Using More Than One Polarization (e.g., Digital) Patents (Class 359/303)
  • Patent number: 10422956
    Abstract: There is provided an integration-type optical modulation device which performs polarization-beam-combining on two linearly polarized light beams respectively output from a plurality of optical modulation elements and outputs the resultant beam so as to seek an improvement and stabilization of optical characteristics, miniaturization, and low cost.
    Type: Grant
    Filed: March 24, 2017
    Date of Patent: September 24, 2019
    Assignee: SUMITOMO OSAKA CEMENT CO., LTD.
    Inventors: Hara Tokutaka, Ryo Shimizu
  • Patent number: 9239348
    Abstract: In an optical modulator directional measurement system embodiment, one or more modulation waves may be measured and directionally discriminated by measuring the modulations of one or more lightwaves. The optical modulator transmission function magnitude for a most phase-matched modulation may be substantially greater than that for other modulations. At sufficiently high modulation frequency, the most phase-matched modulation magnitude may be substantially greater than the other modulation magnitudes. Accordingly, a modulation wave may be distinctly measured by measuring the modulation of the most phase-matched lightwave.
    Type: Grant
    Filed: March 14, 2013
    Date of Patent: January 19, 2016
    Inventor: Kirk S. Giboney
  • Patent number: 8941519
    Abstract: A light intensity subtractor according to one aspect of the present invention includes a light subtraction unit, a feedback circuit, a light input port, a first light output port, and a second light output port. The light subtraction unit receives input light through the light input port, outputs first output light to the first light output port, and outputs second output light to the second light output port. The light subtraction unit generates the first output light by reducing the light intensity of the second output light from the light intensity of the input light in accordance with a control voltage. The feedback circuit is connected to the light subtraction unit through the second light output port, and outputs the control voltage in accordance with the light intensity of the received second output light.
    Type: Grant
    Filed: November 18, 2011
    Date of Patent: January 27, 2015
    Assignee: NEC Corporation
    Inventor: Kenji Sato
  • Publication number: 20140320952
    Abstract: A head-up display device operated in a vehicle comprises: a first image source disposed under the windshield of the vehicle, which emits a first polarized image light having a first polarization; a light path combining component in front of the first image source, which is for that the first polarized image light firstly goes to the light path combining component and only lets the first polarized image light be through and then the image light goes to the windshield, part of the image light is reflected by the windshield to a driver's eyes; and a second image source inside the vehicle, which emits a second polarized image light having a second polarization and then the image light directly goes to or reflects at least one time to the combining component, continuously to the windshield, and the second polarized image light is partially reflected by the windshield to the eyes.
    Type: Application
    Filed: April 26, 2013
    Publication date: October 30, 2014
    Applicant: National Tsing Hua University
    Inventor: Cheng-Huan Chen
  • Patent number: 8784675
    Abstract: The ferroelectric substrate 11 of ferroelectric crystals, while being supported by the support plate 14 which is thicker than the ferroelectric substrate 11, is integrated with the support plate 14 by letting the junction 13 mediate between one major surface S1A of the ferroelectric substrate 11 and one major surface S1B of the support plate 14, and therefore, it is possible through the flat surface polishing to perform thinning of the ferroelectric substrate 11, namely, the ferroelectric crystals, and as a result, it is possible to obtain the thin periodically poled structure. By the voltage application method, the domain inverted region is formed in the ferroelectric substrate 11 which is made thin.
    Type: Grant
    Filed: August 9, 2011
    Date of Patent: July 22, 2014
    Assignee: Dainippon Screen Mfg. Co. Ltd.
    Inventors: Masahide Okazaki, Toshiaki Suhara
  • Patent number: 8570644
    Abstract: The present invention realizes an enhancement of a fabrication yield and a reduction of a size regarding an optical modulator or an optical device including polarization beam combining means. An optical modulator of the present invention (1) includes: first and second optical modulators (LN optical modulators (101) to (104)) that are formed on a substrate; a polarization beam rotating unit (107) that rotates at least one polarization beam of modulated light beams modulated by the first and second optical modulators; and a polarization beam combining element (110) that is disposed outside the substrate and that combines the polarization beams of the modulated light of which the polarization beams are rotated by the polarization beam rotating unit (107).
