Acousto-optic Patents (Class 359/285)
  • Patent number: 6718076
    Abstract: An acousto-optic tunable filter that includes a polarization beamsplitter, a multi-segment interaction region and a polarization beam combiner is described. The polarization beamsplitter generates a first and a second polarized optical signal. The multi-segment optical interaction region includes a first optical interaction region and a first acoustic wave generator that generates acoustic waves in the first optical interaction region. The multi-segment optical interaction region also includes a second optical interaction region that is non-collinear relative to the first optical interaction region and a second acoustic wave generator that generates acoustic waves in the second optical interaction region. Optical signals that are phase-matched to the acoustic waves are mode-converted in response to the acoustic waves. The acousto-optic tunable filter also includes a polarization beam combiner that generates both a mode-converted optical signal and a non-mode-converted optical signal.
    Type: Grant
    Filed: March 22, 2002
    Date of Patent: April 6, 2004
    Assignee: Unaxis USA, Inc.
    Inventors: Kenneth J. Bures, Dogan Gunes, Chunghsin Lee, Paul Maki, Piero Sferlazzo
  • Publication number: 20040012837
    Abstract: The invention concerns a device comprising a birefringent elasto-optic medium (1) equipped with a transducer (5) generating in the medium (1) a modulated acoustic wave along a specific direction, and means for coupling in the medium (1) an input optical wave with unknown polarisation, and a programming circuit for (amplitude-phase-frequency) modulation of the acoustic wave. Said device supplies a direct wave and two perpendicular diffracted waves of H, V polarisation each bearing a modulation based on the input optical wave modulation and the acoustic wave modulation.
    Type: Application
    Filed: July 3, 2003
    Publication date: January 22, 2004
    Inventors: Daniel Kaplan, Thomas Oksenhendler, Pierre Tournois
  • Patent number: 6665112
    Abstract: An optical reticle substrate inspection apparatus is provided with a laser, a first acoustooptical element which scans a laser beam output from the laser, an a second acoustooptical element which generates a virtual image with a concave lens effect to the laser beam output from the first acoustooptical element. The optical reticle substrate inspection apparatus is further provided with a concave lens arranged on the output side of the laser beam of the second acoustooptical element and an optical system which images the virtual image on a reticle substrate being an object to be inspected. The concave lens magnifies the laser beam in a perpendicular direction to the scanning direction by the first acoustooptical element.
    Type: Grant
    Filed: February 4, 2003
    Date of Patent: December 16, 2003
    Assignee: NEC Corporation
    Inventor: Motonari Tateno
  • Patent number: 6657222
    Abstract: A photon source, comprising a first semiconductor region having excess carriers with a first conductivity type, and a second semiconductor region having excess carriers with a second conductivity type, the first and second conductivity types being opposing conductivity types; means for creating a surface acoustic wave (SAW) travelling from the first semiconductor region to the second semiconductor region such that excess carriers from the first semiconductor region are carried by the wave to the second region and quantizing means for quantizing the carrier transport caused by the wave, such that the number of carriers introduced into the second semiconductor region can be controlled to the accuracy of a single carrier.
    Type: Grant
    Filed: September 14, 2000
    Date of Patent: December 2, 2003
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Clare Louise Foden, Mark Levence Leadbeater, Valery Talyansky
  • Patent number: 6654127
    Abstract: One embodiment of the present invention is an optical delay line that comprises a plurality of optical elements in optical communication with each other, wherein: (a) at least one of the plurality of optical elements is capable of spatially dispersing a spectrum of an optical signal to provide a spatially dispersed optical signal; (b) at least one of the plurality of optical elements is adjustable to affect one or more of a phase delay and a group delay of an optical signal; and (c) at least one of the plurality of optical elements compensates for polarization introduced into the optical signal by others of the optical elements.
    Type: Grant
    Filed: March 1, 2001
    Date of Patent: November 25, 2003
    Assignee: Carl Zeiss Ophthalmic Systems, Inc.
    Inventors: Matt J. Everett, Jay Wei
  • Patent number: 6647196
    Abstract: An electro-acoustic transducer is attached to a block of optical material, and forms an acoustic standing wave in the block; the acoustic standing wave periodically changes the refractive index of the optical material, and forms high refractive index portions alternated with low refractive index portions; and the high refractive index portions serve as optical wave guides, and the electro-acoustic transducer easily produces the optical wave guide in the block.
    Type: Grant
    Filed: December 9, 1998
    Date of Patent: November 11, 2003
    Assignee: NEC Corporation
    Inventor: Hikaru Kouta
  • Publication number: 20030206327
    Abstract: The disclosed invention provides a variable lenslet array system that comprises an acousto-optic medium and at least one acoustic wave generator that is positioned adjacent to the acousto-optic medium. The acoustic wave generator is adapted to generate standing acoustic waves into the acousto-optic medium. The wavelength of the resonant acoustic waves is variable in respect to the medium dimensions or can be varied by changing the driving frequency of the wave generator. The standing acoustic waves within the acousto-optic medium change locally the index of refraction. A wave front of a light beam, which crosses these periodic changes of the index of refraction, becomes corrugated and effectively, an array of lenslets is formed.
