Patents Represented by Attorney Hay Kyung Chang
  • Patent number: 5452126
    Abstract: A lightweight telescopic lens of monolithic construction is revealed that corporates additional refractive and reflective curved surfaces to produce all the optical functions performed by an ordinary telescope. A pair of such lenses may be mounted in an eyeglass frame to yield a telescope that can be worn like a pair of eyeglasses, thus affording superior image stability as well as free the user's hands. Minor modifications involving the use of several menisci of a different index of refraction from that of the core lens can be made to achieve achromatism of emergent light from achromatic input light. The entire core lens can also be shaped into a meniscus to take advantage of the principle of total internal reflection, thereby increasing the light-gathering aperture while at the same time rendering the lens even more compact and lightweight.
    Type: Grant
    Filed: November 10, 1993
    Date of Patent: September 19, 1995
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventor: John L. Johnson
  • Patent number: 5450041
    Abstract: A high-power oscillator which uses a quasi-optical ring resonator to prov the feedback required for oscillation allows energy to travel in one direction only within the resonator and suffers little loss of energy during operation. The oscillator is built by inserting an array of amplifiers, tuned to a desired frequency, into the quasi-optical ring resonator formed by three reflective mirrors. The mirrors are spaced such that the total loop phase shift is equal to an integer multiple of 360 degrees at the desired frequency and, by proper selection of the amplifiers, the loop gain is set to be greater than or equal to one.
    Type: Grant
    Filed: September 19, 1994
    Date of Patent: September 12, 1995
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Ralph H. Halladay, George A. Emmons
  • Patent number: 5448052
    Abstract: The first identification device located on first vehicle embeds a pre-detined pattern in an outgoing radiation and detects radiation incoming from a second identification device located on second vehicle. The two identification devices are identical to each other in their function. The first device phase-conjugates the incoming radiation and the result is combined with the pattern-containing radiation. The combination is then emitted toward the second device along the exact same optical path as the one taken by the incoming radiation in accordance with the principle of phase conjugation. The second device isolates the pattern from the combination radiation and, if the pattern is recognized, identifies the first vehicle as friendly. The the second device may engage in the same sequence of beamings as performed by the first device to identify itself (the second object to the first object.
    Type: Grant
    Filed: August 12, 1993
    Date of Patent: September 5, 1995
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Travis S. Taylor, Debbee B. Jordan
  • Patent number: 5389791
    Abstract: A conventional rate-stabilized IR seeker is fitted with an improvement that esults in a wider FOV as well as much-reduced image smear. The improvement comprises a circular optical wedge rotatably mounted in front of the optics assembly of the seeker sensor. The combination of the primary scan vector generated by the circulating sensor of the seeker and the secondary scan vector generated by the rotating wedge produces a scan pattern that has a wider total FOV than that of the sensor alone while at the same time providing occasional points of zero or near-zero spatial scan velocity. Such points allow collection of "snapshot" data with little or no image smear.
    Type: Grant
    Filed: January 31, 1994
    Date of Patent: February 14, 1995
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventor: Ronald C. Passmore
  • Patent number: 5374009
    Abstract: The present invention is an initial guidance system for a missile that has o other guidance or inadequate terminal homing guidance to lock onto a target at the time of missile launch. A laser beam projected from the missile launch station is aimed toward the target. Light from the beam is reflected in random directions (scattered) from aerosol particles that are ever present in the atmosphere. This scattered light strikes light detectors that are located on the sides of the missile. When the missile flies off the direction of the target, the amplitudes of impacting light on these detectors are different on different sides of the missile. Guidance controls activated by these amplitude differences cause the missile to veer toward the center of the beam and thus fly in a direction that is more toward the target.
    Type: Grant
    Filed: September 20, 1993
    Date of Patent: December 20, 1994
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Walter E. Miller, Jr., Robert R. Mitchell, Gene H. Widenhofer
  • Patent number: 5328512
    Abstract: A sprayer of an elongated shape receives a desired liquid from an outside urce and spray-applies the liquid onto a fiber in response to motivating force provided by pressurized gas. The unsprayed, virgin fiber enters the sprayer through an inlet hole, is sprayed on with the liquid as it travels the width of the sprayer and exits the sprayer as a sprayed fiber through an exit hole. The pressure of the motivating gas can be varied to provide the optimum jettisoning force for a selected liquid, taking into consideration the viscosity, volatility and other pertinent characteristics of the liquid.
