With Particular Direction Of The Field In Relation To The Medium, Beam Direction Or Polarization Patents (Class 359/283)
  • Patent number: 10321552
    Abstract: In an undulator magnet array, an upper magnet array is formed by coupling an upper shift magnet array and an upper reference magnet array, and a lower magnet array is formed by coupling a lower reference magnet array and lower shift magnet array arranged so as to face the magnet arrays. With reference to a state where the amplitudes of periodic magnetic fields that can be formed by the upper magnet array and the lower magnet array are maximized, the upper shift magnet array is shifted ¼ of a period to the left as seen from the lower reference magnet array and the lower shift magnet array is shifted ¼ of a period to the left as seen from the upper reference magnet array.
    Type: Grant
    Filed: October 8, 2015
    Date of Patent: June 11, 2019
    Assignee: RIKEN
    Inventors: Ryota Kinjo, Takashi Tanaka
  • Patent number: 9683168
    Abstract: To reduce impurity contents of carbon and oxygen not contributing to light emission, then suppress deterioration of emission intensity of a phosphor, and improve emission efficiency of this phosphor. Therefore, there is provided a firing method of nitride or oxynitride phosphors, wherein a crucible 11 made of nitride is used as a firing container, and firing is performed, with this crucible covered with a lid (container 10), to manufacture the phosphor. The phosphor is expressed by a general composition formula MABOoN3-2/3O:Z in which element M is one or more kinds of elements having bivalent valency, element A is one or more kinds of elements having tervalent valency, element B is one or more kinds of elements having tetravalent valency, O is oxygen, N is nitrogen, and element Z is an activating agent, satisfying o?0.
    Type: Grant
    Filed: September 7, 2007
    Date of Patent: June 20, 2017
    Assignees: NICHIA CORPORATION, CITIZEN ELECTRONICS CO., LTD.
    Inventors: Masahiro Gotoh, Kenji Sakane
  • Patent number: 9478333
    Abstract: The invention relates to a process of and apparatus for forming a magnetic structure on a substrate and a magnetic structure formed by such a process and apparatus. The magnetic structure comprises a matrix in which magnetic particles are embedded. The apparatus for forming the magnetic structure on the substrate comprises a source of matrix deposits the matrix material onto the substrate to form the matrix, and comprises a source of magnetic particles which deposit the magnetic particles onto the matrix as the matrix forms to embed the magnetic particles in the matrix. Each magnetic particle comprises a core covered with a layer of metal, at least one of the matrix material and the core is of ferromagnetic material and the core and the layer of metal are of different materials.
    Type: Grant
    Filed: September 17, 2013
    Date of Patent: October 25, 2016
    Assignee: Nano Resources Limited
    Inventors: Robert Davidson Binns, Christopher Robin Binns
  • Patent number: 8854715
    Abstract: A magnetic field may be applied to a plasmon path to affect plasmon propagation.
    Type: Grant
    Filed: September 14, 2012
    Date of Patent: October 7, 2014
    Inventors: Jeffrey A. Bowers, Peter L. Hagelstein, Roderick A. Hyde, Muriel Y. Ishikawa, Jordin T. Kare, Clarence T. Tegreene, Lowell L. Wood, Jr., Victoria Y. H. Wood
  • Patent number: 8693873
    Abstract: The present disclosure describes a reconfigurable optical add-drop multiplexer. The reconfigurable optical add-drop multiplexer includes a first optical equalizer to precompensate a received optical signal for optical filtering effects to produce a first compensated optical signal. A first interleaver, coupled to the first optical equalizer, separates the first compensated optical signal into an odd optical signal and an even optical signal. A plurality of wavelength selective switches processes the odd optical signal and the even optical signal. A second interleaver, combines the odd optical signal and the even optical signal to produce a combined optical signal. A second optical equalizer, coupled to the second interleaver, postcompensates the combined optical signal for optical filtering effects to produce an output optical signal.
    Type: Grant
    Filed: December 2, 2011
    Date of Patent: April 8, 2014
    Assignee: AT&T Intellectual Property I, L.P.
    Inventor: Xiang Zhou
  • Patent number: 8274731
    Abstract: A magnetic field may be applied to a plasmon path to affect plasmon propagation.
    Type: Grant
    Filed: April 16, 2010
    Date of Patent: September 25, 2012
    Inventors: Jeffrey A. Bowers, Peter L. Hagelstein, Roderick A. Hyde, Muriel Y. Ishikawa, Jordin T. Kare, Clarence T. Tegreene, Lowell L. Wood, Jr., Victoria Y. H. Wood
  • Patent number: 8058869
    Abstract: The device includes two supports and a primary conductive strip. The primary conductive strip includes a neutral surface, a first side, and a second side. The primary conductive strip is connected one of directly and indirectly on the first side to the two supports such that the primary conductive strip is constrained in two dimensions and movable in one dimension. The device also includes a primary distributed feedback fiber laser. The primary distributed feedback fiber laser includes a fiber axis. The primary distributed feedback fiber laser is connected to the primary conductive strip along one of the first side and the second side such that there is a positive distance between the neutral surface of the primary conductive strip and the fiber axis of the primary distributed feedback fiber laser.