    Type: Application
    Filed: May 3, 2002
    Publication date: November 6, 2003
    Inventor: Erez N. Ribak
  • Patent number: 6628451
    Abstract: A product and method uses acousto-optic reflection-active media having an optical reflectivity which changes with changes in acoustic energy intensity interacting with the media to form images of defects in samples when the defects reflect acoustic energy differently from known acoustically reflecting parts of the samples.
    Type: Grant
    Filed: February 14, 2002
    Date of Patent: September 30, 2003
    Inventors: Jaswinder S Sandhu, Honghui Wang
  • Patent number: 6624889
    Abstract: An optical channel monitor (OCM) or filter for analyzing an incident light carrying a number of narrow band signal channels such as WDM or DWDM channels. The OCM or filter use an acousto-optic tunable filter to receive and refract from an incident light a refracted light such that the refracted light contains a test channel with a center frequency &ngr;0. A first birefringent element is provided for filtering from the refracted light a first polarized light and a second polarized light orthogonal to the first polarized light. The transmission curves are engineered such that the transmissions of the first and second polarized light are substantially equal at the center frequency &ngr;0 of the test channel. The OCM or filter has a second birefringent element for filtering from the first polarized light a first polarized portion and a second polarized portion.
    Type: Grant
    Filed: April 29, 2002
    Date of Patent: September 23, 2003
    Assignee: Oplink Communications, Inc.
    Inventor: Shifang Li
  • Publication number: 20030151794
    Abstract: A product and method uses acousto-optic reflection-active media having an optical reflectivity which changes with changes in acoustic energy intensity interacting with the media to form images of defects in samples when the defects reflect acoustic energy differently from known acoustically reflecting parts of the samples.
    Type: Application
    Filed: February 14, 2002
    Publication date: August 14, 2003
    Inventors: Jaswinder S. Sandhu, Honghui Wang
  • Patent number: 6600590
    Abstract: A system and method for reducing or eliminating the speckle intensity distribution of a laser imaging system. In one embodiment of the invention, a radio frequency signal is injected into a semiconductor laser light source (12) for a projection system (10) to create different speckle patterns that blend together on a projection surface (19). In another embodiment of the invention, optical feedback is used to induce a laser light source for a projection system (10) to create different speckle patterns that blend together on a projection surface (19). In another embodiment of the invention, the laser light source wavelength is Doppler shifted to produce different speckle patterns. In another embodiment of the invention, a means of deflection is used to directionally move the beam to reduce noticeable speckle.
    Type: Grant
    Filed: February 20, 2001
    Date of Patent: July 29, 2003
    Assignee: Eastman Kodak Company
    Inventors: James E. Roddy, William R. Markis
  • Patent number: 6587255
    Abstract: An acousto-optic scanning system, which relies on two counter propagating acoustic waves with the same frequency modulation. This scheme completely suppresses the linear frequency chirp, and thus enables the generation of fast non-linear scans and non-constant linear scans. By changing the phase between the modulating signals, this scheme also provides fast longitudinal scans of the focal point.
    Type: Grant
    Filed: December 13, 2001
    Date of Patent: July 1, 2003
    Assignee: Yeda Research and Development Co.LTD
    Inventors: Nir Davidson, Nir Friedman, Ariel Kaplan
  • Patent number: 6555781
    Abstract: A method and apparatus for precision laser scanning suitable for precision machining or cleaning using an ultrashort pulsed laser beam are disclosed. The apparatus employs a laser source that emits a pulsed laser beam, a dispersion compensation scanner that scans the pulsed laser beam, and a focusing unit that focuses the pulsed laser beam from the dispersion compensation scanner on a work piece. The dispersion compensation scanner comprises a first scanning device that scans the pulsed laser beam in a first direction and that causes dispersion of the pulsed laser beam. The dispersion compensation scanner further comprises a first dispersion compensation device that compensates for the dispersion caused by the first scanning device. Effects of polarization of the ultrashort pulsed laser beam on the quality of machining are described. Uses of the invention in direct fabrication of photolithographic masks and in work piece cleaning are also described.
    Type: Grant
    Filed: July 5, 2001
    Date of Patent: April 29, 2003
    Assignee: Nanyang Technological University
    Inventors: Bryan Kok Ann Ngoi, Krishnan Venkatakrishnan
  • Patent number: 6549247
    Abstract: An ultrasonic liquid-crystal display comprises a nonpiezoelectric bottom-plate, a piezoelectric substrate on a first surface-part of an upper end-surface of the nonpiezoelectric bottom-plate, at least one dispersive interdigital transducer on the piezoelectric substrate, a nonpiezoelectric upper-plate, a first conducting electrode, with which a second surface-part of the upper end-surface of the nonpiezoelectric bottom-plate is covered, a second conducting electrode, with which a lower end-surface of the nonpiezoelectric upper-plate is covered, and a liquid crystal between the first- and second conducting electrodes. The nonpiezoelectric bottom-plate and the nonpiezoelectric upper-plate have a transparency, respectively. When a first electric signal is applied to the dispersive interdigital transducer, an FM chirp-SAW is excited in the piezoelectric substrate. The FM chirp-SAW transmitted to the liquid crystal causes it cloudy.