    Type: Grant
    Filed: December 25, 2009
    Date of Patent: October 29, 2013
    Assignee: Sumitomo Osaka Cement Co., Ltd.
    Inventor: Hitoshi Oguri
  • Patent number: 8482717
    Abstract: The invention relates to a projection system, comprising a radiation source, an illumination system operable to illuminate a structured mask, and a projection objective for projecting an image of the mask structure onto a light-sensitive substrate, wherein said projection system comprises an optical system comprising an optical axis or a preferred direction given by the direction of a light beam propagating through the optical system; the optical system comprising a temperature compensated polarization-modulating optical element described by coordinates of a coordinate system, wherein one preferred coordinate of the coordinate system is parallel to the optical axis or parallel to said preferred direction; said temperature compensated polarization-modulating optical element comprising a first and a second polarization-modulating optical element, the first and/or the second polarization-modulating optical element comprising solid and/or liquid optically active material and a profile of effective optical thickne
    Type: Grant
    Filed: August 29, 2008
    Date of Patent: July 9, 2013
    Assignee: Carl Zeiss SMT GmbH
    Inventors: Damian Fiolka, Markus Deguenther
  • Patent number: 8432597
    Abstract: According to one embodiment of the present invention a digital micro-mirror device is taught that includes a pixel occupying an area of the device and a hinge coupled to the pixel and positioned such that at least a portion of the hinge falls outside the area of the pixel.
    Type: Grant
    Filed: May 8, 2006
    Date of Patent: April 30, 2013
    Assignee: Texas Instruments Incorporated
    Inventor: Richard L. Knipe
  • Patent number: 8295710
    Abstract: The invention describes a modulator for the quadrature modulation of an optical carrier signal with an I- and a Q-portion, where a first optical multimode interferometer (MMI) splits the optical carrier signal into four branches and that in pairs of branches the I-portion and the Q-portion respectively is modulated with a Mach-Zehnder-Structure and a second optical multimode interferometer (MMI) combines the modulated I-portion and Q-portion again to one quadrature modulated optical output signal (OS).
    Type: Grant
    Filed: July 6, 2009
    Date of Patent: October 23, 2012
    Assignee: Nokia Siemens Networks Oy
    Inventor: Winter Marcus
  • Patent number: 8279379
    Abstract: There is provided a light receiving device including a polarization dispersing section that disperses a polarization direction of incoming light into a plurality of polarization directions, a light collecting section that has a metal pattern shaped like concentric circles on a surface thereof, where the light collecting section collects light that has passed through the polarization dispersing section, and a light receiving section that receives the light collected by the light collecting section. Also provided are a light receiving device manufacturing method and a light receiving method. The light collecting section may have a surface plasmon antenna that has the metal pattern shaped like the concentric circles on a surface thereof, and the light receiving section may receive the light collected toward a center of the concentric circles of the metal pattern of the light collecting section, through a hole at the center of the concentric circles, on a rear side of the light collecting section.
    Type: Grant
    Filed: September 23, 2010
    Date of Patent: October 2, 2012
    Assignee: Advantest Corporation
    Inventors: Shin Masuda, Eiji Kato
  • Publication number: 20120033147
    Abstract: A multi-domain vertical alignment liquid crystal display that does not require physical features on the substrate (such as protrusions and ITO slits) is disclosed. Each pixel of the MVALCD is subdivided into color components, which are further divided into color dots. The polarity of the color dots are arranged so that fringe fields from adjacent color dots causes multiple liquid crystal domains in each color dot. Specifically, the color dots of a pixel are arranged so that each color dot of a first polarity has four neighboring pixels of a second polarity. Thus, a checkerboard pattern of polarities is formed. Furthermore, the checkerboard pattern is extended across multiple pixels in the MVALCD. In addition, many display unit include multiple pixel designs to improve color distribution or electrical distribution.
    Type: Application
    Filed: October 17, 2011
    Publication date: February 9, 2012
    Applicants: Kyoritsu Optronics Co., Ltd.
    Inventor: Hiap L. Ong
  • Patent number: 8080777
    Abstract: Provided is an optical device, comprising a plurality of polarizers that are arranged along a propagation direction of incident light; a first phase element that is disposed between the plurality of polarizers and that has a phase lag axis forming a prescribed angle relative to transmission axes of the polarizers arranged along the propagation direction; and a second phase element that is disposed between the first phase element and one of the polarizers arranged along the propagation direction, and that provides the incident light with a prescribed phase difference. An angle of the phase lag axis of the second phase element is adjusted such that the optical device transmits light in a prescribed wavelength region in the incident light.
