Electro-optic Patents (Class 372/12)
  • Patent number: 4507785
    Abstract: An unpolarized electro-optically Q-switched laser using a laser rod (4), a prism (1) and a Pockels cell (5) between a pair of mirrors (2, 3) wherein the prism (1) is selected to give a low-angle walk-off arranged that when a quarter wave length voltage is applied to the Pockels cell the first pass will be cancelled by an equal and opposite walk-off during the return path.
    Type: Grant
    Filed: November 26, 1982
    Date of Patent: March 26, 1985
    Assignee: The Commonwealth of Australia
    Inventor: James Richards
  • Patent number: 4485473
    Abstract: An amplitude modulator for a tunable ring cavity dye laser is disclosed. The modulator is operated in time synchronization with the laser pump and is located assymetrically within the ring to attenuate dye laser pulses in one direction while passing pulses in the opposite direction, thereby producing a mode locked unidirectional travelling wave. The use of a low dispersion electro-optical modulator in a dye laser yields subpicosecond optical pulses with wide tunability.
    Type: Grant
    Filed: April 29, 1982
    Date of Patent: November 27, 1984
    Assignee: Cornell Research Foundation, Inc.
    Inventors: Chung L. Tang, Nils A. Olsson, Jean-Marc Halbout
  • Patent number: 4484333
    Abstract: An RF discharge waveguide laser is modulated by an electro-optic modulator positioned in a second optical cavity coupled to a gain cavity containing the waveguide.
    Type: Grant
    Filed: February 12, 1982
    Date of Patent: November 20, 1984
    Assignee: United Technologies Corporation
    Inventors: Peter P. Chenausky, Richard A. Hart, Lanny M. Laughman, Ronald E. Belek, Robert J. Wayne
  • Patent number: 4483005
    Abstract: Reducing the widths of pulses in a beam from a laser by passing the beam through means to rotate the plane of polarization of the beam when a voltage is applied and reflecting the beam back through the means to rotate to a polarizer, the voltage being applied for a length of time equal to the desired pulse width, the portions of the pulses that have passed through the means to rotate when the voltage was applied being deflected by the polarizer into an output beam, the portions of the pulses that have passed through the means to rotate when the voltage was not applied being passed directly through the polarizer without being deflected into the output beam.
    Type: Grant
    Filed: September 24, 1981
    Date of Patent: November 13, 1984
    Assignee: Teradyne, Inc.
    Inventor: Donald V. Smart
  • Patent number: 4468776
    Abstract: A uv preionized CO.sub.2 oscillator with integral four-pass amplifier capable of providing 1 to 5 GW laser pulses with pulse widths from 0.1 to 0.5 ns full width at half-maximum (FWHM) is described. The apparatus is operated at any pressure from 1 atm to 10 atm without the necessity of complex high voltage electronics. The reinjection technique employed gives rise to a compact, efficient system that is particularly immune to alignment instabilities with a minimal amount of hardware and complexity.
    Type: Grant
    Filed: August 20, 1981
    Date of Patent: August 28, 1984
    Assignee: The United States of America as represented by the United States Department of Energy
    Inventor: Edward J. McLellan
  • Patent number: 4461005
    Abstract: A laser system and method is disclosed which is capable of producing high peak power, high pulse rates, and narrow pulses. The invention comprises an acousto-optic shutter and a frustrated total internal reflectance Q-switch in a unique configuration which allows maximum power to be obtained from the laser device while still achieving high pulse rate and narrow pulse width.
    Type: Grant
    Filed: October 27, 1980
    Date of Patent: July 17, 1984
    Inventors: Ernest M. Ward, Eugene L. Curry, Richard J. Newton
  • Patent number: 4441186
    Abstract: An electronically switchable multiwavelength laser system comprises a lasing medium capable of generating a beam having at least two different wavelengths, an anisotropic birefringent component in optical alignment with the medium for refracting the beam into spatially separate polarized rays containing both wavelengths, and another electrically controllable anisotropic electrooptically active element, such as a Pockels' cell, having electrodes aligned with the respective rays and selectively energizable to block either ray to permit the laser to oscillate at the wavelength and polarization of the unblocked ray. The laser system includes highly reflective and partially transmissive mirrors defining the laser cavity and assisting in wavelength discrimination, the birefringent component and Pockels' cell being disposed in series between the lasing medium and the highly reflective mirror.