    Type: Grant
    Filed: March 6, 2001
    Date of Patent: April 15, 2003
    Inventor: Kohji Toda
  • Patent number: 6538795
    Abstract: An optical reticle substrate inspection apparatus is provided with a laser, a first acoustooptical element which scans a laser beam output from the laser, and a second acoustooptical element which generates a virtual image with a concave lens effect to the laser beam output from the first acoustooptical element. The optical reticle substrate inspection apparatus is further provided with a concave lens arranged on the output side of the laser beam of the second acoustooptical element and an optical system which images the virtual image on a reticle substrate being an object to be inspected. The concave lens magnifies the laser beam in a perpendicular direction to the scanning direction by the first acoustooptical element.
    Type: Grant
    Filed: November 29, 2001
    Date of Patent: March 25, 2003
    Assignee: NEC Corporation
    Inventor: Motonari Tateno
  • Patent number: 6532097
    Abstract: An image registration apparatus has a substrate support capable of supporting a substrate, the substrate support having a support motor capable of moving the substrate support. A radiation beam source is provided that is capable of providing a radiation beam. A beam intensity modulator is also provided that has an adjustable reflective diffraction grating capable of reflectively diffracting the radiation beam to modulate the intensity of the radiation beam. A controller is also provided that is adapted to control the substrate support, radiation beam source, and beam intensity modulator to modulate and scan the radiation beam across the substrate to register an image on the substrate.
    Type: Grant
    Filed: October 11, 2001
    Date of Patent: March 11, 2003
    Assignee: Applied Materials, Inc.
    Inventors: Paul C. Allen, Samuel C. Howells
  • Patent number: 6528937
    Abstract: A display device has a light source and a display part including a light guide, a movable element, and selection means to locally and selectively bring the movable element into contact with the light guide to couple light out of the light guide. The light source is a UV radiation source. The movable element includes means for scattering UV light. The display device includes phosphor elements for emitting visible light at different colors when excited by UV radiation. The phosphor elements include phosphor particles in an embedding material.
    Type: Grant
    Filed: February 22, 2000
    Date of Patent: March 4, 2003
    Assignee: Koninklijke Philips Electronics N.V.
    Inventor: Gerardus G. P. Van Gorkom
  • Publication number: 20030007712
    Abstract: A diffraction-optical component for providing a radiation-diffracting grating structure is proposed, comprising a surface wave device including a substrate 43, a surface wave source 47 excitable with an adjustable frequency for producing surface waves on a surface 45 of the substrate 43 and an interaction region 17 of the substrate surface 45 which is provided for the radiation to interact with a grating structure provided by the surface waves produced.
    Type: Application
    Filed: March 20, 2002
    Publication date: January 9, 2003
    Inventors: Martin Ross-Messemer, Alexander Menck, Frank Holler, Kurt Franke, Gunter Martin, Hagen Schmidt, Manfred Weihnacht
  • Publication number: 20030002129
    Abstract: An optical acoustoelectric transducer having a directivity pattern like a better 8 by receiving by a light-receiving element a reflected fraction of the light from a light-emitting device disposed at the center of a bottom plate that is parallel to a diaphragm, has an opening through which an acoustic wave enters, and is connected to supporting side plates. An optical acoustoelectric transducer having uniform amplitude characteristics in a wide frequency range by mixing by a mixer circuit the outputs of a plurality of optical microphones having diaphragms of mutually different thicknesses so as to make the receiving sensitivity uniform in different frequency ranges. A directional optical acoustoelectric transducer having a small size and wide band characteristics by arranging a plurality of light-emitting devices (LD) and a plurality of light-receiving elements (PD) corresponding to a plurality of diaphragms arranged parallel.
    Type: Application
    Filed: June 7, 2002
    Publication date: January 2, 2003
    Inventors: Okihiro Kobayashi, Nobuhiro Miyahara, Yutaka Hattori, Hiroshi Miyazawa, Junichi Hayakawa
  • Patent number: 6490075
    Abstract: The present invention has applications that include detecting color variation in a region, for example, color variations due to temperature changes in an area of ocean water, and, in a more specific application, detecting bioluminescence of certain organisms known to attach themselves to various objects. In one aspect of the invention, an acousto-optic tunable filter hyperspectral imaging system is moved across the region to collect a series of images in which each image represents the intensity of light at a different wavelength. In one embodiment, the acousto-optic tunable filter hyperspectral imaging system includes a motion platform for positioning the acousto-optic tunable filter hyperspectral imaging system over successive Y-coordinates of a region in a direction substantially parallel to a direction of motion of the motion platform.
