be formed on a side surface of a front end of the substantial cone. A dielectric layer may be further included between the optic layer and the end surface.
    Type: Grant
    Filed: June 23, 2006
    Date of Patent: July 31, 2012
    Assignee: NEC Corporation
    Inventors: Mizuki Iwanami, Masafumi Nakada, Norio Masuda, Keishi Ohashi
  • Patent number: 8229258
    Abstract: An optical waveguide-type wavelength domain switch includes a waveguide-type multi/demultiplexing device laminate comprising three or more laminated waveguide-type multi/demultiplexing devices, a lens system positioned on a demultiplex side of the waveguide-type multi/demultiplexing device laminate, and a reflective optical phase-modulating cell positioned on an opposite side of the waveguide-type multi/demultiplexing device laminate to the lens system.
    Type: Grant
    Filed: September 16, 2009
    Date of Patent: July 24, 2012
    Assignees: National Institute of Advanced Industrial Science and Technology, Hitachi Cable, Ltd., Keio University
    Inventors: Hiroshi Ishikawa, Toshifumi Hasama, Hitoshi Kawashima, Kenji Kintaka, Masahiko Mori, Hisato Uetsuka, Hiroyuki Tsuda, Keisuke Sorimoto
  • Patent number: 8213750
    Abstract: A laser system includes a multimode fiber (MMF) receiving a single-mode input beam and a mechanical oscillator coupled to the MMF. The oscillator is operative to modulate a phase of interference wave by periodically extending the fiber total length at such a frequency that a cross-coupling coefficient between fundamental and at least one high-order modes is substantially minimized.
    Type: Grant
    Filed: May 20, 2009
    Date of Patent: July 3, 2012
    Assignee: IPG Photonics Corporation
    Inventor: Roman Ygodkin
  • Patent number: 8213754
    Abstract: An optical splitter, a combiner and a device. The optical splitter comprises a first longitudinal waveguide for receiving an incoming light wave; at least first and second pairs of output waveguides, the output waveguides of each pair being disposed on opposite sides of the first waveguide; wherein each of the output waveguides of each pair comprises a longitudinal portion disposed parallel to the first waveguide and such that optical power is coupled from the first waveguide into the respective longitudinal portions and the longitudinal portions of output waveguides of the first and second pairs are displaced along a length of the first waveguide; wherein each of the output waveguides of each pair further comprises a substantially S-shaped portion continuing from the respective longitudinal portions and such that optical power coupling between the respective S-shaped portions of output waveguides of the first and second pairs is substantially inhibited.
    Type: Grant
    Filed: June 21, 2007
    Date of Patent: July 3, 2012
    Assignee: Agency for Science Technology and Research
    Inventors: Jason Png, Soon Thor Lim
  • Publication number: 20120163750
    Abstract: An optical polarization rotator includes first and second optical waveguide ribs located along a planar surface of a substrate. The second optical waveguide rib is located farther from the surface than the first optical waveguide rib. First segments of the optical waveguide ribs form a vertical stack over the substrate, and second segments of the optical waveguide ribs are offset laterally in a direction along the planar surface. The first and second optical waveguide ribs are formed of materials with different bulk refractive indexes.
    Type: Application
    Filed: December 22, 2010
    Publication date: June 28, 2012
    Inventor: Long Chen
  • Publication number: 20120163749
    Abstract: An integrated circuit is configured for optical communication via an optical polymer stack located on top of the integrated circuit. The optical polymer stack may include one or more electro-optic polymer devices including an electro-optic polymer. The electro-optic polymer may include a host polymer and a second order nonlinear chromomophore, the host polymer and the chromophore both including aryl groups configured to interact with one another to provide enhanced thermal and/or temporal stability.
    Type: Application
    Filed: December 8, 2010
    Publication date: June 28, 2012
    Applicant: GIGOPTIX, INC.
    Inventors: Diyun HUANG, Bing LI, Eric MILLER, Danliang JIN, Christopher A. WIKLOF, Guomin YU
  • Patent number: 8206042
    Abstract: A package design for electro-optic devices has been developed in which the substrate supporting the electro-optic element serves also as the base of the device housing. The electro-optic element is flip-chip bonded to the substrate. In a preferred embodiment the substrate is a multi-level wiring board.
    Type: Grant
    Filed: July 20, 2009
    Date of Patent: June 26, 2012
    Assignee: Oclaro (North America), Inc.