    Type: Grant
    Filed: February 11, 2009
    Date of Patent: December 20, 2011
    Assignee: FUJIFILM Corporation
    Inventors: Takashi Murooka, Hideyasu Ishibashi, Ichiro Amimori
  • Publication number: 20110255147
    Abstract: The present invention realizes an enhancement of a fabrication yield and a reduction of a size regarding an optical modulator or an optical device including polarization beam combining means. An optical modulator of the present invention (1) includes: first and second optical modulators (LN optical modulators (101) to (104)) that are formed on a substrate; a polarization beam rotating unit (107) that rotates at least one polarization beam of modulated light beams modulated by the first and second optical modulators; and a polarization beam combining element (110) that is disposed outside the substrate and that combines the polarization beams of the modulated light of which the polarization beams are rotated by the polarization beam rotating unit (107).
    Type: Application
    Filed: December 25, 2009
    Publication date: October 20, 2011
    Applicant: SUMITOMO ASAKA CEMENT CO., LTD.
    Inventor: Hitoshi Oguri
  • Patent number: 7929108
    Abstract: An optical switching device includes an array of liquid crystal macropixels, wherein each macropixel includes at least two liquid crystal subpixels. The subpixels may be controlled together to act as a single polarizing pixel, or independently to act as multiple polarizing pixels. When the switching device processes a WDM having a wide channel spacing, the subpixels are controlled together, and when the switching device processes a WDM having a narrow channel spacing, each subpixel is controlled independently.
    Type: Grant
    Filed: February 15, 2008
    Date of Patent: April 19, 2011
    Assignee: Oclaro (North America), Inc.
    Inventor: Giovanni Barbarossa
  • Patent number: 7898725
    Abstract: A light modulator device includes a first electrical conduit, a second electrical conduit electrically isolated from the first conduit, a first display element, and a second display element. The first display element is in an actuated state when a voltage difference between the first conduit and the second conduit has a magnitude greater than a first actuation voltage and is in a released state when the voltage difference has a magnitude less than a first release voltage. The second display element is in an actuated state when the voltage difference has a magnitude greater than a second actuation voltage and is in a released state when the voltage difference has a magnitude less than a second release voltage. Either the actuation voltages are substantially equal and the release voltages are different, or the actuation voltages are different and the release voltages are substantially equal.
    Type: Grant
    Filed: September 2, 2010
    Date of Patent: March 1, 2011
    Assignee: QUALCOMM MEMS Technologies, Inc.
    Inventor: Jeffrey B. Sampsell
  • Patent number: 7878656
    Abstract: A stereo projection optical system includes a first polarizing beam splitter, a transmission-type light modulator positioned to receive the first polarized light component from the first polarizing light splitter and an image assimilator positioned to receive an emergent light of the transmission-type light modulator. The image assimilator includes a second polarized light splitter and first, second reflective spatial light modulators. The stereo projection optical systems provide viewers three-dimensional images formed by two alternative polarization light beams whose polarizations are perpendicular to each other utilizing the transmission-type light modulators to form “3-D” images.
    Type: Grant
    Filed: December 7, 2007
    Date of Patent: February 1, 2011
    Assignee: Hon Hai Precision Industry Co., Ltd.
    Inventors: Chien-Wen Hsu, Chia-Hung Kao
  • Patent number: 7808695
    Abstract: A light modulator device includes a first electrical conduit, a second electrical conduit electrically isolated from the first conduit, a first display element, and a second display element. The first display element is in an actuated state when a voltage difference between the first conduit and the second conduit has a magnitude greater than a first actuation voltage and is in a released state when the voltage difference has a magnitude less than a first release voltage. The second display element is in an actuated state when the voltage difference has a magnitude greater than a second actuation voltage and is in a released state when the voltage difference has a magnitude less than a second release voltage. Either the actuation voltages are substantially equal and the release voltages are different, or the actuation voltages are different and the release voltages are substantially equal.
    Type: Grant
    Filed: December 29, 2008
    Date of Patent: October 5, 2010
    Assignee: QUALCOMM MEMS Technologies, Inc.