    Type: Grant
    Filed: August 16, 2001
    Date of Patent: December 3, 2002
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventors: Richard Scheps, Jon S. Schoonmaker
  • Patent number: 6466705
    Abstract: An acousto-optic variable-wavelength TE/TM mode converter is configured by comprising an optical waveguide, a coupled acoustic waveguide composed of two acoustic waveguides, comb electrodes arranged at the acoustic waveguides, and surface acoustic wave absorbers arranged at the acoustic waveguide. If high-frequency electric signals having different frequencies are applied to the electrodes, surface acoustic waves W11 and W12 occur on the surface of the piezoelectric substrate, meander and propagate in the substrate, and are finally absorbed by the absorbers. The intensity distributions of the surface acoustic waves W11 and W12 are distributions where the intensity is high in a middle portion of the optical guide, and low at both ends of the optical waveguide. The peak positions of the intensities are different, and the bases of the distributions partially overlap between the two absorbers.
    Type: Grant
    Filed: December 27, 2000
    Date of Patent: October 15, 2002
    Assignee: Fujitsu Limited
    Inventors: Takehito Tanaka, Yoshinobu Kubota
  • Publication number: 20020141035
    Abstract: An acousto-optic scanning system, which relies on two counter propagating acoustic waves with the same frequency modulation. This scheme completely suppresses the linear frequency chirp, and thus enables the generation of fast non-linear scans and non-constant linear scans. By changing the phase between the modulating signals, this scheme also provides fast longitudinal scans of the focal point.
    Type: Application
    Filed: December 13, 2001
    Publication date: October 3, 2002
    Applicant: YEDA RESEARCH AND DEVELOPMENT CO. LTD.
    Inventors: Nir Davidson, Nir Friedman, Ariel Kaplan
  • Publication number: 20020136524
    Abstract: Unique multi-diffraction structures using electronically controlled Bragg diffraction devices such as acousto-optic (AO) devices to accomplish optical beam attenuation control functions. These variable optical attenuator (VOA) modules can be fully inertialess as they can use electronically programmable sub-microsecond speed AO devices to implement optical gain controls. These VOAs deliver desirable capabilities in one optically reversible unit, making high dynamic range, low loss, high power handling, ultra-fast, high optical isolation, broadband operation, self-aligning robust modules. These VOAs can be made essentially independent of the optical polarization of the incident light by the use of a unique fixed waveplate compensation technique within the VOA configuration that suppresses polarization dependent loss. Broadband gain control operation over several wavelengths can be achieved by controlling the frequency and electrical drive power of the chosen frequencies feeding the acousto-optic devices.
    Type: Application
    Filed: March 14, 2002
    Publication date: September 26, 2002
    Inventor: Nabeel Agha Riza
  • Patent number: 6449083
    Abstract: The invention is intended to present a multi-channel optical modulator small in crosstalk, being used in a laser external modulator of an optical recording apparatus. To achieve the object, the multi-channel optical modulator comprises a plurality of first electrodes (13) provided on one side of an acoustic-optical medium (11), a plurality of piezoelectric elements (12) provided on the first electrodes (13), a plurality of second electrodes (14) provided on the piezoelectric elements (12), a plurality of first lead wires (15) connected individually to the second electrodes (14), and a plurality of second lead wires (16) connected individually to the first electrodes (13), and thereby the crosstalk is small.
    Type: Grant
    Filed: November 30, 2000
    Date of Patent: September 10, 2002
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventor: Toshimi Nishiyama
  • Patent number: 6445487
    Abstract: A system and method for reducing or eliminating the speckle intensity distribution of a laser imaging system. In one embodiment of the invention, a radio frequency signal is injected into a semiconductor laser light source (12) for a projection system (10) to create different speckle patterns that blend together on a projection surface (19). In another embodiment of the invention, optical feedback is used to induce a laser light source for a projection system (10) to create different speckle patterns that blend together on a projection surface (19). In another embodiment of the invention, the laser light source wavelength is Doppler shifted to produce different speckle patterns. In another embodiment of the invention, a means of deflection is used to directionally move the beam to reduce noticeable speckle.
    Type: Grant
    Filed: February 20, 2001
    Date of Patent: September 3, 2002
    Assignee: Eastman Kodak Company
    Inventors: James E. Roddy, William R. Markis
  • Publication number: 20020114057
    Abstract: A system and method for reducing or eliminating the speckle intensity distribution of a laser imaging system. In one embodiment of the invention, a radio frequency signal is injected into a semiconductor laser light source (12) for a projection system (10) to create different speckle patterns that blend together on a projection surface (19). In another embodiment of the invention, optical feedback is used to induce a laser light source for a projection system (10) to create different speckle patterns that blend together on a projection surface (19). In another embodiment of the invention, the laser light source wavelength is Doppler shifted to produce different speckle patterns. In another embodiment of the invention, a means of deflection is used to directionally move the beam to reduce noticeable speckle.