    Type: Grant
    Filed: October 21, 2008
    Date of Patent: November 15, 2011
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventors: Geoff A Cranch, Gordon M. A. Flockhart
  • Patent number: 7982000
    Abstract: The present invention provides a solid material comprising an immobilized mixture of two or more proteorhodopsins, two or more bacteriorhodopsins, or one or more bacteriorhodopsin and one or more proteorhodopsins. The proteorhodopsins are selected from the group consisting of all-trans-retinal-containing proteorhodopsins and retinal analog-containing proteorhodopsins; all of which have absorption spectra that do not overlap. The bacteriorhodopsins are selected from the group consisting of all-trans-retinal-containing bacteriorhodopsins and retinal analog-containing bacteriorhodopsins; all of which have absorption spectra that do not overlap. The present invention also provides an optical information carrier, such as an optical data storage material and a fraud-proof optical data carrier, comprising the above-described solid material and a substrate selected from the group consisting of glass, paper, metal, fabric material, and plastic material, wherein said solid material is deposited on said substrate.
    Type: Grant
    Filed: June 9, 2005
    Date of Patent: July 19, 2011
    Assignee: Danisco US Inc.
    Inventors: Richard R. Bott, Rasmus B. Jensen, Bradley R. Kelemen, Donald E. Ward, II, Gregory M. Whited
  • Publication number: 20110115469
    Abstract: An optical fiber electric current sensor includes a polarization-splitter (13) that splits light outputted from a sensor fiber (11) into two polarization planes of which polarization directions are perpendicular to each other, a depolarizer (17) that depolarizes each of the polarization components from the polarization-splitter (13), light receiving element that converts the two lights that were depolarized by the depolarizer (17) to a first signal (S1) and a second signal (S2) respectively, and a signal processing unit (15) that, based on the first signal (S1) and the second signal (S2), determines the magnitude of a Faraday rotation applied to the linearly-polarized light, and thereby calculates a value of the current to be measured.
    Type: Application
    Filed: July 15, 2009
    Publication date: May 19, 2011
    Applicants: THE TOKYO ELECTRIC POWER COMPANY, INCORPORATED, TAKAOKA ELECTRIC MFG. CO., LTD.
    Inventors: Reishi Kondo, Kiyoshi Kurosawa, Shinsuke Nasukawa, Taro Kuramochi, Toshiharu Yamada, Eiji Itakura
  • Patent number: 7843622
    Abstract: An active optical filter transmits or blocks light according to whether or not a magnetic field is applied, and functions as an optical filter transmitting light having a predetermined wavelength when light is transmitted according to a magnetic field. The active optical filter includes: an optical filter layer for transmitting or blocking light according to whether or not a magnetic field is applied; and a magnetic field applying unit surrounding the optical filter layer for applying a magnetic field to the optical filter layer. The optical filter layer has a multi-layer thin layer structure which is formed of two kinds of thin layers having different respective refractive indices and sequentially and periodically stacked on a substrate.
    Type: Grant
    Filed: December 30, 2008
    Date of Patent: November 30, 2010
    Assignees: Samsung Electronics Co., Ltd., Samsung SDI Co., Ltd.
    Inventor: Pil-soo Ahn
  • Patent number: 7837331
    Abstract: An illuminator includes a light source that outputs light, a polarization separation device that separates the light outputted from the light source into polarization components of the first and second oscillation directions, the polarization components having mutually orthogonal polarizations, and a polarization conversion device that converts the polarization component of the second oscillation direction divided by the polarization separation device to the polarization component of the first oscillation direction. The polarization component of the first oscillation direction divided by the polarization separation device and the polarization component of the first oscillation direction converted by the polarization conversion device are incident on an incident surface of an illumination target from different directions from each other.
    Type: Grant
    Filed: December 13, 2006
    Date of Patent: November 23, 2010
    Assignee: Seiko Epson Corporation
    Inventor: Susumu Aruga
  • Patent number: 7751112
    Abstract: A magnetic field may be applied to a plasmon path to affect plasmon propagation.
    Type: Grant
    Filed: December 9, 2008
    Date of Patent: July 6, 2010
    Inventors: Jeffrey A. Bowers, Peter L. Hagelstein, Roderick A. Hyde, Muriel Y. Ishikawa, Jordin T. Kare, Clarence T. Tegreene, Lowell L. Wood, Jr., Victoria Y. H. Wood
  • Patent number: 7535616
    Abstract: A polarization controlling apparatus includes a permanent magnet itself or a permanent magnet to which a part capable of being magnetized is applied, an electromagnet capable of changing the magnitude of a magnetic field to be generated thereby, and a Faraday rotation effect element. The Faraday rotation effect element is disposed at a position at which an interaction magnetic field acts on the Faraday rotation effect element. The interaction magnetic field is produced by an interaction between a magnetic field generated by the permanent magnet and a magnetic field generated by the electromagnet. The Faraday rotation effect element thereby produces a Faraday rotation effect on inputted light. The magnitude of the interaction magnetic field in the Faraday rotation effect element is varied by a magnetic field component generated by the electromagnet to vary the amount of the Faraday rotation effect to be had on the inputted light.