    Inventor: Jeffrey B. Sampsell
  • Patent number: 7798648
    Abstract: An optical path length adjuster enables electro-optical control of a physical path length between two optical elements, suitable for use in the adjustment of an optical path length within three dimensional display devices that generate a virtual image within a defined imaging volume. The adjuster varies an optical path length between an input optical path and an output optical path and includes: a first polarization switch for selecting a polarization state for an input beam on the input optical path; first and second beam splitters having at least two possible optical paths of different lengths therebetween, for passing the input beam along a selected one of said at least two possible optical paths according to the selected polarization state of the input beam and for providing an output beam of light, on said optical output path, that has traveled along the selected optical path.
    Type: Grant
    Filed: January 6, 2005
    Date of Patent: September 21, 2010
    Assignee: Koninklijke Philips Electronics N.V.
    Inventors: Willem L. Ijzerman, Marcellinus P. C. M. Krijn, Bart A. Salters
  • Patent number: 7782517
    Abstract: One inventive aspect relates to a display comprising a display element configured to selectively reflect light of a first wavelength in the infrared range and light of a second wavelength in the visible spectrum. Another inventive aspect relates to a color display comprising at least three reflective display elements. Each display element is configured to selectively reflect light of a different wavelength in the visible range. At least one of the three reflective display element is further configured to selectively reflect light of a wavelength in the infrared range.
    Type: Grant
    Filed: June 21, 2007
    Date of Patent: August 24, 2010
    Assignee: QUALCOMM MEMS Technologies, Inc.
    Inventors: Jonathan Charles Griffiths, Jeffrey B. Sampsell
  • Patent number: 7773288
    Abstract: Provided is a dynamic image regulator. The dynamic image regulator is an application device based on a micro-opto-electro-mechanical system (MOEMS). The dynamic image regulator includes a spatial light modulator comprising a plurality of holes and a plurality of controllable movable screens respectively provided at the holes, and transmitting or blocking emitted light for each respective hole; and an amplitude modulator modulating an amplitude of light passing through the spatial light modulator.
    Type: Grant
    Filed: October 10, 2008
    Date of Patent: August 10, 2010
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Oleg Borisovich Danilov, Aleksander Ivanovich Sidorov, Olga Petrovna Vinogradova
  • Patent number: 7733558
    Abstract: A display device implemented with a spatial light modulator (SLM) comprising a plurality of pixel elements arranged in array to modulate incident light and display an image, wherein each of the pixel elements comprises a movable electrode and a stationary electrode; a drive circuit connected to the movable electrode and receives image data for applying a voltage applied to control the movable electrode in accordance with image data, and a voltage application circuit for applying and controlling a voltage applied to the stationary electrode to control a moving speed of the movable electrode.
    Type: Grant
    Filed: March 25, 2009
    Date of Patent: June 8, 2010
    Assignees: Silicon Quest Kabushiki-Kaisha, Olympus Corporation
    Inventors: Kazuma Arai, Yoshihiro Maeda, Naoya Sugimoto, Fusao Ishii
  • Patent number: 7649676
    Abstract: A system and method are used to form an unpolarized light beam from a polarized light beam. A system comprises a source of radiation and a unpolarizing system. The source of radiation produces a linear polarized beam. The unpolarizing system has first and second optical paths and splits the linear polarized beam. A first portion of the split beam travels along the first optical path having a first path length. A second portion of the split beam travels along the second optical path having a second, different path length. The first and second portions of the split beam are combined to form the unpolarized beam.
    Type: Grant
    Filed: June 14, 2006
    Date of Patent: January 19, 2010
    Assignee: ASML Netherlands B.V.
    Inventors: Johannes Jacobus Matheus Baselmans, Huibert Visser
  • Publication number: 20090195860
    Abstract: An optical modulator includes, a first polarization separation and combination portion, a second polarization separation and combination portion, a first polarization plane-maintaining optical fiber, a second polarization plane-maintaining optical fiber, a third polarization plane-maintaining optical fiber of which a first end is coupled with the second input and output terminal of the second polarization separation and combination portion, the third polarization plane-maintaining optical fiber including a first optical coupler, to which control light that is linearly polarized light is input, a fourth polarization plane-maintaining optical fiber of which a first end is coupled with the third input and output terminal of the second polarization separation and combination portion; and a first polarization plane conversion portion that optically communicates with a second end of the third polarization plane-maintaining optical fiber and a second end of the fourth polarization plane-maintaining optical fiber.