    Inventors: Roberto Galeotti, Luigi Gobbi, Mario Bonazzoli
  • Publication number: 20120155796
    Abstract: A phase modulator may include a middle layer having a first refractive index, a first surrounding layer of material in contact with the middle layer and having a second refractive index, a second surrounding layer of material in contact with the middle layer and may having a third refractive index, a first electrode in electrical contact with the first surrounding layer, and a second electrode may be in electrical contact with the second surrounding layer. When no voltage is applied across the first electrode and the second electrode, the first refractive index may be greater than the second refractive index and the third refractive index. When a voltage is applied across the first electrode and the second electrode, the first refractive index may be less than the second refractive index within a portion of the phase modulator substantially within an electric field induced by such voltage.
    Type: Application
    Filed: December 17, 2010
    Publication date: June 21, 2012
    Inventor: Alexander Umnov
  • Patent number: 8204347
    Abstract: In a conventional optical signal processing device, a confocal optical system is configured in which a focusing lens is positioned at a substantially-intermediate point of a free space optical path. Thus, the free space optical system had a long length. It has been difficult to reduce the size of the entire device. The optical signal processing device of the present invention uses a lens layout configuration different from the confocal optical system to thereby significantly reduce the length of the system. The optical signal processing device consists of the first focusing lens positioned in the close vicinity of a signal processing device, and the second focusing lens positioned in the vicinity of a dispersing element. A distance between the dispersing element and the signal processing device is approximately a focal length of the first focusing lens. Compared with the conventional technique, the length of the optical path can be halved.
    Type: Grant
    Filed: August 21, 2008
    Date of Patent: June 19, 2012
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Naoki Ooba, Kenya Suzuki, Motohaya Ishii, Shinji Mino, Atsushi Aratake
  • Patent number: 8200055
    Abstract: Methods and devices for optical beam steering are disclosed including coupling a laser light into an apparatus comprising a first substrate; an array of air core photonic crystal waveguides; columnar members etched around each air core waveguide; a pair of metal electrodes around the columnar members; a trench around the pair of metal electrodes surrounding each air core photonic crystal waveguide; a second substrate coupled to the first substrate comprising electrical interconnection lines; and a holographic fanout array comprising a third substrate; a photopolymer film coated on the third substrate; a hologram written in the photopolymer film configured to couple the laser light into the third substrate; and an array of holograms recorded in the photopolymer film configured to couple a portion of the laser light into the waveguides; and passing a current through the electrodes to induce a refractive index change in the first substrate to control the phase of the portion of the laser light that passes throug
    Type: Grant
    Filed: July 19, 2010
    Date of Patent: June 12, 2012
    Inventors: Harish Subbaraman, Ray T Chen
  • Publication number: 20120141062
    Abstract: Systems and methods for driving an optical modulator are provided. In one embodiment, a modulation drive circuit comprises: a balanced impedance network having a first and a second output generated from a first input, and a third and a fourth output generated from a second input, wherein the first and second outputs are balanced with one another, and the third and fourth outputs are balanced with one another; a first differential amplifier, wherein an inverting input of the first differential amplifier couples to the first output of the distribution network and a non-inverting input of the first differential amplifier couples to the third output of the distribution network; and a second differential amplifier, wherein an inverting input of the second differential amplifier couples to the fourth output of the distribution network and a non-inverting input of the second differential amplifier couples to the second output of the distribution network.
    Type: Application
    Filed: December 7, 2010
    Publication date: June 7, 2012
    Applicant: HONEYWELL INTERNATIONAL INC.
    Inventors: Douglas E. Smith, Steven G. Armstrong, Derek Mead
  • Publication number: 20120134620
    Abstract: A Mach-Zehnder optical modulator includes a join-and-branch portion, two light wave guides connected with the join-and-branch portion, two output light waveguides connected with the join-and-branch portion, arm electrodes respectively provided on the two light waveguides, light intensity detection electrodes respectively provided on the two output light waveguides, and a leakage suppression electrode provided between the arm electrodes and the light intensity detection electrodes.
    Type: Application
    Filed: November 30, 2011
    Publication date: May 31, 2012
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Kazuhiro Yamaji, Katsumi Uesaka
  • Publication number: 20120134619
    Abstract: An optical modulation apparatus including: a Mach-Zehnder optical modulator having two optical waveguides, two output optical waveguides and a join-and-branch portion; a phase adjustment circuit configured to output a phase control signal to phase adjustment electrodes provided respectively on the two optical waveguides; a drive circuit configured to output a modulation signal to modulation electrodes provided respectively on the two optical waveguides as a differential signal, the modulation signal modulating lights propagated in the two optical waveguides; and a signal polarity reversal circuit configured to reverse a polarity of the differential signal to be output from the drive circuit.
