Patents by Inventor Gregory Um

Gregory Um has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 5710657
    Abstract: A thin film actuated mirror is disclosed having a substrate, a deformable structure mounted to the substrate, and a mirror surface interconnected to the deformable structure such that the mirror surface tilts in response to the deformation of the deformable material layer. The deformation occurs due to the effective strain gradient across the monomorph thickness which is accomplished by varying the electric field across the thickness or the strain parameter across the thickness. The deformable structure includes an active material layer fabricated from a semi-conductive ferroelectric ceramic material and two metal electrodes, each of the electrodes being mounted on opposing surfaces of the active material layer, wherein an electrical signal applied across the active material layer between the electrodes causes deformation of the active material layer.
    Type: Grant
    Filed: April 17, 1995
    Date of Patent: January 20, 1998
    Assignee: Aura Systems, Inc.
    Inventor: Gregory Um
  • Patent number: 5689380
    Abstract: A thin film actuated mirror for an actuated mirror array includes a pedestal, a piezoelectric structure mounted to the pedestal, and a mirror surface interconnected to the piezoelectric structure such that the mirror surface tilts in response to the deformation of the piezoelectric material layer. The pedestal includes a first pedestal section and a second pedestal section, and the piezoelectric structure is divided into a first portion and a second portion. The piezoelectric structure includes a piezoelectric material layer having two opposing surfaces, and two metal electrodes, the electrodes being mounted on opposing surfaces of the piezoelectric material. The piezoelectric structure first portion is mounted to the first pedestal section at a proximal end of the piezoelectric structure and the second portion is mounted to the second pedestal section at a distal end of the piezoelectric structure.
    Type: Grant
    Filed: April 17, 1995
    Date of Patent: November 18, 1997
    Assignee: Aura Systems, Inc.
    Inventor: Gregory Um
  • Patent number: 5616982
    Abstract: An actuator for tilting the plane of an object includes a substrate and a pair of piezoelectric material members. Each of the piezoelectric members has a top surface, a bottom surface, a first side surface and a second side surface. The bottom surface is mounted to the substrate, and the first side surfaces of each of the members are affixed to each other and electrically connected in common. One of the piezoelectric material members further has a polarization selected so that a voltage applied between the first side surface and the second side surface thereof causes the piezoelectric material member to either contract or expand between the top surface and said bottom surface, depending on the polarity of the voltage. The object is mounted to the top surface of each of the piezoelectric material members so that when a voltage is applied to one of the piezoelectric material members, the object either tilts toward or away from that member, depending on the polarity of the voltage.
    Type: Grant
    Filed: March 25, 1996
    Date of Patent: April 1, 1997
    Assignee: Aura Systems, Inc.
    Inventors: Gregory Um, Andrei Szilagyi
  • Patent number: 5589084
    Abstract: A thin film actuated mirror for an actuated mirror array includes a pedestal and at least piezoelectric structure cantilevered from the pedestal. The piezoelectric structure includes a layer of piezoelectric material having two opposing surfaces. Each of two metal electrodes are mounted on a respective one of the opposing surfaces of the piezoelectric material layer. An electrical signal is applied across the piezoelectric material, between the electrodes, causing deformation of the piezoelectric material. The thin film actuated mirror further includes a mirror surface interconnected to the piezoelectric material layer such that the mirror surface deforms in response to the deformation of the piezoelectric material layer.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: December 31, 1996
    Assignees: Daewoo Electronics Co. Ltd., Aura Systems, Inc.
    Inventors: Jeong B. Ji, Gregory Um
  • Patent number: 5481396
    Abstract: A thin film actuated mirror for an actuated mirror array includes a pedestal and at least piezoelectric structure cantilevered from the pedestal. The piezoelectric structure includes a layer of piezoelectric material having two opposing surfaces. Each of two metal electrodes are mounted on a respective one of the opposing surfaces of the piezoelectric material layer. An electrical signal is applied across the piezoelectric material, between the electrodes, causing deformation of the piezoelectric material. The thin film actuated mirror further includes a mirror surface interconnected to the piezoelectric material layer such that the mirror surface deforms in response to the deformation of the piezoelectric material layer.