    Type: Application
    Filed: November 6, 2008
    Publication date: August 6, 2009
    Applicant: Oki Electric Industry Co., Ltd.
    Inventors: Shin Arahira, Hitoshi Murai
  • Publication number: 20090021824
    Abstract: An optical path length adjuster enables electro-optical control of a physical path length between two optical elements, suitable for use in the adjustment of an optical path length within three dimensional display devices that generate a virtual image within a defined imaging volume. The adjuster varies an optical path length between an input optical path and an output optical path and includes: a first polarisation switch for selecting a polarisation state for an input beam on the input optical path; first and second beam splitters having at least two possible optical paths of different lengths therebetween, for passing the input beam along a selected one of said at least two possible optical paths according to the selected polarisation state of the input beam and for providing an output beam of light, on said optical output path, that has traveled along the selected optical path.
    Type: Application
    Filed: January 6, 2005
    Publication date: January 22, 2009
    Applicant: KONINKLIJKE PHILIPS ELECTRONIC, N.V.
    Inventors: Willem L. Ijzerman, Marcellinus P.C.M. Krijn, Bart A. Salters
  • Publication number: 20080316585
    Abstract: A fiber-optical, wavelength selective switch, especially for channel routing with equalization and blocking applications. The input signals are converted to light beams having predefined polarizations (41). The beams are then laterally expanded (43), and then undergo spatial dispersion in the beam expansion plane. The different wavelength components are directed through a polarization rotation device, pixilated along the wavelength dispersion direction such that each pixel operates on a separate wavelength. Each beam is passed into a pixilated beam steering array (48), for directing each wavelength to a desired output port. The beam steering devices can be MEMS-based or Liquid crystal-based, or an LCOS array. When the appropriate voltage is applied to a pixel and its associated beam steering element, the polarization of the light passing through the pixel is rotated and the beam steered to couple to the selected output port.
    Type: Application
    Filed: September 10, 2006
    Publication date: December 25, 2008
    Applicant: XTELLUS, INC.
    Inventors: Gil Cohen, SeongWoo Suh, Yossi Corem
  • 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: 7149028
    Abstract: The present invention provides a transmissive-diffractive light modulator in which a substrate having the same structure as that of a conventional diffractive light modulator has a light transmittance gate or is made of a transparent material, thus diffracting incident light while the incident light passes through the substrate.
    Type: Grant
    Filed: September 28, 2004
    Date of Patent: December 12, 2006
    Assignee: Samsung Electro-Mechanics Co., Ltd.
    Inventor: Sang Kyeong Yun
  • Patent number: 7126741
    Abstract: A light modulator assembly includes a substrate, a micro-electro mechanical semiconductor device (MEMS device) formed on the substrate, and a temperature control device coupled to the substrate and configured to maintain the MEMS device at or above an elevated threshold temperature.
    Type: Grant
    Filed: August 12, 2004
    Date of Patent: October 24, 2006
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: William R. Wagner, Winthrop D. Childers
  • Patent number: 7099064
    Abstract: Disclosed herein are an electrostatic-type variable diffractive light modulator, which includes lower micromirrors that are provided on a glass substrate to be spaced apart from each other, and actuates upper micromirrors that are spaced apart from the substrate by an electrostatic actuating method, thus allowing the upper and lower micromirrors to diffract incident light entering a lower portion of the substrate, and a method of manufacturing the electrostatic-type variable diffractive light modulator.
    Type: Grant
    Filed: September 28, 2004
    Date of Patent: August 29, 2006
    Assignee: Samsung Electro-Mechanics Co., Ltd.
    Inventors: Yoon-Shik Hong, Dong-Ho Shin, Jong-Hyeong Song, Yoon-Joon Choi, Yurlov Victor
  • 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: 6690346
    Abstract: An image display capable of effectively preventing deterioration of the contrast and permitting sufficient resolution improvement to be obtained by wobbling is disclosed. A display element 1 has a display surface with a regular array of a plurality of pixels. A vibrating means 2, 3 or 21 vibrates the optical axis of the light beam emitted from the display surface in predetermined directions. An image display control means 11 causes display of different images on the display element 1 in synchronism to vibrations of the optical axis caused by the vibrating means. The vibrating means includes a polarization conversion control means 2 and 22 to 25 capable of controlling the polarization conversion timing.