    Type: Application
    Filed: November 29, 2011
    Publication date: May 31, 2012
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Morihiro Seki, Katsumi Uesaka
  • Patent number: 8180183
    Abstract: An RF photonic link having at least one light source, at least one photodetector, multiple optoelectronic modulators, and an RF waveguide common to each one of said multiple optoelectronic modulators. The multiple optoelectronic modulators are optically arranged in parallel to receive light from said at least one light source and are disposed in said RF waveguide. The RF waveguide, in use, guides an RF electromagnetic field applied to each of the multiple optoelectronic modulators disposed therein, the RF electromagnetic field propagating through the RF waveguide in a direction that is perpendicular to a direction in which an optical field propagates through each of said optoelectronic modulators.
    Type: Grant
    Filed: July 18, 2008
    Date of Patent: May 15, 2012
    Assignee: HRL Laboratories, LLC
    Inventor: Daniel Yap
  • Patent number: 8175465
    Abstract: Examples of apparatus and methods are provided for controlling a bias in an optical modulator. An exemplary apparatus may comprise an optical modulator operable to modulate an optical signal. The optical modulation apparatus may comprise a photodetector disposed to receive at least a portion of the modulated optical signal. The optical modulation apparatus may comprise a bias controller coupled to both the optical modulator and the photodetector. The bias controller may be configured to receive a dither signal and to produce a bias feedback signal for the optical modulator. The bias feedback signal may be based on a ratio between an odd order harmonic signal of the modulated optical signal and an even order harmonic signal of the modulated optical signal.
    Type: Grant
    Filed: November 10, 2009
    Date of Patent: May 8, 2012
    Assignee: Lockheed Martin Corporation
    Inventors: Leah Wang, Anthony C. Kowalczyk
  • Publication number: 20120106888
    Abstract: In a nest MZI modulator in which each arm includes a child MZI, the power consumption is reduced. The hybrid integrated-type nest MZI modulator of the embodiment 1a is configured so that, instead of placing a relative phase adjusting section in a parent MZI, a bias electrode Bias 90° in which an electric field is applied in the same direction to the polarization direction in both of the upper and lower arms is placed in each child MZI (see FIG. 4B). The bias electrode Bias 90° provided in each child MZI constitute the entirety of a relative phase adjusting section. The optical signals are subjected to a phase change after the output from the child MZI (see FIG. 1A), because such relative phase adjusting section can subject the optical signals of the upper and lower arms of the child MZI to a shift change in the same direction, respectively.
    Type: Application
    Filed: July 9, 2010
    Publication date: May 3, 2012
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Takashi Goh, Yoshiyuki Doi, Shinji Mino, Ken Tsuzuki, Hiroshi Yamazaki, Takashi Yamada
  • Publication number: 20120099813
    Abstract: A phase shifter includes an optical waveguide, a plurality of impurity regions and a plurality of electrodes. The optical waveguide receives an optical input signal and outputs an optical output signal. The impurity regions include respective charge carriers. The impurity regions are disposed in contact with the optical waveguide at respective contact surface, where at least one of the contact surfaces has a zigzag pattern. The electrodes are connected to the respective impurity regions. Application of an electrical signal to at least one of the electrodes phase-shifts the optical output signal with respect to the optical input signal. Therefore, the phase shifter may efficiently vary a magnitude of the phase shift of the optical output signal.
    Type: Application
    Filed: September 22, 2011
    Publication date: April 26, 2012
    Inventors: Kwang-Hyun Lee, Dong-Jae Shin, Kyoung-Ho Ha
  • Publication number: 20120087617
    Abstract: An optical modulator includes a modulator that modulates an input light of light by using an input signal. The optical modulator further includes a compensation circuit that compensates the phase of a signal light in accordance with an input current, the signal light being the input light modulated by the modulator. The optical modulator further includes a detector that detects the difference between the phase of the signal light compensated by the compensation circuit and the phase of an input signal that is input to the modulator. The optical modulator further includes an adjustment circuit that adjusts, in accordance with the phase difference detected by the detector, the input current that is input to the compensation circuit.