    Type: Grant
    Filed: February 23, 1994
    Date of Patent: January 2, 1996
    Assignee: Aura Systems, Inc.
    Inventors: Jeong B. Ji, Gregory Um
  • Patent number: 5260798
    Abstract: An apparatus to modulate the intensity of a pixel displayed on a screen focused optical energy from a broadband source onto a reflective first face of a planar member. The first face is disposed in said first propagation path at a selected angle thereto to direct optical energy along a second propagation path. A planar mirror is disposed in the second propagation path. The plane of the mirror is actuatable to orientate the mirror within a range of angles to said second propagation path between a first angle limit and a second angle limit. A second focusing lens disposed in the second propagation path to focus optical energy reflected from the first face onto the mirror.
    Type: Grant
    Filed: May 18, 1992
    Date of Patent: November 9, 1993
    Assignee: Aura Systems, Inc.
    Inventors: Gregory Um, Andrei Szilagyi
  • Patent number: 5245369
    Abstract: Optical energy from a broadband source is focused on an aperture in an opaque member. The energy exiting the aperture is received off axis by a parabolic mirror which collimates the energy. The collimated energy is reflected from each planar mirror of an actuated mirror array. The reflected energy from the mirror array is re-reflected to the aperture by the parabolic mirror. The orientation of each planar mirror determines the flux which passes through the aperture or is reflected by a reflective face of the opaque member. The energy reflected from this face which is derived from each mirror corresponds to the flux intensity for a corresponding pixel. This energy may then be focused on a screen to display the scene.
    Type: Grant
    Filed: October 18, 1991
    Date of Patent: September 14, 1993
    Assignee: Aura Systems, Inc.
    Inventors: Gregory Um, Yeon H. Lee
  • Patent number: 5185660
    Abstract: A television display apparatus wherein a white light source emits 9a beam onto a plurality of dichroic mirrors which split the beam into three beams of the primary colors, then reflects the three primary beams onto three deformable reflective surfaces, which again reflect the beams through slits in a non-reflective surface, thereby modulating the intensity of the beams. The amount of light passing through the slits is horizontally scanned by one surface of a rotating polygonal mirror, then passes through collimating and projection lenses and onto a screen.
    Type: Grant
    Filed: February 22, 1990
    Date of Patent: February 9, 1993
    Assignee: Aura Systems, Inc.
    Inventor: Gregory Um
  • Patent number: 5175465
    Abstract: An actuator for tilting the plane of an object is constructed from a stack of piezoelectric or electrostrictive members. First alternate interstices between the members are filled with a first conductive material, except that a first gap remains between the material and one side of the stack. Similarly, second alternate interstices between the members are filled with a second conductive material, except that a second gap remains between the material and an opposite side of the stack. The first gap and the second gap have unequal depth into the stack. The first material in the first interstices is coupled in common and the second material in the second interstices is coupled in common. A voltage applied between the first material and the second material will thereby cause the stack to bend, thereby tilting the plane of the op of the stack.
    Type: Grant
    Filed: October 18, 1991
    Date of Patent: December 29, 1992
    Assignee: Aura Systems, Inc.
    Inventors: Gregory Um, Andrei Szilagyi
  • Patent number: 5159225
    Abstract: A piezoelectric actuator includes a pair of piezoelectric members which are oriented to shear laterally toward each other in the presence of an applied voltage. A hinge having translational members (which act similarly to a rack) and a rotating member (which acts similarly to a pinion) is attached to the top of the piezoelectric members with one translational attached to a respective one of the piezoelectric members. A driven member attached radially outward from the rotating member will then move through an arc when the piezoelectric members laterally shear. An object, such as a mirror, when carried by the distal end of the driven member, will then be actuated.
    Type: Grant
    Filed: October 18, 1991
    Date of Patent: October 27, 1992
    Assignee: Aura Systems, Inc.
    Inventor: Gregory Um
  • Patent number: 5150205
    Abstract: A television display apparatus wherein a white light source emits a beam onto a plurality of dichroic mirrors which split the beam into three beams of the primary colors, then reflects the three primary beams onto three deformable reflective surfaces, which again reflect the beams through slits in a non-reflective surface, thereby modulating the intensity of the beams. The amount of light passing through the slits is horizontally scanned by one surface of a rotating polygonal mirror, then passes through collimating and projection lenses and onto a screen.