    Type: Grant
    Filed: September 29, 2006
    Date of Patent: May 19, 2009
    Assignee: Fujitsu Limited
    Inventors: Kazuo Hironishi, Nobuhiro Fukushima, Jens Rasmussen
  • Publication number: 20090052007
    Abstract: A reflective magnetic display includes a magnetic material layer region formed between front and rear substrates, wherein the magnetic material layer region has magnetic particles that reflect or absorb incident light when magnetic moments are randomly oriented and reflect or transmit the incident light in, accordance with polarization of the incident light, when the magnetic moments are aligned in a direction and an electrode that is designed to apply a magnetic field inducing a magnetic moment alignment on the magnetic material layer region in accordance with electrical operation.
    Type: Application
    Filed: March 28, 2008
    Publication date: February 26, 2009
    Applicant: Samsung Electronics Co., Ltd.
    Inventors: Su-mi LEE, Moon-gyu LEE, Yoon-sun CHOI, Seong-mo HWANG, Sung Nae CHO
  • Patent number: 7466878
    Abstract: A polarization controller includes a phase retarder having a rotation about an {1,0,0} axis that receives an optical signal from a waveguide structure. At least one nanoelectromechanical dielectric perturber produces ±45° birefringent axes by placing the at least one nanoelectromechanical dielectric perturber at selective positions around the phase retarder to produce dynamic change in the effective index in one of the modes existent in an extraordinary axial direction.
    Type: Grant
    Filed: February 10, 2006
    Date of Patent: December 16, 2008
    Assignee: Massachusetts Institute of Technology
    Inventors: Poh-Boon Phua, Chee Wei Wong, Erich P. Ippen
  • Patent number: 7444040
    Abstract: The invention relates to a magneto-optical component, such as a variable light attenuator, light modulator or optical switch, having small size, low power consumption and high speed. The magneto-optical component comprises at least one Faraday rotator comprising a magnetic domain A with magnetization in a direction perpendicular to a light incident/exit surface, a magnetic domain B with magnetization in a direction opposite to the magnetization direction of the magnetic domain A, a planar magnetic domain wall as a boundary between the magnetic domain A and the magnetic domain B, and two light transmission regions through which a plurality of light beams comprising identical traveling directions are transmitted respectively and whose distances from the magnetic domain wall are almost equal to each other, and a magnetic field application system for applying a variable magnetic field to the Faraday rotator to make a position of the magnetic domain wall variable.
    Type: Grant
    Filed: January 21, 2005
    Date of Patent: October 28, 2008
    Assignee: TDK Corporation
    Inventor: Shinji Iwatsuka
  • Patent number: 7433558
    Abstract: Methods for optical isolation in high peak power fiber-optic systems prevent damage to a facet within a fiber-optic isolator caused by back-reflected light from, for example, an optical amplifier. Preventing damage to the facet may include expanding a mode area of the back-reflected light and/or reducing a change in refractive index.
    Type: Grant
    Filed: October 29, 2007
    Date of Patent: October 7, 2008
    Assignee: Raydiance, Inc
    Inventors: Timothy J. Booth, Ismail T. Yilmaz, James F. Brennan, III
  • Patent number: 7379226
    Abstract: A variable optical attenuator comprising a separation/combination birefringent element, fixed polarization rotation means, a convex lens, variable polarization rotation means, and a mirror which are arranged in that order. The fixed polarization rotation means has a compensation film Faraday element placed in a cylindrical permanent magnet, and the variable polarization rotation means has a base film Faraday element that is placed outside the cylindrical permanent magnet, and an electromagnet applying a variable magnetic field thereto. Thereby, both the Faraday elements are magnetized in directions different from each other.
    Type: Grant
    Filed: July 30, 2007
    Date of Patent: May 27, 2008
    Assignee: FDK Corporation
    Inventors: Teruhisa Nakamura, Hidenori Nakata, Kenji Sahara, Yuko Ohta
  • Patent number: 7308171
    Abstract: Methods and apparatus for optical isolation in high peak power fiber-optic systems prevent damage to a facet within a fiber-optic isolator caused by back-reflected light from, for example, an optical amplifier. Preventing damage to the facet may include expanding a mode area of the back-reflected light and/or reducing a change in refractive index.
    Type: Grant
    Filed: November 16, 2005
    Date of Patent: December 11, 2007
    Assignee: Raydiance, Inc.
    Inventors: Timothy J. Booth, Ismail T. Yilmaz, James F. Brennan, III
  • Publication number: 20070242340
    Abstract: A polarization controlling apparatus is disclosed, which enhances the degree of freedom in apparatus design. The polarization controlling apparatus includes a permanent magnet itself or a permanent magnet to which a part capable of being magnetized is applied, an electromagnet capable of changing the magnitude of a magnetic field to be generated thereby, and a Faraday rotation effect element, disposed at a position at which an interaction magnetic field produced by an interaction between a magnetic field generated by the permanent magnet and a magnetic field generated by the electromagnet acts, for producing a Faraday rotation effect on inputted light by means of the interaction magnetic field. The magnitude of the interaction magnetic field in the Faraday rotation effect element is varied by a magnetic field component generated by the electromagnet to vary the amount of the Faraday rotation effect to be had on the inputted light.
