Pockels Cell Patents (Class 359/257)
  • Patent number: 5585735
    Abstract: An E-O probe for a two-dimentional voltage detecting apparatus using a fiber optic plate is provided. The fiber optic plate has a bottom face facing a measured object and a bundle of a plurality of cores separated from one another by cladding electro-optic material is attached to an end of each core at said bottom face side. A reflecting surface is provided on the bottom face side of the fiber optic plate for reflecting light back toward the side of the fiber optic plate opposite said bottom face. The refractive index of said electro-optic material varies in response to the intensity of an electric field applied to the electro-optic material. A two-dimentional voltage detecting apparatus using the E-O probe is further provided which has a high spatial resolution.
    Type: Grant
    Filed: January 6, 1995
    Date of Patent: December 17, 1996
    Assignee: Hamamatsu Photonics K.K.
    Inventors: Hironori Takahashi, Teruo Hiruma
  • Patent number: 5548234
    Abstract: A two-step solid state optical switch system includes an electro-optical material positioned between a first electrode and a grounded second electrode. A voltage source is electrically connectable to the first electrode by an ON switch. When the ON switch is closed, a plurality of field effect transistors establish electrical contact between the voltage source and the first electrode to charge the first electrode and change the optical characteristics of the electro-optical material. An OFF switch, which is also electrically connectable to the first electrode, includes a plurality of field effect transistors, which establish electrical contact between ground and the first electrode when the OFF switch is closed. With the closing of the OFF switch, any voltage on the first electrode is removed to restore the optical characteristics of the electro-optical material.
    Type: Grant
    Filed: December 21, 1994
    Date of Patent: August 20, 1996
    Assignee: Intelligent Surgical Lasers, Inc.
    Inventors: Laszlo Turi, Richard Ujazdowski, Tibor Juhasz
  • Patent number: 5528414
    Abstract: A two-dimensional modulator array for modulating a plurality of light beams. The modulator array is comprised of a plurality of stacked wafer layers. Each of the wafer layers have a linear array of transversely driven Pockels modulators. The Pockels modulators are formed by placing a plurality of electrodes over a top surface of an optical material and extending the electrodes over a beveled edge of the optical material. A ground plane resides on the bottom surface of the optical material. Conductive end reflectors are associated with each of the modulator electrodes. These end reflectors reflect the light beams back through the wafer. Electrical attachments are connected to the ends of each electrode for controlling the modulation for each electrode. Thereby, separate light beams can be individually modulated.
    Type: Grant
    Filed: May 5, 1994
    Date of Patent: June 18, 1996
    Assignee: LOTS Technology
    Inventor: William S. Oakley
  • Patent number: 5448396
    Abstract: A photo isolator transmits light of a frequency fo in the normal direction and substantially intercepts the light in the reverse direction. A phase modulator comprising an optical crystal having a refractive index, counter faces and counter electrodes formed on the counter faces. The phase modulator receives an electrical signal having a frequency of .DELTA.f or higher and changes the refractive index of the optical crystal by the Pockels effect. A narrow band pass filter has a half band width of .DELTA.f, is mounted on an optical axis, and substantially transmits light having frequency of from (fo-.DELTA.f) to (fo+.DELTA.f). The phase modulator is juxtaposed with the narrow band pass filter on the optical axis.
    Type: Grant
    Filed: August 31, 1993
    Date of Patent: September 5, 1995
    Assignee: Fujitsu Limited
    Inventor: Takehiro Fukushima
  • Patent number: 5410425
    Abstract: Magnetron cathodes, which produce high current discharges, form greatly improved plasma electrodes on each side of an electro-optic crystal. The plasma electrode has a low pressure gas region on both sides of the crystal. When the gas is ionized, e.g., by a glow discharge in the low pressure gas, the plasma formed is a good conductor. The gas electrode acts as a highly uniform conducting electrode. Since the plasma is transparent to a high energy laser beam passing through the crystal, the plasma is transparent. A crystal exposed from two sides to such a plasma can be charged up uniformly to any desired voltage. A typical configuration utilizes helium at 50 millitorr operating. pressure and 2 kA discharge current. The magnetron cathode produces a more uniform plasma and allows a reduced operating pressure which leads to lower plasma resistivity and a more uniform charge on the crystal.