    Type: Application
    Filed: February 20, 2001
    Publication date: August 22, 2002
    Applicant: Eastman Kodak Company
    Inventors: James E. Roddy, William R. Markis
  • Patent number: 6433916
    Abstract: A method for increasing the tunable range of a single acousto-optic tunable filter includes the steps of generating an active steering beam on a piezoelectric transducer and configuring the electrodes of the piezoelectric transducer to reduce the tuning frequency at short wavelengths and increasing the tuning frequency at long wavelengths. The piezoelectric transducer is mounted in relation with an optically transparent crystal at an angle such that the fixed launch angle in combination with the driving frequency provides a greater that one octave spectra to be filtered in a single AOTF.
    Type: Grant
    Filed: June 30, 2000
    Date of Patent: August 13, 2002
    Inventors: Leon Bademian, Allister McNeish
  • Patent number: 6426828
    Abstract: A system of inducing a phase shift using moving reflector elements. The moving reflectors can be moving mirrors or an acousto-optical filter. The moving reflectors oscillate i.e. the move first in a first direction and then in a second direction. Two different reflectors are used so that the light can be switched between the reflectors. During a first portion of the cycle the light is coupled to the first modulator which moves the reflector in the first direction. The second modulator is out of phase with the first modulator, and the light is switched to that second modulator during a second portion of the cycle. The second modulator is also moving in the first direction when the light is applied thereto. In this way, the light obtains a constant direction Doppler shift.
    Type: Grant
    Filed: January 5, 2000
    Date of Patent: July 30, 2002
    Assignee: California Institute of Technology
    Inventor: Roman C. Gutierrez
  • Patent number: 6424451
    Abstract: An acousto-optic tunable filter (AOTF) utilizing phased array transducers for use as dynamically reconfigurable wavelength division multiplexer. The new type of AOTF has the unique capability of simultaneous and independent selection of multi-wavelength signals and separation into multiple output ports. Preferred embodiments of the AOTF are described that provide increased resolution, narrow channel spacing, lower drive power and reduced coherent crosswalk.
    Type: Grant
    Filed: May 22, 1999
    Date of Patent: July 23, 2002
    Inventor: I-Cheng Chang
  • Publication number: 20020093719
    Abstract: An optical reticle substrate inspection apparatus is provided with a laser, a first acoustooptical element which scans a laser beam output form the laser, and a second acoustooptical element which generates a virtual image with a concave lens effect to the laser beam output from the first acoustooptical element. The optical reticle substrate inspection apparatus is further provided with a concave lens arranged on the output side of the laser beam of the second acoustooptical element and an optical system which images the virtual image on a reticle substrate being an object to be inspected. The concave lens magnifies the laser beam in a perpendicular direction to the scanning direction by the first acoustooptical element.
    Type: Application
    Filed: November 29, 2001
    Publication date: July 18, 2002
    Applicant: NEC Corporation
    Inventor: Motonari Tateno
  • Patent number: 6421164
    Abstract: An apparatus for performing high speed scanning of an optical delay and its application for performing optical interferometry, ranging, and imaging, including cross sectional imaging using optical coherence tomography, is disclosed. The apparatus achieves optical delay scanning by using diffractive optical elements in conjunction with imaging optics. In one embodiment a diffraction grating disperses an optical beam into different spectral frequency or wavelength components which are collimated by a lens. A mirror is placed one focal length away from the lens and the alteration of the grating groove density, the grating input angle, the grating output angle, and/or the mirror tilt produce a change in optical group and phase delay. This apparatus permits the optical group and phase delay to be scanned by scanning the angle of the mirror. In other embodiments, this device permits optical delay scanning without the use of moving parts.
    Type: Grant
    Filed: June 13, 2001
    Date of Patent: July 16, 2002
    Assignee: Massachusetts Institute of Technology
    Inventors: Guillermo Tearney, Brett E. Bouma, James G. Fujimoto
  • Patent number: 6417953
    Abstract: Disclosed is a laser optical system including a multiline laser source that emits a laser beam having a plurality of peak wavelengths, a wavelength separating optical system that separates the laser beam emitted from the laser source into two monochromatic beams, a pair of modulating optical systems that modulate intensities of the monochromatic beams, a beam combining optical system that combines the laser beams modulated by the modulating optical systems, a deflector for deflecting a plurality of laser beam combined by the beam combining optical system, and a converging optical system that converges the laser beams deflected by the deflector to form beam spots on an object surface to be exposed. The modulating optical systems, which include diffractive beam-dividing elements, are optimized for the respective monochromatic beams to form the beam spots at the identical pitches on the object surface.