    Type: Grant
    Filed: December 31, 1981
    Date of Patent: April 3, 1984
    Assignee: GTE Products Corporation
    Inventor: Edward G. Erickson
  • Patent number: 4403833
    Abstract: Apparatus (FIG. 2) receives light (11) in an input direction (12) and controls the directions in which portions of it travel through regions (13,14) to emerge (at 15) in an output direction (16) with intensity responsive to the product of two electrical potential differences multiplied together.Electrooptic reflective means (18) comprising two electrodes (19,20), on a region (13) in a waveguide (17), form a first Bragg grating (18) with a direction of Bragg incidence in the input direction (12). Similar means (23) comprising two electrodes (24,25), on a region (14), form a second Bragg grating (23) with a direction of Bragg incidence the same as a direction of Bragg reflection (22) from the first grating.A prism (26) directs light (11) from a laser (27) to enter in the input direction (12) into the electrooptic means (18).
    Type: Grant
    Filed: August 18, 1981
    Date of Patent: September 13, 1983
    Assignee: Battelle Memorial Institute
    Inventors: Richard P. Kenan, Carl M. Verber
  • Patent number: 4399541
    Abstract: A known electro-optic has a semiconductor laser, a temperature sensor for controlling an electrically operated cooler, and an optical fiber end portion anchored close to the laser to receive light from it. Usually the fiber is anchored by a mass of cured epoxy. This invention proposes anchoring the fiber in a mass of fusible alloy which is melted and solidified using a Peltier effect device which is driven with one polarity current to function as a heater and with a reverse polarity current to function as a cooler. Once the package is complete and the laser is operating, the temperature sensor together with the Peltier effect device functioning as a cooler are used to cool the laser.
    Type: Grant
    Filed: February 17, 1981
    Date of Patent: August 16, 1983
    Assignee: Northern Telecom Limited
    Inventors: Tibor F. I. Kovats, Tibor F. Devenyi, Christopher M. Look
  • Patent number: 4380073
    Abstract: An electro-optically Q-switched cavity-dumped laser is improved by the addition of an injection control laser, so that time jitter is reduced, frequency stability is improved, higher peak circulating power in the Q-switch pulse is achieved, an intracavity grating is no longer required.
    Type: Grant
    Filed: November 10, 1980
    Date of Patent: April 12, 1983
    Assignee: United Technologies Corporation
    Inventor: Robert J. Wayne
  • Patent number: 4375684
    Abstract: A single element interposed in a laser resonator cavity provides for AM mode-locking, Q-switching and dumping in a sequential operation in which a Pockels cell or like polarization rotation device is first energized to prevent build-up of radiation in a laser cavity, is then switched to provide for mode-locking by energization with a periodically varying signal, and is finally energized to dump a single mode-locked pulse. The sequential operation permits the use of a single electro-optic element and a single pair of electrodes. Q-switching, mode-locking and dumping are accomplished utilizing the same physical effect in the crystal, e.g., polarization rotation.
    Type: Grant
    Filed: July 28, 1980
    Date of Patent: March 1, 1983
    Assignee: Jersey Nuclear-Avco Isotopes, Inc.
    Inventor: Patrick N. Everett
  • Patent number: 4331387
    Abstract: Electro-optical apparatus for modulating a randomly polarized light beam is disclosed. The apparatus includes an electro-optical cell and a plurality of optical elements configured to polarize the randomly polarized light beam into two light beam components and to guide the light beam components along two respectively corresponding sets of optical paths, a portion of each set of optical paths passing colinearly through a predetermined axis of the electro-optical cell. Each set of paths are combined to reform an associated portion of the randomly polarized light beam which is exited at a corresponding exit surface of the apparatus, the reformed exited portion, in each case, being a function of the energization of the electro-optical cell. In one application, the electro-optical apparatus is disposed in the optical cavity of a laser system and operative therein as a Q modulator wherein the Q of the laser cavity is dependent on the energization level of the electro-optical cell.
    Type: Grant
    Filed: July 3, 1980
    Date of Patent: May 25, 1982
    Assignee: Westinghouse Electric Corp.
    Inventor: John L. Wentz
  • Patent number: 4313651
    Abstract: The optical beam scanner employs novel utilization of the well known Stark effect. By means of an external applied voltage, a change in the index of refraction of an optical medium is produced. This produces a bending effect on light transmitted through the medium. Varying the applied voltage can be used to vary the refractive index, or a refractive index gradient may be produced by providing a gradient in the applied field, to produce no moving parts scanning of the optical beam.
    Type: Grant
    Filed: February 22, 1979
    Date of Patent: February 2, 1982
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventor: Walter E. Miller, Jr.