    Type: Application
    Filed: September 29, 2006
    Publication date: October 18, 2007
    Inventors: Kazuo Hironishi, Nobuhiro Fukushima, Jens Rasmussen
  • Patent number: 7280264
    Abstract: It is possible to reduce the size of a magneto-optical device, increase the speed of optical control, simplify power supply structure and its control, and maintain a Faraday rotation angle in an arbitrary state even after shut-off of the excitation current. The magneto-optical device includes a magnetic yoke (10) made of a high-permeability magnetic material, the magnetic yoke including a tabular portion (16) and four pillar portions (18) protruding from one side of the tabular portion (16), a coil (12) wound on each of the pillar portions, and a magneto-optical element (14) arranged in an open-magnetic-circuit region surrounded by the end portions of the four pillar portions. A magnetic field obtained by a coil is applied to the magneto-optical element.
    Type: Grant
    Filed: August 26, 2004
    Date of Patent: October 9, 2007
    Assignee: FDK Corporation
    Inventors: Yuji Goto, Mikio Kitaoka, Hiromitsu Umezawa, Tsugio Tokumasu, Toshihiko Watanabe, Akitoshi Mesaki, Takashi Kato, Masaharu Hoshikawa, Chiharu Nishida
  • Patent number: 7206116
    Abstract: A Faraday rotator for a Faraday isolator with an input polarizer, with an output polarizer, with a roller-shaped optical crystal that is arranged therebetween and that is arranged symmetrical to its axis of symmetry, with a right hollow cylinder that surrounds this and has a hollow space made of a permanent magnetic material, which cylinder is axially magnetized and the magnetic field of which extends in the hollow space approximately parallel to the axis of symmetry that runs in only one direction from the north pole to the south pole, and with terminal magnets attached to each of the two end faces in the plane perpendicular to the y- and z-directions of the axis of symmetry, each of which is embodied as a hollow right cylinder and has a through-aperture in the extension of the axis of symmetry, is characterized in that each terminal magnet is largely radially magnetized with regard to the axis of symmetry at least by region, in that the one of the two terminal magnets is magnetized radially from interior to
    Type: Grant
    Filed: April 21, 2004
    Date of Patent: April 17, 2007
    Assignee: Linos Photonics GmbH & Co. KG
    Inventors: Thomas Fehn, Sven Poggel, Stefan Balle
  • Patent number: 7167295
    Abstract: According to one aspect of the invention, a method and apparatus for polarizing electromagnetic radiation is provided. The electromagnetic radiation may be divided into first and second portions, substantially all of the first portion may be linearly polarized in a first direction and substantially all of the second portion may be linearly polarized in a second direction, the first direction being substantially orthogonal to the second direction. The linear polarization of at least one of the first and second portions may be changed such that substantially all of both of the first and second portions are linearly polarized in a third direction. At least one of the first and second portions may be redirected such that substantially all of both the first and second portions are propagating in a fourth direction.
    Type: Grant
    Filed: December 20, 2005
    Date of Patent: January 23, 2007
    Assignee: Intel Corporation
    Inventors: David L. Williams, James Kardach, Michael Goldstein
  • Patent number: 7095559
    Abstract: In a variable optical delay circuit to be used for compensation for polarization mode dispersion of an optical signal and for other purposes, there are provided a first birefringent member, a second birefringent member and a variable optical rotator interposed between the first birefringent member and the second birefringent member for varying a polarization state of light outputted from the first birefringent member. The birefringent members and the variable optical rotator are disposed on the same optical axis, and the optical axis of each of the birefringent members is set to perpendicularly intersect a traveling direction of inputted light. Therefore, by varying the optical rotation angle of the variable optical rotator, an arbitrary delay quantity corresponding thereto is obtainable in a continuous (analog-like) fashion without undergoing spatial separation between polarization components of the inputted light and varying the intensity (loss) of each of the polarization components.
    Type: Grant
    Filed: March 23, 2005
    Date of Patent: August 22, 2006
    Assignee: Fujitsu Limited
    Inventors: Shinji Taniguchi, Tadao Nakazawa, deceased, Yumi Nakazawa, legal representative, Masaharu Doi
  • Patent number: 7050216
    Abstract: A variable optical filter comprises a first polarizer, a first phase difference element operable to generate a phase difference, a variable Faraday rotator operable to impart a variable Faraday rotation, a second phase difference element operable to generate a phase difference, and a second polarizer, wherein said polarizers, said variable Faraday rotator, and said phase difference elements are arranged in the mentioned order along the optical axis, and wherein when the angles formed by the optic axes of said first and second phase difference elements and the transmitted polarization azimuth of the first polarizer are assumed respectively to be ?1 and ?2, these ?1 and ?2 are set to different angles.
    Type: Grant
    Filed: December 10, 2004
    Date of Patent: May 23, 2006
    Assignees: Fujitsu Limited, FDK Corporation
    Inventors: Nobuhiro Fukushima, Hidenori Nakada, Tsugio Tokumasu, Yuko Ota
  • Patent number: 7024073
    Abstract: A reflection-type variable optical attenuator comprises: a main attenuator unit including a first birefringent crystal plate, a Faraday rotational angle varying unit, and a second birefringent crystal plate arranged in this order; an input port and an output port that are arranged on a side of one end of the main attenuator unit; and a two-point reflection-type optical path varying reflector that is arranged on a side of the other end of the main attenuator unit. Light that comes in from the input port makes a round trip in the main attenuator unit and goes out through the output port.