    Type: Grant
    Filed: July 7, 2000
    Date of Patent: July 9, 2002
    Assignee: Asahi Kogaku Kogyo Kabushiki Kaisha
    Inventor: Takashi Iizuka
  • Patent number: 6407848
    Abstract: Multi-domain, phase-compensated, differential-coherence detection of photonic signals for interferometric processes and devices may be manufactured holographically and developed in situ or with an automatic registration between holograms and photonic sources in a single frame. Photonic or electronic post processing may include outputs from a cycling or rotation between differently phased complementary outputs of constructive and destructive interference. A hyper-selective, direct-conversion, expanded-bandpass filter may rely on an expanded bandpass for ease of filtering, with no dead zones for zero beat frequency cases. A hyper-heterodyning, expanded bandpass system may also provide improved filtering and signal-to-noise ratios. An ultra-high-resolution, broadband spectrum analyzer may operate in multiple domains, including complex “fingerprints” of phase, frequency, and other parameters.
    Type: Grant
    Filed: December 27, 2000
    Date of Patent: June 18, 2002
    Assignee: All Optical Networks, Inc.
    Inventors: Arkady S. Bablumyan, Dmitry Berger, John N. Hait, Bruce E. Smith
  • Patent number: 6404536
    Abstract: The present invention pertains to a polarization independent tunable acousto-optical filter and the corresponding method. The filter diffracts an input light beam into a first input light beam unaffected by acoustic waves and a second input light beam affected by acoustic waves. A polarization beam displacer/combiner is employed to separate the input light beam into two orthogonal beams. Several polarized rotators are used to rotate the polarization of light by 90 degrees. An acousto-optical device makes the polarization of light with a particular wavelength rotate by 90 degrees. The two beams are then properly combined to form orthogonal beams. The filtering method has nothing to do with the polarization of the incident light. The filter has such advantages as a high extinction ratio, a small volume and a lower cost.
    Type: Grant
    Filed: March 8, 2001
    Date of Patent: June 11, 2002
    Assignee: Industrial Technology Research Institute
    Inventors: Eric Gung-Hwa Lean, Chen-Bin Huang, Wei-Jen Chou, Shu-Mei Yang, Chieh Hu
  • Publication number: 20020063942
    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: Application
    Filed: October 30, 2001
    Publication date: May 30, 2002
    Applicant: Heidelberger Druckmaschinen AG
    Inventors: Joerg-Achim Fischer, Axel Gebhardt, Peter Ressel
  • Publication number: 20020048075
    Abstract: The invention relates to an optical modulation device for coupling an entering radiation field (12), with which an incident radiation field (40) is divided into a transmitted branch (40T) and a diffracted branch (40B) by means of a first acousto-optical modulation and a diffracted and a transmitted branch are respectively generated by means of a second acousto-optical modulation so that the transmitted branch (40BUT) resulting from the deflected diffracted branch (40BU) and the diffracted branch (40TUB) resulting from the deflected transmitted branch (40TU) propagate in approximately the same direction and form a first radiation field (46) as a result of essentially constructive interference and, in addition, the transmitted branch (40TUT) resulting from the deflected transmitted branch (40TU) and the diffracted branch (40BUB) resulting from the deflected diffracted branch (40BU) propagate in the same direction and form a second radiation field (48) as a result of essentially destructive interference.
    Type: Application
    Filed: August 31, 2001
    Publication date: April 25, 2002
    Applicant: HAAS-LASER GmbH & Co. KG
    Inventor: Malte Kumkar
  • Publication number: 20020044332
    Abstract: An optical arrangement having a light source, preferably a laser, for generating a light beam (1); at least one acoustooptical deflection device (3) for the light beam (1); and a correction device for correcting beam aberrations produced by the deflection device (3) is configured, in the interest of flexible and reliable correction of aberrations occurring because of the deflection, in such a way that the correction device comprises an adaptive optical system (2). Also described is a method for the deflection of light beams (1) with a light source, preferably a laser, for generating a light beam (1); at least one acoustooptical deflection device (3) for the light beam (1); and a correction device for correcting beam aberrations produced by the deflection device (3), in which an adaptive optical system (2) is used as the correction device.
    Type: Application
    Filed: October 3, 2001
    Publication date: April 18, 2002
    Inventors: Johann Engelhardt, Juergen Hoffmann
  • Publication number: 20010040718
    Abstract: A telemetry system includes a plurality of acoustic sensors for receiving acoustic information and generating analog signals based on the received acoustic information. A first plurality of subsystems is coupled to at least a subset of the plurality of acoustic sensors. The first plurality of subsystems is configured to receive the analog signals from the acoustic sensors and generate digital values based on the received analog signals. The system includes a first optical splitter. A first optical transmitter transmits a first set of optical pulses to the first optical splitter. The first optical splitter is configured to transmit the first set of optical pulses to each subsystem in the first plurality of subsystems. Each subsystem in the first plurality of subsystems is configured to modulate the first set of optical pulses based on the generated digital values and thereby generate a modulated optical pulse stream.