    Type: Grant
    Filed: May 10, 1993
    Date of Patent: April 25, 1995
    Assignee: The United States of America as represented by the United States Department of Energy
    Inventor: Mark A. Rhodes
  • Patent number: 5303020
    Abstract: An optical transceiver is provided for transmitting a light pulse to a target and for receiving a reflected light pulse from the target. The transceiver includes a light source for transmitting a coherent light pulse which is reflected by the target along a first optical path as a reflected light pulse. The transceiver also includes a trigger signal generating circuit, coupled to the light source, for generating a trigger signal to indicate when the light pulse is transmitted. The transceiver further employs an attenuation device, responsive to the trigger signal and situated in the first optical path to intercept the reflected light pulse, for attenuating optical transmission through the first optical path inversely as a function of time from generation of the light pulse. In this manner, reflected light pulses reflected from targets close to the transceiver receive a greater amount of attenuation than reflected light pulses reflected from more distant targets.
    Type: Grant
    Filed: December 30, 1992
    Date of Patent: April 12, 1994
    Assignee: Litton Systems, Inc.
    Inventor: Michael G. Croteau
  • Patent number: 5221988
    Abstract: A device for damping the vibrations of an elongated, substantially rectangular crystal in response to an applied high voltage electrical field comprises a pair of dielectric panes which are impedance matched with the crystal and are attached to opposite sides thereof. As attached to the crystal, each of the panes is disposed at the periphery of the electrical field, and an aluminum block is attached to each of the panes on a surface which is opposite from the crystal. The mass of aluminum blocks, and the texture of their exposed outer surfaces cooperate to mechanically dampen the acoustic vibrations transmitted from the crystal through the panes. Additionally, the rectangular dimensions of the crystal are chosen to delay the propagation of acoustic waves from the surfaces of the crystal to its center.
    Type: Grant
    Filed: November 21, 1991
    Date of Patent: June 22, 1993
    Assignee: Intelligent Surgical Lasers
    Inventor: Tibor Juhasz
  • Patent number: 5220451
    Abstract: The present invention relates to a high performance nonlinear optical device by utilizing an optical medium of large second order nonlinear optical effects, which has acceptable processability and stability. The second-order nonlinear optical device of the present invention comprises an optical element of a monoclinic crystal of 4-hydroxy-3-methoxy-4'-nitrostilbene represented by the formula (I): ##STR1## said crystal belonging to space group P2.sub.1, point group #4, said optical element having at least one substantially optically smooth surface.
    Type: Grant
    Filed: February 27, 1991
    Date of Patent: June 15, 1993
    Assignee: Toray Industries, Inc.
    Inventors: Tetsuya Gotoh, Tetsuya Tsunekawa, Seiji Fukuda, Hiroshi Mataki, Keiichi Egawa
  • Patent number: 5130528
    Abstract: A heterojunction optical switch is taught. Briefly stated, birefringence in the form of a Pockel Cell is utilized such that biasing of the Pockel Cell permits the passage of light therethrough. Preferably, a light detector and resistor are electrically in parallel with the Pockel Cell such that light impinging upon the light detector causes the Pockel Cell to be reverse biased with the result that a separate light source may pass through the Pockel Cell. In this fashion, the Pockel Cell operates as a true optical switch.
    Type: Grant
    Filed: March 1, 1991
    Date of Patent: July 14, 1992
    Assignee: International Business Machines Corporation
    Inventor: Alfred Phillips, Jr.
  • Patent number: 5075795
    Abstract: An electro-optic device, which processes by modulating, switching or gating, a light beam in response to an electrical signal utilizes an electro-optic crystal through which the beam to be processed passes. An electric field is generated by pulses which modulate the crystal's index of refraction and also causes piezoelectric ringing in the crystal. Acoustic energy absorbing material is coupled to the crystal for absorbing the piezoelectrically generated acoustic waves propagating perpendicularly to the applied electric field direction which has been found to be the dominant acoustic mode affecting the birefringence of the crystal and causing the ringing. The field is applied in short pulses (of the order of 10 nsec or less) thereby reducing lower frequencies in the acoustic energy spectrum thereby facilitating the absorption of the ringing energy.
    Type: Grant
    Filed: April 19, 1990
    Date of Patent: December 24, 1991
    Assignee: The University of Rochester
    Inventors: R. J. Dwayne Miller, Pierre Basseras