    Type: Grant
    Filed: September 20, 2002
    Date of Patent: April 4, 2006
    Assignee: FDK Corporation
    Inventors: Teruhisa Sahashi, Hidenori Nakada, Shohei Abe, Isao Kojima, Keisuke Ikeda
  • Patent number: 7006273
    Abstract: Optical devices including a Faraday rotation devices improved in wavelength and temperature characteristics and an optical attenuator reduced in wavelength dependence and temperature-dependent loss. The Faraday rotation device has permanent magnets magnetized in an axial direction of through-holes, and Faraday elements having a same Faraday rotation direction with respect to a same magnetization direction. The permanent magnets are directed in the same magnetization direction along an optical path, where part of the Faraday elements are accommodated in the through-hole of the permanent magnet, and the remaining Faraday elements are arranged between the magnets, whereby the Faraday elements are to be applied by magnetic fields in opposite directions. For a device variable in Faraday rotation angle, an electromagnet is provided. An input fiber collimator and polarizer are provided on an input side of with the Faraday elements while an analyzer and output fiber collimator are on an output side.
    Type: Grant
    Filed: December 17, 2004
    Date of Patent: February 28, 2006
    Assignee: FDK Corporation
    Inventors: Teruhisa Sahashi, Hidenori Nakada, Hirotaka Kawai, Isao Kojima, Tsugio Tokumasu
  • Patent number: 7002732
    Abstract: The invention provides small-sized, power-saving and easily-producible magneto-optical devices. The magneto-optical device comprises a Faraday rotator having nearly parallel surfaces and a Z-direction magnetic easy axis; a total reflection film formed partly on one surface of the Faraday rotator; another total reflection film formed partly on the other surface thereof; a light input region through which light enters the Faraday rotator; a light output region through which the light having alternately reflected on the total reflection films goes out of the Faraday rotator; a permanent magnet that forms a predetermined magnetic domain structure in the Faraday rotator and applies a magnetic field component in the Z-direction to the Faraday rotator so that the magnetization direction could be the same both in the light input region and the light output region; and an electromagnet that varies the position at which the magnetic field component applied to the Faraday rotator is 0 (zero).
    Type: Grant
    Filed: August 24, 2004
    Date of Patent: February 21, 2006
    Assignee: TDK Corporation
    Inventor: Shinji Iwatsuka
  • Patent number: 6943932
    Abstract: A device and method for optical isolation for use in optical systems is disclosed. The device provides for a waveguide optical isolator fabricated using two arms, made of optical waveguides comprising magneto-optical material, in a Mach-Zehnder interferometer configuration. The device of the present invention operates using the TM mode of a light wave and, thus, does not require phase-matching of TM and TE modes. Further, the present invention does not use polarizers to extinguish the optical feed-back.
    Type: Grant
    Filed: April 20, 2001
    Date of Patent: September 13, 2005
    Assignee: The Trustees of Columbia University in the City of New York
    Inventors: Junichiro Fujita, Miguel Levy, Richard M Osgood
  • Patent number: 6927909
    Abstract: The integrated magneto-optical modulator with optical isolator of the present invention comprises an optical isolator unit, a magneto-optical modulator unit, an impedance adjuster. The optical isolator unit rotates a polarization of an incident light from a light source to transmit the light with rotated polarization, and eliminates a reflected feedback light toward the light source. The magneto-optical modulator unit modulates an intensity of the light from the optical isolator unit and transmitting the modulated light outside. The impedance adjuster adjusts electrical impedance at the magneto-optical modulator unit in order to effectively introduce the high-frequency signal for light modulation to the magneto-optical modulator unit. Further, the optical isolator unit and the magneto-optical modulator unit are contained a single package.
    Type: Grant
    Filed: May 8, 2003
    Date of Patent: August 9, 2005
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventor: Hisashi Minemoto
  • Patent number: 6912080
    Abstract: The magneto-optic modulator rotates a polarization of a light incident to a magneto-optic device which causes Faraday effect under such a magnetic field arrangement that the RF magnetic field has a component perpendicular to a light propagation direction and the RF magnetic field is directed to more than ±30° from the bias magnetic field direction. The bias magnetic field generator may be a permanent magnet, while the RF magnetic field generator may be a strip line running along a waveguide for the incident light. The strip line is fed by an RF electric current signal. The light beam is modulated at a frequency as high as about 10 GHz. The modulation depth can be further improved by using an impedance transformer and magnetic core.
    Type: Grant
    Filed: March 20, 2003
    Date of Patent: June 28, 2005
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventor: Hisashi Minemoto
  • Patent number: 6906843
    Abstract: An optical isolator comprising a combination of an optical isolator main body and a holder holding the optical isolator main body, the optical isolator main body including a Faraday rotator element, a polarizer and an analyzer disposed at the front and back of the Faraday rotator element, and permanent magnets disposed on the outside of the Faraday rotator element, the polarizer and the analyzer.