    Type: Application
    Filed: May 2, 2001
    Publication date: November 15, 2001
    Applicant: Lockheed Martin Corporation
    Inventor: VanWinkle (Van) T. Townsend
  • Patent number: 6317170
    Abstract: A video image projection apparatus is disclosed. The apparatus uses a laser as a light source and modulates the light beam using a modulator according to an image signal. The apparatus projects the modulated light to a screen using a light scanning system. The laser display system includes three primary color laser light sources, an optical system needed for three-color light combining/separation, a light modulator loading the image signal into the three-color laser, and a driving circuit driving the system by processing the video signal electronically. A hybrid video laser color mixer has a structure that combines very small-sized hybrid light beam combining/separation optical elements and a 3-channel light modulator. It allows the size of the image projection apparatus to be about 6 by 5 by 3 centimeters. Additionally, the light alignment of the elements is close to self-alignment.
    Type: Grant
    Filed: June 30, 1998
    Date of Patent: November 13, 2001
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Young Mo Hwang, Seung Nam Cha, Jin Ho Lee
  • Patent number: 6307665
    Abstract: An acousto-optic modulator including an ultrasonic medium for controlling light from an optical source through diffraction, two transducers each having one electrode formed on one side thereof, the electrodes being for generating an acousto-elastic wave, and a conductive adhesive layer interposed between the ultrasonic medium and each of the sides of the transducers opposite to the sides on which the electrodes are installed, in order to adhere each of the transducers to the ultrasonic medium.
    Type: Grant
    Filed: March 22, 1999
    Date of Patent: October 23, 2001
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Yong-hoon Kim, Hang-woo Lee
  • Publication number: 20010030795
    Abstract: The invention offers a hard carbon film and a SAW substrate that are easy to fabricate or low in manufacturing cost while virtually maintaining the quality that affects the important properties of a device that comprises the hard carbon film or the SAW substrate. The hard carbon film comprises a composite film of graphite-like diamond and carbon clusters; the composite film has a continuous crystal structure.
    Type: Application
    Filed: December 19, 2000
    Publication date: October 18, 2001
    Applicant: Sumitomo Electric Industries, Ltd.
    Inventors: Satoshi Fujii, Tomoki Uemura, Yuichiro Seki, Hideaki Nakahata, Shinichi Shikata
  • Patent number: 6295157
    Abstract: An acousto-optic modulator for use with a multi-channel laser beam system, for instance, is of conventional structure except that two different RF (radio frequency) signals drive the modulator. These signals each produce at least one output beam as diffracted by the modulator body. These two beams are angularly and spatially separated. One of the sets of beams is incident upon a beam stop, and therefore is not used for writing. Only the other set of beams, driven by the other of the frequencies, performs the actual writing. The optical stop in addition to blocking one of the sets of diffracted beams also blocks the transmission of the zero order (undiffracted) beam. The sum of the load power of the signals at the two frequencies is kept approximately constant, thereby maintaining a constant thermal condition within the modulator.
    Type: Grant
    Filed: August 23, 1999
    Date of Patent: September 25, 2001
    Assignee: Etec Systems, Inc.
    Inventors: Paul C. Allen, Jerry Martyniuk
  • Patent number: 6282011
    Abstract: An apparatus for performing high speed scanning of an optical delay and its application for performing optical interferometry, ranging, and imaging, including cross sectional imaging using optical coherence tomography, is disclosed. The apparatus achieves optical delay scanning by using diffractive optical elements in conjunction with imaging optics. In one embodiment a diffraction grating disperses an optical beam into different spectral frequency or wavelength components which are collimated by a lens. A mirror is placed one focal length away from the lens and the alteration of the grating groove density, the grating input angle, the grating output angle, and/or the mirror tilt produce a change in optical group and phase delay. This apparatus permits the optical group and phase delay to be scanned by scanning the angle of the mirror. In other embodiments, this device permits optical delay scanning without the use of moving parts.
    Type: Grant
    Filed: June 26, 2000
    Date of Patent: August 28, 2001
    Assignee: Massachusetts Institute of Technology
    Inventors: Guillermo Tearney, Brett E. Bouma, James G. Fujimoto
  • Patent number: 6281948
    Abstract: In a device for the deflection of a light bundle generated by a light source, wherein this device has a nonmechanical deflection device in which the light bundle enters and exits at a different angle determined by a controlling variable, which angle depends on the wavelength of every light component in the light bundle, it is provided that an optically dispersively active system is provided behind the nonmechanical deflection device in the light propagation direction, wherein the angular dispersion of this system is dependent on the angle of the light bundle entering the system, wherein the angular dispersion compensates for the wavelength dependence of the angle of the nonmechanical deflection device determined by the controlling variable.