    Type: Grant
    Filed: July 27, 1992
    Date of Patent: July 12, 1994
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Michael L. Steelman, William J. Taylor
  • Patent number: 5268785
    Abstract: Described here is an all-optical switch having two states, one that absorbs ncident coherent optical radiation and another that amplifies incident coherent optical radiation. The state of switch is changed in response to the passage of an ultra-short coherent optical pulse when the peak field strength of the pulse is in a wide region about the effective dipole moment per unit volume, a characteristic material parameter proportional to the density and the dipole transition moment of the selected active two-level systems which are uniformly distributed with sufficient density so that there is more than one two-level system per cubic transition wavelength causing dipole-dipole interactions to be non-negligible.
    Type: Grant
    Filed: February 8, 1993
    Date of Patent: December 7, 1993
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Michael E. Crenshaw, Michael Scalora, Charles M. Bowden
  • Patent number: 5253311
    Abstract: Micromachined depressions are created at a surface of lithium crystal/wavide composite and suitable optical components are inserted into these depressions and precisely aligned with waveguides so that light can be coupled into and out of the waveguides without fiber pigtails. The optical components can be independent or be a part of a mating unit which may incorporate appropriate electronics to support the optical components. Instant invention produces an application-ready integrated optics chip without the necessity for labor-intensive pigtailing or for separate provision of supporting electronics after the user acquires commercially available lithium crystal/waveguide composite.
    Type: Grant
    Filed: November 2, 1992
    Date of Patent: October 12, 1993
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Albert K. Killen, Cassie M. Lofts
  • Patent number: 5227579
    Abstract: The booster motors, each attached to and surrounding a centerbody, are mully connected to each other via one or more hollow manifold legs through which propulsive gases flow freely. At a predetermined time, the manifold cutter receives a signal activating the cutter to sever the manifold leg. Upon severance, the cut manifold leg still attached to the booster acts as a nozzle by venting residual propulsive gases and thereby propelling the booster away from the centerbody.
    Type: Grant
    Filed: June 10, 1992
    Date of Patent: July 13, 1993
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: David A. Gibson, Charles S. Cornelius
  • Patent number: 5218165
    Abstract: Upon the occurrence of a preset event, compressed gas is released from a mber and travels to fill a bellows. The bellows inflates and provides the power to eject a force transfer strut from the cavity of one body. The strut being fixedly attached at one end to a second body, this ejection accomplishes the separation of the two bodies from each other.
    Type: Grant
    Filed: June 10, 1992
    Date of Patent: June 8, 1993
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Charles S. Cornelius, David A. Gibson, Stephen C. Cayson
  • Patent number: 5210417
    Abstract: A modulated Faraday rotation signal is produced by passing a linearly polarized laser beam through a semiconductor wafer sample in a modulated magnetic field that is induced in an electromagnet by a sine wave generator and driver coupled thereto. The rotation signal is normalized by dividing by a transmission signal produced by modulating the beam with a chopper that operates at a different frequency from the frequency of the driver. The result is a Faraday rotation measurement with high signal-to-noise ratio and compensation for laser drift in intensity.
    Type: Grant
    Filed: February 24, 1992
    Date of Patent: May 11, 1993
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: John A. Grisham, Frederick W. Clarke, Charles R. Christensen, John L. Stensby
  • Patent number: 5191392
    Abstract: The White Light Optical Fourier Transform Device comprises symmetrical wedges of uniaxial birefringent crystal placed on either side of a half-wave plate to induce an angle between the wavefronts of the polarized components of the beam travelling through the device. The wavefront tilt angle of the output beam is shown to be linearly proportional to the angle of incidence. This is sufficient to generate the necessary phase factor for a Fourier transform of the incident intensity image.
    Type: Grant
    Filed: September 9, 1991
    Date of Patent: March 2, 1993
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventor: John L. Johnson
  • Patent number: 5097139
    Abstract: Pivotable, reflective target elements are used to reflect infrared radiat from blackbody sources and transmit the radiation toward infrared-detecting device to test the capability of the device to detect patterns of infrared radiation under dynamic field environment.