    Type: Grant
    Filed: April 13, 1999
    Date of Patent: February 10, 2004
    Assignee: Olympus Corporation
    Inventor: Kazunari Hanano
  • Publication number: 20020080467
    Abstract: A polarization mode dispersion generator for generating polarization mode dispersion (“PMD”) spectra is provided. The generator includes a plurality of birefringent stages, each stage including a differential group delay (“DGD”) element and a phase-shifting element. The generator is capable of inducing an amount of polarization mode-mixing between at least one adjacent pair of stages. The shape of a PMD spectrum can be preserved while frequency shifting the spectrum in either direction. Alternatively, the shape of the PMD spectrum can be changed without frequency shifting.
    Type: Application
    Filed: December 7, 2001
    Publication date: June 27, 2002
    Applicant: Yafo Networks, Inc.
    Inventor: Jay N. Damask
  • Patent number: 6061103
    Abstract: An image display apparatus for use in head-mounted image display apparatus is disclosed. The apparatus comprises an image display element having a plurality of pixels arrayed in matrix, for displaying images by scanning these pixels with image signals; a pixel shifting means provided so as to divide these image display elements into a plurality of regions in a direction orthogonal to the scanning direction of the image signal, for selectively shifting viewing positions of the displayed images in respective regions; and a control means for controlling shifting operation at the viewing positions of the displayed images in corresponding regions of the pixel shifting means, in synchronism with the scanning of the image display elements.
    Type: Grant
    Filed: January 22, 1996
    Date of Patent: May 9, 2000
    Assignee: Olympus Optical Co., Ltd.
    Inventors: Toshiro Okamura, Seiichiro Tabata
  • Patent number: 5963291
    Abstract: An optical power regulator employs a variable optical attenuator having a first birefringent element that spatially separates the input optical beam into two orthogonally-polarized beams. Both beams pass through a polarization modulator (e.g., a liquid crystal material) that rotates their polarizations to an extent determined by the control voltage applied across the polarization modulator. A final birefringent element spatially separates both beams exiting the polarization modulator into two pairs of orthogonally-polarized beams (i.e., two horizontally-polarized and two vertically-polarized components). The thicknesses and optical properties of the birefringent elements are selected so that two of the four beams are combined by the final birefringent element to exit at the output port of the regulator, while the remaining two beams are blocked.
    Type: Grant
    Filed: July 21, 1997
    Date of Patent: October 5, 1999
    Assignee: Chorum Technologies Inc.
    Inventors: Kuang-Yi Wu, Jian-Yu Liu, Yen-Chen Chen
  • Patent number: 5930028
    Abstract: A split reciprocal polarization switch (SRPS) for use in constructing high performance switching devices used in fiber optics. The SRPS allows selective changes in the polarization of one or the other of two optical rays passing therethrough along first and second bi-directional ray paths of the SRPS so that they emerge therefrom with the same polarizations. The SRPS includes a switching section for selectively changing the optical polarization of optical rays according to a selected state of the switching section, and a split section including a first and second sections having different polarization changing characteristics.
    Type: Grant
    Filed: May 21, 1998
    Date of Patent: July 27, 1999
    Assignee: Lucent Technologies Inc.
    Inventor: Ernest Eisenhardt Bergmann
  • Patent number: 5729380
    Abstract: A loop four-wave mixing phase conjugator that can be used with depolarized signal beams comprises a polarization separator, a polarization mixer, an optical diode, a gain medium and relay optics that together form a unidirectional laser resonator. In operation, the polarization separator separates a signal beam .epsilon..sub.1 into orthogonally polarized signal beam components .epsilon..sub.11 and .epsilon..sub.12 and directs them to a nonlinear medium. The components propagate through the nonlinear medium and emerge as loop beam .epsilon..sub.2, with orthogonally polarized components .epsilon..sub.2 and .epsilon..sub.22. The polarization mixer mixes the energy from the two orthogonally polarized loop beam components, and relay optics direct the loop beam components back to the nonlinear medium at an angle with respect to the input beam. The loop beam components intersect and optically interfere with signal beam components .epsilon..sub.11 and .epsilon..sub.22 in the nonlinear medium to form gratings.