    Type: Grant
    Filed: January 28, 1999
    Date of Patent: August 28, 2001
    Assignee: LDT GmbH & Co. Laser-Display-Technologies KG
    Inventor: Christhard Deter
  • Patent number: 6243216
    Abstract: A fast responding optical modulating device for a high-density recording using in an optical pickup includes a light source, an optical modulator and a pair of lenses. The pair of lenses are so arranged that the distance between the lenses is shorter than the sum of each focal length of the lenses. The device can adjust an optical spot size at the center of the optical modulator by changing the position of the lenses without altering the whole length between the light source and optical modulator. Therefore, the device can increase the rise time as desired and the optical efficiency in optical modulation for high-density recording which uses a short wavelength light source, and moreover, has an effect of simplifying the high-density recording.
    Type: Grant
    Filed: July 27, 1995
    Date of Patent: June 5, 2001
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Jang-hoon Yoo, Pyong-yong Seong
  • Patent number: 6226427
    Abstract: Disclosed is an optical isolator, which has: a medium through which a light transmits and in which a dynamic diffraction grating that periodically repeats a refractive index distribution is formed; wherein the dynamic diffraction grating causes a propagation loss difference between an incident light which is supplied into the medium and a returning light which is supplied into the medium in a direction reverse to the incident light.
    Type: Grant
    Filed: April 30, 1999
    Date of Patent: May 1, 2001
    Assignee: NEC Corporation
    Inventor: Yidong Nuang
  • Patent number: 6188507
    Abstract: A variable acousto-optic spectrum projector is disclosed. The invention may include a radiation source, an entrance slit, a lens or mirror, a Bragg cell, an arbitrary function generator for driving a transducer of the Bragg cell, another lens or mirror, an exit slit, and a collimating lens. In a first embodiment of the invention, the Bragg cell comprises a Tl3AsSe3 crystal and emits light in the 7 to 11 &mgr;m range (long-wave infrared) with a spectral resolution of between 4.5 and 7 cm−1. In a second embodiment of the invention, the Bragg cell comprises a TeO2 crystal and emits light in the 420 to 720 nm range (visible) with a spectral resolution of between 50 and 80 cm−1.
    Type: Grant
    Filed: March 17, 1999
    Date of Patent: February 13, 2001
    Assignee: Mission Research Corporation
    Inventor: Matthew C. Thomas
  • Patent number: 6129884
    Abstract: A rapid prototyping and manufacturing (e.g. stereolithography) method and apparatus for producing three-dimensional objects by selectively subjecting a liquid or other fluid-like material to a beam of prescribed stimulation. In a preferred embodiment a source of prescribed stimulation is controlled to reduce or inhibit the production of the prescribed stimulation during at least some periods when the prescribed stimulation is not needed to expose the material. In another preferred embodiment, the source of stimulation is controlled to vary the quantity of prescribed stimulation that is produced and allowed to reach the material. In an additional preferred embodiment, control of laser output occurs based on a combination of supplying a regulated amount of voltage to an AOM in conjunction with temporary sensing of laser power and a known desired power to attain.
    Type: Grant
    Filed: February 8, 1999
    Date of Patent: October 10, 2000
    Assignee: 3D Systems, Inc.
    Inventors: Ross D. Beers, Arvind Chari, Jouni P. Partanen, Nansheng Tang
  • Patent number: 6115171
    Abstract: An electrochromic device comprising a pair of electrically conductive substrates disposed facing each other and each having at least on its inner surface an electrode at least one of said electrically conductive substrates comprising a transparent substrate and a transparent electrode, an ion conductive material inserted between said pair of electrically conductive substrates, an electrochromic material-containing layer disposed between either one of said electrodes and said ion conductive material and an ultraviolet absorptive layer disposed between either at least one of said transparent substrates and the electrode disposed thereover or on the surface of said transparent substrate opposite to the transparent electrode disposed thereover, said ultraviolet absorptive layer being formed by coating and curing on the surface at said transparent substrate a reaction product of (A) an aminosilane compound of the formula (I) or the derivative thereof and (B) an ultraviolet absorptive material having in its molecul
    Type: Grant
    Filed: June 1, 1999
    Date of Patent: September 5, 2000
    Assignee: Nippon Mitsubishi Oil Corporation
    Inventors: Masaki Minami, Tsuyoshi Asano, Noboru Takaesu, Yoshinori Nishikitani
  • Patent number: 6088150
    Abstract: A 3-channel modulation system for a high power laser and a modulation method for a high power laser are disclosed herein. In a preferred implementation, the modulation system includes a laser light source, a light modulator modulating the light generated from the laser light source and including a pair of electrodes having a predetermined area disposed on one side of the light modulator, an image signal generating sub-system, a drive circuit sub-system for operating the electrodes so that the image signal being generated from the image signal generating sub-system is provided through the electrodes to the light modulator, a first cylindrical lens positioned between the laser light source and the light modulator so that the area and form of the light generated from the laser light source are modified and the modified light enters the light modulator, and a second cylindrical lens positioned at an output side of the light modulator to modify the area and form of the light modulated by the light modulator.
    Type: Grant
    Filed: April 15, 1998
    Date of Patent: July 11, 2000
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Yong Hoon Kim, Seung Nam Cha, Hang Woo Lee