    Type: Application
    Filed: July 28, 2011
    Publication date: April 12, 2012
    Applicant: FUJITSU OPTICAL COMPONENTS LIMITED
    Inventor: Tsuyoshi MORISHITA
  • Patent number: 8155484
    Abstract: An all-optical device for data processing is presented. The device comprises at least one optical waveguide unit (10) made of linear media and configured to provide multiple total internal reflections of light passing therethrough, the waveguide unit (10) comprising a waveguide portion (11) for interaction between reflected light components of input light; an input aperture arrangement (14) formed by at least one input aperture at an input facet of the waveguide portion (11); and an output aperture arrangement form by at least one output aperture at an output facet of the waveguide portion.
    Type: Grant
    Filed: February 9, 2006
    Date of Patent: April 10, 2012
    Assignees: Bar Ilan University, Ramot At Tel-Aviv University Ltd.
    Inventors: Zeev Zalevsky, Arkadi Roudnitski, Menachem Natan
  • Patent number: 8149492
    Abstract: An optical modulator has an optical splitter for splitting an input light beam into a first and second light beam; a first and a second wave-guide arm connected to the optical splitter for receiving and transmitting therethrough the first and second light beam, respectively, the waveguide arms each including a core region having group IV semiconductor material or a combination of group IV semiconductor materials; an optical combiner connected to the first and second waveguide arm for receiving the first and second light beam and combining them into an output light beam; a first and a second electrode structure associated with the first and second waveguide arm, respectively; and a driving circuit for supplying voltage to the first and second electrode structure. The driving circuit is adapted to supply a first modulation voltage super-imposed to a first bias voltage to the first electrode structure and a second modulation voltage superimposed to a second bias voltage to the second electrode structure.
    Type: Grant
    Filed: March 31, 2004
    Date of Patent: April 3, 2012
    Assignee: Google Inc.
    Inventors: Silvia Ghidini, Antonio Nespola
  • Patent number: 8135242
    Abstract: In an optical modulator, an intermediate substrate is provided separate from a main substrate on which a plurality of optical modulation sections are provided in parallel, and signal lines corresponding to the optical modulation sections are formed on the intermediate substrate. The signal lines are connected to signal electrodes corresponding to the main substrate, and have electrical lengths that are different from each other. Furthermore, the propagation loss per unit length in the signal lines on the intermediate substrate is preferably less than the propagation loss per unit length in the signal electrodes on the main substrate. As a result, even if a plurality of optical modulation sections are arranged in parallel, and the input ends of the signal electrodes of the optical modulation sections are arranged side by side on one side face of the substrate, synchronized modulation light of a low noise at a wide band width can be output from the optical modulation sections.
    Type: Grant
    Filed: December 11, 2009
    Date of Patent: March 13, 2012
    Assignee: Fujitsu Limited
    Inventor: Masaki Sugiyama
  • Publication number: 20120057815
    Abstract: An optical modulation device of an embodiment includes: a first p-type semiconductor region; a first n-type semiconductor region; a first low-impurity-density semiconductor region formed between the first p-type semiconductor region and the first n-type semiconductor region; a second n-type semiconductor region formed on an outer side of the first p-type semiconductor region via a second low-impurity-density semiconductor region; and a second p-type semiconductor region formed on an outer side of the first n-type semiconductor region via a third low-impurity-density semiconductor region. The carrier density in the first low-impurity-density semiconductor region is changed by current injection. The phase of light propagated through an optical waveguide structure that includes at least part of the first low-impurity-density semiconductor region is modulated.
    Type: Application
    Filed: March 30, 2011
    Publication date: March 8, 2012
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Mizunori Ezaki, Nobuo Suzuki
  • Publication number: 20120039560
    Abstract: The present invention provides optical devices that employ nonlinear optical effects for processing optical signals. For example, such an optical device can include a nano-sized interferometric component that provides an optical output signal via interference of two input signals subsequent to their asymmetric nonlinear phase accumulation. The interferometric element can have a variety of configurations, such as Sagnac, Mach-Zehnder or Michelson configurations.