    Type: Grant
    Filed: April 19, 1991
    Date of Patent: March 17, 1992
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventor: Joseph W. Foster
  • Patent number: 5064140
    Abstract: Van Atta array is used to receive a millimeter wave beam from a beam transmitter located in a missile in flight and retransmit the beam back to its source along its original optical path after the beam is phase conjugated and modulated at a tracking station by imparting to it missile guidance information. The missile extracts guidance information from the retransmitted beam and guides its trajectory closer to the course leading to the target.
    Type: Grant
    Filed: October 9, 1990
    Date of Patent: November 12, 1991
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: William C. Pittman, Walter E. Miller, Jr., Michael R. Christian
  • Patent number: 5060593
    Abstract: A device for applying adhesive onto a fiber, such as an optical fiber, is located between the fiber supply spool and rewinder and comprises a covered cup for holding liquid adhesive, and a drying chamber. The cup has first and second bores for passing the fiber therethrough and is suitably insulated from external temperature changes. The entrance of the drying chamber is coupled to a side of the cup so that it surrounds the second bore.
    Type: Grant
    Filed: June 25, 1990
    Date of Patent: October 29, 1991
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Paul B. Ruffin, Michael L. Steelman, Kenneth A. Corbett, Charles A. Mandy, Jr.
  • Patent number: 5059003
    Abstract: A block of composite material includes a dielectric material with a dielectric constant of .epsilon..sub.d =4.66 and which is at least 4 .mu.m thick and has electrically conductive microparticles randomly distributed throughout. The composite material exhibits an optical bistability without cavity feedback. The microparticles must be nearly uniform in size and of spherical diameter much smaller than the wavelength of light in the particle. The composite, when illuminated by laser light in the range of 500 nm and of varying intensity, becomes opaque at a critical input intensity and stays opaque until the input intensity reaches a certain level both below and above the intensity at which it initially became opaque. Thus the material behaves as an optical switch and a limiter.
    Type: Grant
    Filed: August 7, 1989
    Date of Patent: October 22, 1991
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Joseph W. Haus, Nauzer Kalyaniwalla, Ramarao Inguva, Charles M. Bowden
  • Patent number: 5041779
    Abstract: Utilizing the property of electro-optic crystal which changes its index of refraction in the presence of electric field, such a crystal is placed inside the resonant cavity of a Fabry-Perot type interferometer. Laser light travelling through the cavity and the crystal experiences modified optical path length in the presence of electric field. The fringe pattern at the focal plane is observed and used to detect and measure the ambient electric field.
    Type: Grant
    Filed: August 17, 1990
    Date of Patent: August 20, 1991
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventor: Walter L. Hales
  • Patent number: 5018447
    Abstract: An optically transparent cylinder having a hemispherical cavity at one end hereof and containing at least one light source and one light detector inside the hemispherical cavity utilizes the prismatic effect of the cylinder to locate an object in space. The light source and detector are located on a disk whose insertion depth into the cavity and tilt angle inside the cavity can be varied to control the sharpness, width and direction of the conical beam output from the cylinder, the beam searching the space for the location of the desired object.
    Type: Grant
    Filed: May 3, 1990
    Date of Patent: May 28, 1991
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Walter E. Miller, Jr., Robert R. Mitchell, Donald E. Lovelace
  • Patent number: 5009373
    Abstract: In precision winding of fibers onto a bobbin mounted on a mandrel, a suity positioned circuit of lag angle detector, differentiator, threshold and status latch detect the occurrence of a crossover event while a suitably positioned circuit of angle counter, turn counter and data latch record the absolute mandrel angle and the number of complete revolutions of the mandrel at each occurrence of the crossover event. A computer coupled to the status latch and data latch graphically depicts the absolute mandrel angle versus the number of revolutions at the time of each crossover occurrence. This graphic depiction simulates the crossover pattern, thus making it possible to observe the pattern without stopping the winding process to inspect the pattern visually.
    Type: Grant
    Filed: April 16, 1990
    Date of Patent: April 23, 1991
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventor: Troy I. Hester
  • Patent number: 4968126
    Abstract: An all-optical polar transform device transforms an image in rectangular rdinates into an image in polar coordinates by reflecting an input image-containing beam from a series of suitably positioned reflective surfaces and finally transmits the beam out as an output beam containing the transformed image.
    Type: Grant
    Filed: February 20, 1990
    Date of Patent: November 6, 1990
    Assignee: The United States of America as represented by the secretary of the Army
    Inventor: John L. Johnson