    Type: Grant
    Filed: November 22, 2004
    Date of Patent: June 14, 2005
    Assignee: FDK Corporation
    Inventors: Mitsuru Nagasawa, Hirotaka Kawai
  • Patent number: 6876480
    Abstract: Optical devices including a Faraday rotation devices improved in wavelength and temperature characteristics and an optical attenuator reduced in wavelength dependence and temperature-dependent loss. The Faraday rotation device has permanent magnets magnetized in an axial direction of through-holes, and Faraday elements having a same Faraday rotation direction with respect to a same magnetization direction. The permanent magnets are directed in the same magnetization direction along an optical path, where part of the Faraday elements are accommodated in the through-hole of the permanent magnet, and the remaining Faraday elements are arranged between the magnets, whereby the Faraday elements are to be applied by magnetic fields in opposite directions. For a device variable in Faraday rotation angle, an electromagnet is provided. An input fiber collimator and polarizer are provided on an input side of with the Faraday elements while an analyzer and output fiber collimator are on an output side.
    Type: Grant
    Filed: July 25, 2001
    Date of Patent: April 5, 2005
    Assignee: FDK Corporation
    Inventors: Teruhisa Sahashi, Hidenori Nakada, Hirotaka Kawai, Isao Kojima, Tsugio Tokumasu
  • Patent number: 6876481
    Abstract: A spatial light modulator includes: a magnetic layer that is made of a magneto-optic material and includes a plurality of pixels in each of which a magnetization direction is independently set and each of which has a function of causing a rotation of a polarization direction of incident light depending on the magnetization direction by a magneto-optic effect; a plurality of first conductor layers and a plurality of second conductor layers arranged to intersect with each other at positions corresponding to the individual pixels, through which currents for generating magnetic fields to set the magnetization directions in the individual pixels are passed; and a plurality of dielectric layers for enhancing the function of the pixels. A polarization direction of light incident on the spatial light modulator is rotated depending on the magnetization direction of each pixel.
    Type: Grant
    Filed: June 13, 2001
    Date of Patent: April 5, 2005
    Assignee: Optware Corporation
    Inventors: Mitsuteru Inoue, Jae-Kyong Cho
  • Patent number: 6870675
    Abstract: A variable optical attenuator is disclosed which comprises a plane-parallel birefringent element for separation/synthesis which separates light beams having orthogonal polarization directions on the same optical path, the birefringent element synthesizing light beams on different optical paths; a light converging lens disposed adjacent to the birefringent element for separation/synthesis; a reflecting mirror disposed at a focal point of the lens opposite to the birefringent element for separation/synthesis with respect to the lens; a variable polarization rotating device; and an input port and an output port which are disposed at the end of the birefringent element for separation/synthesis; the variable polarization rotating device being disposed at any position between the birefringent element for separation/synthesis and the reflecting mirror, the variable polarization rotating device controlling the rotational angle of the polarization direction of incident light beams from the input port, to thereby contr
    Type: Grant
    Filed: September 27, 2002
    Date of Patent: March 22, 2005
    Assignee: FDK Corporation
    Inventors: Keisuke Ikeda, Shohei Abe, Isao Kojima, Yuko Ota, Ikuo Maeda
  • Patent number: 6859298
    Abstract: Disclosed is an optical module of an isolator structure including a semiconductor laser, a polarizer, and a Faraday rotator. The laser outputs a first linearly-polarized beam of a predetermined polarization mode. The polarizer is positioned to face an end of the laser, and its polarization axis is tilted at a 45° angle with respect to the polarization direction of the first beam. The Faraday rotator is disposed between the laser and the polarizer, and rotate the polarization direction of the first beam by 45° to substantially coincide with the polarization axis of the polarizer, and then output it to the polarizer, and to rotate a second beam from the polarizer by 45°, wherein the second beam has a polarization mode polarized perpendicular to the first beam, and then output it to the semiconductor laser.
    Type: Grant
    Filed: November 14, 2003
    Date of Patent: February 22, 2005
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Shi-Yun Cho
  • Patent number: 6833941
    Abstract: To provide a magneto-optic optical device, such as a variable optical attenuator, an optical modulator or an optical switch, that is small, has a low power consumption and has high speed. The above object is achieved by a magneto-optic optical device characterized by comprising at least one magneto-optical crystal, a magnetic field application mechanism for applying to the magneto-optical crystal a magnetic field component in a direction vertical to a light entrance/exit plane, and at least one electromagnet for changing a position where the magnetic field component applied to the magneto-optical crystal becomes zero.
    Type: Grant
    Filed: August 1, 2003
    Date of Patent: December 21, 2004
    Assignee: TDK Corporation
    Inventor: Shinji Iwatsuka
  • Patent number: 6762872
    Abstract: A spatial light modulator includes a device portion and a bias field applying coil disposed around the device portion. The device portion includes a magnetic layer and two types of conductor layers. The magnetic layer is made of a magneto-optic material and includes a plurality of pixels whose directions of magnetization are set independently of one another. Each of the pixels causes rotation of a direction of polarization of incident light depending on its direction of magnetization due to a magneto-optic effect. The conductor layers generate a magnetic field for setting the direction of magnetization of each of the pixels of the magnetic layer. Each of the pixels includes two regions which can take different states of magnetization. Information is produced by changing the states of magnetization in those regions.