    Type: Grant
    Filed: November 1, 1989
    Date of Patent: September 22, 1992
    Assignee: Aura Systems, Inc.
    Inventors: Gregory Um, Andrei Szilagyi
  • Patent number: 5126836
    Abstract: A television display apparatus wherein a white light source emits a beam onto a plurality of dichroic mirrors which split the beam into three beams of the primary colors, then reflects the three primary beams onto three deformable reflective surfaces, which again reflect the beams through slits in a non-reflective surface, thereby modulating the intensity of the beams. The amount of light passing through the slits is horizontally scanned by one surface of a rotating polygonal mirror, then passes through collimating and projection lenses and onto a screen.
    Type: Grant
    Filed: December 11, 1989
    Date of Patent: June 30, 1992
    Assignee: Aura Systems, Inc.
    Inventor: Gregory Um
  • Patent number: 5085497
    Abstract: A method for fabricating an array of mirrors for an optical projection system. This method comprises the steps of forming an array of holes between a top surface and a bottom surface on an electrically insulated substrate. These holes are then filled with an electrically conductive material. Another step in this method includes mounting a plurality of piezoelectric pedestals on the top surface of the substrate wherein each of the pedestals are disposed over a respective hole so that the first face of each of the pedestals is electrically connected to the conductive material in the respective holes. A plurality of mirrors are then mounted on the pedestals wherein each of the mirrors is disposed on at least one of the pedestals. After the mirrors are mounted the second face of each pedestal is electrically connected to a common circuit node.
    Type: Grant
    Filed: March 16, 1990
    Date of Patent: February 4, 1992
    Assignee: Aura Systems, Inc.
    Inventors: Gregory Um, Andrei Szilagyi
  • Patent number: 5035475
    Abstract: A video display system includes a source of optical energy, a beam splitter, a baffle, an MxN array of mirrors and a screen. The source develops the first light beam along a first propagation path. The beam splitter is disposed in this first propagation path. The beam splitter is positioned to split the optical energy of the first light beam to develop a second light beam along a second propagation path. The baffle has a first face, a second face and a row of parallel slits. The slits are open between the first face and the second face and may extend either vertically or horizontally across each face of the baffle. Accordingly, there are either M rows or N columns of slits. The baffle is disposed in the second propagation path so that the second light beam illuminates the first face and passes through the slits to exit from the second face as a plurality of planar light beams along the second propagation path. The mirror array is disposed in a facing relationship to the second face of the baffle.
    Type: Grant
    Filed: March 15, 1990
    Date of Patent: July 30, 1991
    Assignee: Aura Systems, Inc.
    Inventors: Yeon H. Lee, Gregory Um
  • Patent number: 5032906
    Abstract: A scene projector is calibrated by providing a look-up table for intensity adjustment values of each pixel of the displayed frame. The look-up table is formed by calculating a ratio of measured intensity of each pixel to the intensity of the pixel of minimum intensity when power and scene modulation controls are at maximum. Power modulator control response and scene modulator control response curves are generated, and a black body calibration is performed to define the relation between black body temperature, power modulator and scene modulator settings. Power modulator control settings are determined for each of a number of selected black body temperatures, and a scene modulator setting is determined that is required to obtain a proper black body temperature. These values are stored in a second table and combined with intensity value corrections from the intensity value table to modify image data.
    Type: Grant
    Filed: July 12, 1989
    Date of Patent: July 16, 1991
    Assignee: Aura Systems, Inc.
    Inventor: Gregory Um
  • Patent number: 4979789
    Abstract: A scene projector displays an image as M by N array of pixels. The scene projector includes a plurality of optical guided wave modulators. The modulators each have an optical input, and optical output and an electrical input. The optical output of each of the modulators forms a corresponding one of the pixels. The optical input of each of the modulators is adapted to be uniformly illuminated. The scene projector further applies a selected voltage to the electrical input of each of the modulators. This voltage is selected commensurately with a predetermined intensity of output optical energy at the corresponding pixel.
    Type: Grant
    Filed: June 2, 1989
    Date of Patent: December 25, 1990
    Assignee: Aura Systems, Inc.
    Inventor: Gregory Um