    Type: Application
    Filed: January 8, 2010
    Publication date: February 16, 2012
    Applicant: President & Fellows of Harvard College
    Inventors: Eric Mazur, Rafael R. Gattass, Geoffry T. Svacha, Katherine C.f. Phillips, Christopher C. Evans
  • Patent number: 8116600
    Abstract: Provided is a small-size optical phase modulation element and an optical modulator using it. The optical phase modulation element includes a Plasmon waveguide having a clad made of a metal material having a complex dielectric constant having a negative real part in the used wavelength and a core formed by a dielectric metal material having a complex dielectric constant having a positive real part in the used wavelength. The Plasmon waveguide is connected to an optical waveguide including a clad and a core both having a complex dielectric constant having a positive real part. The core of the Plasmon waveguide and the core of the optical waveguide are formed, at least partially, of the same semiconductor material. The Plasmon waveguide has a function to phase-modulate the incident light when voltage is applied.
    Type: Grant
    Filed: December 25, 2007
    Date of Patent: February 14, 2012
    Assignee: NEC Corporation
    Inventors: Daisuke Okamoto, Masafumi Nakada, Junichi Fujikata
  • Publication number: 20120033910
    Abstract: An electro-optic modulation component is provided, in particular on an SOI (semiconductor-on-insulator) substrate, improved for better performance at data rates above 10 Gb/s. This improvement is obtained by reducing the influence of the capacitive effects of the structure and of its environment, and more particularly in which the influence of the capacitance of the structure itself is limited by reducing the access resistance in the doped regions or the influence of the capacitive effect of the environment is reduced by modifying the structure of the substrate vertically beneath the active region, for example by thinning the silicon substrate or the insulator, or a combination of these features. The invention furthermore relates to a process for fabricating such a component and to a device or system that includes such a component. These improvements are applicable in 3D integration assembly processes and to electronic and optical hybrid circuits.
    Type: Application
    Filed: March 24, 2010
    Publication date: February 9, 2012
    Inventors: Delphine Morini, Gilles Rasigade, Laurent Vivien
  • Publication number: 20120027337
    Abstract: In order to provide an optical modulator capable of suppressing generation of mode mismatching light in the Y-multiplexer in the MZ-type waveguide or mixing of the mode mismatching light with the radiation-mode light or the output light, and separately extracting output light and radiation-mode light, there is provided an optical modulator having a Mach-Zehnder type waveguide on a surface of a dielectric substrate, wherein a waveguide after multiplexing in a Y-multiplexer in an output side of the Mach-Zehnder type waveguide is a multiple mode waveguide 2, a subsidiary output waveguide as a high-order mode waveguide 2 is connected to a portion where the multiple mode waveguide is changed to a main output waveguide 3 as a single mode waveguide, and the multiple mode waveguide 2 has a length equal to or longer than 150 ?m.
    Type: Application
    Filed: March 30, 2010
    Publication date: February 2, 2012
    Applicant: Sumitomo Osaka Cement Co., Ltd.
    Inventors: Katsutoshi Kondou, Satoshi Oikawa, Toru Sugamata
  • Publication number: 20120027336
    Abstract: Provided is a Mach-Zehnder modulator. The Mach-Zehnder modulator comprises an input wave guide and an output wave guide arranged on a substrate, a first branch wave guide and a second branch wave guide connected in parallel between the input and output wave guides, and a connecting region configured to connect the first branch wave guide and the second branch wave guide. Each of the first and second branch wave guides comprises first doped regions doped with a first dopant and second doped regions doped with a second dopant having different conductivity from the first dopant, and the connecting region is doped with the first dopant and arranged between the first regions of the first and second branch wave guides.
    Type: Application
    Filed: December 21, 2010
    Publication date: February 2, 2012
    Applicant: Electronics and telecommunications Research Institute
    Inventors: Jeong Woo PARK, Gyungock Kim
  • Patent number: 8098965
    Abstract: A novel electroabsorption modulator based on tuning the Fermi level relative to mid-gap states in a semiconductor. The modulator includes a semiconductor waveguide that has an input port and an output port. Between the input port and the output port is a section of the waveguide that functions as an electroabsorptive region. Adjacent to the electroabsorptive region are electrical contacts. In operation by adjusting voltages on the electrical contacts, the quasi-Fermi level in the electroabsorptive region of the semiconductor waveguide is brought above or below mid band-gap electronic states. As these states transition between occupancy and vacancy, the absorption coefficient for optical radiation in the electroabsorptive region of the semiconductor changes.
    Type: Grant
    Filed: December 3, 2009
    Date of Patent: January 17, 2012
    Assignee: University of Washington
    Inventors: Tom Baehr-Jones, Michael J. Hochberg