    Type: Grant
    Filed: October 30, 1996
    Date of Patent: March 17, 1998
    Assignee: Hughes Electronics
    Inventors: Alexander A. Betin, Metin S. Mangir
  • Patent number: 5548427
    Abstract: A switchable holographic device which includes a first polarizer having a spatially varying direction of polarization. The device also includes a liquid crystal device arranged to act as a controllable phase plate, the liquid crystal device having a predetermined phase shift in one state and substantially no birefringent activity in another state. The liquid crystal device is thus controllable to selectively alter the polarization of at least some of the radiation passing therethrough or to have substantially no optical activity. An output polarizer receives the radiation from the liquid crystal device so that, depending on the state of the liquid crystal device, the hologram is replayed or not replayed.
    Type: Grant
    Filed: January 20, 1995
    Date of Patent: August 20, 1996
    Assignee: Sharp Kabushiki Kaisha
    Inventor: Paul May
  • Patent number: 5537256
    Abstract: An electronic dithering system based on birefringence or double refraction increases the resolution of a display and includes a birefringent material, such as a calcite material, which selectively refracts or deflects light depending on an optical polarization characteristic of the light, and a switch to switch the optical polarization characteristic of the light, thereby to determine the location of output optical information. Thus, the apparatus and method of the invention can change the location of an optical signal, and the change can be used for a number of purposes, such as to improve resolution of a display, to provide an auto-stereoscopic output, to interlace optical signals, to facilitate locating and hiding of circuitry, to facilitate overlapping of tiles or pixels, etc.
    Type: Grant
    Filed: October 25, 1994
    Date of Patent: July 16, 1996
    Inventor: James L. Fergason
  • Patent number: 5497437
    Abstract: There is provided a method for modulating the polarization of light that allows detection of any modulated output regardless if the optical analyzers are rigidly held in place. According to a first aspect of the invention, a method for receiving light with a modulated polarization comprises steps of dividing the light being propagated through an optical fiber 1 with a polarization modulated in accordance with a modulation signal into three branched beams, causing one of the branched beams of light with a modulated polarization to pass through a .pi./2 phase corrector 2 and a first optical analyzer 3a and causing the remaining branched beams of light to respectively pass through second and third optical analyzers 3b and 3c without passing through any .pi./2 phase correctors before in order to receive light with a modualted intensity from the optical analyzers 3a, 3b and 3c.
    Type: Grant
    Filed: December 6, 1994
    Date of Patent: March 5, 1996
    Assignee: The Furukawa Electric Co., Ltd.
    Inventors: Toshiya Hikami, Shoichi Negami, Shigeaki Nishikawa, Matsue Murata
  • Patent number: 5477350
    Abstract: An interferometric switch for spatially switching either linearly polarized or unpolarized externally derived beams of substantially coherent light includes an optical input unit for dividing an externally derived light beam into a constituent beam pair. An optical phase modulating device includes a nematic liquid crystal pixel for selectively shifting the relative phase of the constituent beam pair. An output unit cooperates to combine respective components of the constituent beam pair along coincident collinear paths so as to form a respective output light beam directed along a selected one of first and second output axes, according to the relative phase imparted by the phase-modulating device. The phase modulating device may comprise a cascading arrangement of pixel stages which can respectively provide a selected incremental phase-shift to each constituent beam passing therethrough.
    Type: Grant
    Filed: June 1, 1993
    Date of Patent: December 19, 1995
    Assignee: General Electric Company
    Inventors: Nabeel A. Riza, Donald E. Castleberry, Thomas L. Credelle, Michael C. DeJule
  • Patent number: 5212587
    Abstract: A binary tree switching network in which the switching states are configured to switch an input signal from a selected input to an output by means of a control code set having a minimum Hamming distance (d) greater than one which eliminates cross-talk of order (d-1) and less. Such a network may be used for switching optical signals by means of optical beam deflector stages, each having a variable polarization rotator and a polarization sensitive deflector. Elimination of first order cross-talk is readily achieved by a modification stage arranged to receive a single input from the preceding stages and to pass it to the output.
    Type: Grant
    Filed: December 27, 1990
    Date of Patent: May 18, 1993
    Assignee: British Telecommunications plc
    Inventor: Peter Healey