    Type: Grant
    Filed: December 3, 2002
    Date of Patent: July 13, 2004
    Assignee: Optware Corporation
    Inventors: Mitsuteru Inoue, Jae Kyong Cho
  • Patent number: 6747782
    Abstract: A Faraday rotator and an optical attenuator using the Faraday rotator in which both a fixed magnetic field parallel to and a valuable magnetic field perpendicular to the optical axis are applied to Faraday elements, said optical axis being in the <111> direction of single crystal of garnet, characterized in that three single crystals of garnet of substantially the same thickness having the Faraday effect are used to form Faraday elements and the Faraday elements are arranged in such a manner that a variable magnetic field is applied to one of the Faraday elements, over a range extending 5 deg. each to the left and right of the line connecting the (111) plane in the center of the stereographic projection chart with the (−1−12) plane on the outermost circumference or a plane equivalent thereto in the chart, whereas a variable magnetic field is applied to the remaining two elements, over a range extending 5 deg.
    Type: Grant
    Filed: May 21, 2002
    Date of Patent: June 8, 2004
    Assignee: TDK Corporation
    Inventors: Masanori Goto, Shinji Iwatsuka, Seiichi Takayama
  • Patent number: 6717713
    Abstract: An apparatus which attenuates a light signal polarized in a first direction. The apparatus includes a polarization rotation unit and an output unit. The polarization rotation unit rotates the polarization of the light signal to produce a polarization rotated light signal having a polarization component in the first direction and a polarization component in a second direction which is substantially 90 degrees with respect to the first direction. The output unit passes, as an output signal, the polarization component in the second direction of the polarization rotated light signal and blocks the polarization component in the first direction. The polarization rotation unit includes an electromagnet and a permanent magnet which apply magnetic fields in specific directions with respect to the light path. Various yoke constructions are provided for the electromagnet and the permanent magnet.
    Type: Grant
    Filed: April 11, 2003
    Date of Patent: April 6, 2004
    Assignee: Fujitsu Limited
    Inventors: Hiroshi Onaka, Nobuhiro Fukushima
  • Publication number: 20040027639
    Abstract: There is provided a magneto-optic optical device, such as a variable optical attenuator, an optical modulator or an optical switch, which is small, has a low power consumption, and has a high speed. A magnetic field in the same direction as the traveling direction of a light beam is applied vertically to a light entrance/exit plane of a Faraday rotator by a permanent magnet, and a light transmission region is completely contained in, for example, a region of a magnetic domain A, and emits a light beam without attenuation. When power is applied to an electromagnet to cause a region of the magnetic domain A and a region of a magnetic domain B to substantially equally exist in the light transmission region, a Faraday rotation angle &thgr;f becomes 0°. When a further large current is made to flow to the electromagnet, the light transmission region is completely contained in the region of the magnetic domain B.
    Type: Application
    Filed: August 1, 2003
    Publication date: February 12, 2004
    Applicant: TDK Corporation
    Inventor: Shinji Iwatsuka
  • Patent number: 6673146
    Abstract: A method of manufacturing is used to manufacture a magnet-free Faraday rotator having a square hysteresis loop, the Faraday rotator being formed of a bismuth-substituted rare earth iron garnet single crystal that has a compensation temperature in the range of 10 to 40° C. and is grown on a non-magnetic garnet substrate by a liquid phase epitaxy. The method comprising the steps of placing the bismuth-substituted rare earth iron garnet single crystal film in an environment of a temperature at least 20° C. away from the compensation temperature; and applying an external magnetic field higher than 1000 Oe to the bismuth-substituted rare earth iron garnet single crystal film so that the bismuth-substituted rare earth iron garnet single crystal film is magnetized to have a square hysteresis loop.
    Type: Grant
    Filed: March 27, 2002
    Date of Patent: January 6, 2004
    Assignee: Photocrystal, Inc.
    Inventors: Kazushi Shirai, Norio Takeda
  • Patent number: 6661560
    Abstract: A magneto-optic modulator modulates signals from a superconducting circuit such as a single-flux-quantum (SFQ) logic system onto a carrier wave light beam. The modulator is formed by depositing a magneto-optic material such as EuSe onto a superconducting ground plane such as that of the circuit. A microwave microstrip line is formed on the magneto-optic material and carries a signal from the circuit. The signal induces an H field in the magneto-optic material which causes the magneto-optic material to modulate the light.
    Type: Grant
    Filed: August 24, 2001
    Date of Patent: December 9, 2003
    Assignee: University of Rochester
    Inventor: Roman Sobolewski
  • Publication number: 20030210451
    Abstract: An apparatus which attenuates a light signal polarized in a first direction. The apparatus includes a polarization rotation unit and an output unit. The polarization rotation unit rotates the polarization of the light signal to produce a polarization rotated light signal having a polarization component in the first direction and a polarization component in a second direction which is substantially 90 degrees with respect to the first direction. The output unit passes, as an output signal, the polarization component in the second direction of the polarization rotated light signal and blocks the polarization component in the first direction. The polarization rotation unit includes an electromagnet and a permanent magnet which apply magnetic fields in specific directions with respect to the light path. Various yoke constructions are provided for the electromagnet and the permanent magnet.
    Type: Application
    Filed: April 11, 2003
    Publication date: November 13, 2003
    Applicant: Fujitsu Limited
    Inventors: Hiroshi Onaka, Nobuhiro Fukushima
  • Patent number: 6646777
    Abstract: An optical isolator includes a first magnetic polar source having a first magnet axis, a second magnetic polar source having a second magnet axis parallel to the first magnet axis, and an optical element between the first and second magnetic polar sources, and having a length along the first magnet axis that is less than a length of the first magnetic polar source along the first magnet axis. The optical element has a central axis that is tilted with respect to the second magnet axis.
    Type: Grant
    Filed: February 27, 2002
    Date of Patent: November 11, 2003
    Assignee: JDS Uniphase Corporation
    Inventors: Wenhong Qin, Robert K. Wolf
  • Patent number: 6625378
    Abstract: A variable optical attenuator device is provided for modulating an optical signal. The attenuator device includes a variable attenuation assembly with an electrochromic structure interposed between a first electrode and a second electrode. The electrochromic structure is configured to reversibly change its optical characteristics from a bleached off state to a colored active state under the influence of an electrical potential applied to the first and second electrodes to thereby modulate the optical signal. The optical attenuator device includes at least one lens attached to the variable attenuation assembly. The lens cooperates with the variable attenuation assembly to direct the optical signal towards the electrochromic structure. Waveguides such as optical fibers define ports at the outer endface of the lens for the optical signal.
    Type: Grant
    Filed: October 5, 2001
    Date of Patent: September 23, 2003
    Assignee: JDS Uniphase Corporation
    Inventors: Nada A. O'Brien, J. Gordon H. Mathew, Michael J. Cumbo, Bryant P. Hichwa, Robert W. Adair
  • Patent number: 6618182
    Abstract: In a magneto-optical switching element with a Faraday rotator, in order to increase the switching speed and to reduce the required switching energy respectively, the rotator consists of a magnetically uniaxial crystal, which features magnetic domains of both signs in each of its stable states, by means of which problems are avoided with the creation of domains of opposite signs at the beginning of the switching process.
    Type: Grant
    Filed: March 14, 2002
    Date of Patent: September 9, 2003
    Inventor: Juri S. Didosyan
  • Patent number: 6618183
    Abstract: The method and apparatus for amplitude modulation of unpolarized light by at least one Bragg modulator on the basis of domain-invertible material, the unpolarized light is modulated by a first Bragg modulator both for defining a polarization plane in the unpolarized light and for modulating a light part to be allocated to the polarization plane. A second Bragg modulator is provided which modulates the light part of the unpolarized light allocated to the polarization plane orthogonal to the polarization plane of the first Bragg modulator. The method and apparatus are particularly useful for recording a product to be printed, such as for manufacturing printing forms.
    Type: Grant
    Filed: October 30, 2001
    Date of Patent: September 9, 2003
    Assignee: Heidelberger Druckmaschinen Aktiengesellschaft
    Inventors: Joerg-Achim Fischer, Axel Gebhardt, Peter Ressel
  • Patent number: 6580546
    Abstract: The present invention relates to the use of magnetic materials in combination with magneto-optic materials to improve performance of Faraday rotator devices by enhancing the latching capability and reducing the driving current. Semi-hard magnetic materials are advantageously used in connection with some embodiments of the present invention. Placing such semi-hard magnetic materials in proximity with the magneto-optic material enhances latching and reduces the drive current required to cause switching. Encompassing both the magneto-optic material and the semi-hard magnetic material further reduces drive current requirements and enhances latching by reducing leakage of the magnetic field from its generation within the coil to the magneto-optic material. Some embodiments further include soft or semi-hard material encompassing the coil.
    Type: Grant
    Filed: August 3, 2001
    Date of Patent: June 17, 2003
    Assignee: Primanex
    Inventors: Hongdu Liu, Shizhuo Yin, Daxin Liu, Lee Lisheng Huang
  • Patent number: 6570699
    Abstract: An apparatus which attenuates a light signal polarized in a first direction. The apparatus includes a polarization rotation unit and an output unit. The polarization rotation unit rotates the polarization of the light signal to produce a polarization rotated light signal having a polarization component in the first direction and a polarization component in a second direction which is substantially 90 degrees with respect to the first direction. The output unit passes, as an output signal, the polarization component in the second direction of the polarization rotated light signal and blocks the polarization component in the first direction. The polarization rotation unit includes an electromagnet and a permanent magnet which apply magnetic fields in specific directions with respect to the light path. Various yoke constructions are provided for the electromagnet and the permanent magnet.
    Type: Grant
    Filed: August 6, 2001
    Date of Patent: May 27, 2003
    Assignee: Fujitsu Limited
    Inventors: Hiroshi Onaka, Nobuhiro Fukushima
  • Patent number: 5125408
    Abstract: A biological implantable pressure sensor element comprises a fixed volume pouch formed by a sealed, flexible, impermeable membrane comprising therewithin a gel mass contained in a gel volume, said gel being hydrated with an aqueous solution comprising an agent having at least a first and a second NMR-detectable form, the proportion of the first to the second form of the agent in the gel volume being determined by their electrolytic interaction with the gel, whereby when an external pressure is applied to the sensor element a d (chemical shift)/d(.sigma./K) greater than 0.0001 ppm is attained, wherein .sigma. is the external pressure and K is the modulus of the gel. A kit contains sterile, individually wrapped sensor elements.
    Type: Grant
    Filed: September 19, 1991
    Date of Patent: June 30, 1992
    Assignee: The United States of America as represented by the of the Department of Health and Human Services
    Inventor: Peter J. Basser