Patents Represented by Attorney, Agent or Law Firm Gary R. Drew
  • Patent number: 6678351
    Abstract: A method of imaging an object by generating laser pulses with a short-pulse, high-power laser. When the laser pulse strikes a conductive target, bremsstrahlung radiation is generated such that hard ballistic high-energy electrons are formed to penetrate an object. A detector on the opposite side of the object detects these electrons. Since laser pulses are used to form the hard x-rays, multiple pulses can be used to image an object in motion, such as an exploding or compressing object, by using time gated detectors. Furthermore, the laser pulses can be directed down different tubes using mirrors and filters so that each laser pulse will image a different portion of the object.
    Type: Grant
    Filed: May 4, 2000
    Date of Patent: January 13, 2004
    Assignee: The United States of America as represented by the United States Department of Energy
    Inventors: Michael D. Perry, Joseph A. Sefcik
  • Patent number: 6306020
    Abstract: A slurry system draws slurry from a slurry tank via one of several intake pipes, where each pipe has an intake opening at a different depth in the slurry. The slurry is returned to the slurry tank via a bypass pipe in order to continue the agitation of the slurry. The slurry is then diverted to a delivery pipe, which supplies slurry to a polisher. The flow of slurry in the bypass pipe is stopped in order for the slurry in the slurry tank to begin to settle. As the polishing continues, slurry is removed from shallower depths in order to pull finer grit from the slurry. When the polishing is complete, the flow in the delivery pipe is ceased. The flow of slurry in the bypass pipe is resumed to start agitating the slurry. In another embodiment, the multiple intake pipes are replaced by a single adjustable pipe. As the slurry is settling, the pipe is moved upward to remove the finer grit near the top of the slurry tank as the polishing process continues.
    Type: Grant
    Filed: March 10, 2000
    Date of Patent: October 23, 2001
    Assignee: The United States of America as represented by the Department of Energy
    Inventors: P. Paul Hed, Baruch A. Fuchs
  • Patent number: 6141362
    Abstract: A pulsed laser is provided wherein the B-integral accumulated in the laser pulse is reduced using a semiconductor wafer. A laser pulse is generated by a laser pulse source. The laser pulse passes through a semiconductor wafer that has a negative nonlinear index of refraction. Thus, the laser pulse accumulates a negative B-integral. The laser pulse is then fed into a laser amplification medium, which has a positive nonlinear index of refraction. The laser pulse may make a plurality of passes through the laser amplification medium and accumulate a positive B-integral during a positive non-linear phase change. The semiconductor and laser pulse wavelength are chosen such that the negative B-integral accumulated in the semiconductor wafer substantially cancels the positive B-integral accumulated in the laser amplification medium. There may be additional accumulation of positive B-integral if the laser pulse passes through additional optical mediums such as a lens or glass plates.
    Type: Grant
    Filed: June 5, 1998
    Date of Patent: October 31, 2000
    Assignee: The United States of America as represented by the United States Department of Energy
    Inventors: David D. Meyerhofer, Oleg A. Konoplev
  • Patent number: 6099389
    Abstract: A method for forming optical parts used in laser optical systems such as high energy lasers, high average power lasers, semiconductor capital equipment and medical devices. The optical parts will not damage during the operation of high power lasers in the ultra-violet light range. A blank is first ground using a fixed abrasive grinding method to remove the subsurface damage formed during the fabrication of the blank. The next step grinds and polishes the edges and forms bevels to reduce the amount of fused-glass contaminants in the subsequent steps. A loose abrasive grind removes the subsurface damage formed during the fixed abrasive or "blanchard" removal process. After repolishing the bevels and performing an optional fluoride etch, the surface of the blank is polished using a zirconia slurry. Any subsurface damage formed during the loose abrasive grind will be removed during this zirconia polish. A post polish etch may be performed to remove any redeposited contaminants.
    Type: Grant
    Filed: October 5, 1998
    Date of Patent: August 8, 2000
    Assignee: The United States of America as represented by the United States Department of Energy
    Inventors: Michael A. Nichols, David M. Aikens, David W. Camp, Ian M. Thomas, Craig Kiikka, Lynn M. Sheehan, Mark R. Kozlowski
  • Patent number: 5824602
    Abstract: A helicon plasma source is controlled by varying the axial magnetic field or rf power controlling the formation of the helicon wave. An energetic electron current is carried on the wave when the magnetic field is 90 G; but there is minimal energetic electron current when the magnetic field is 100 G in one particular plasma source. Similar performance can be expected from other helicon sources by properly adjusting the magnetic field and power to the particular geometry. This control for adjusting the production of energetic electrons can be used in the semiconductor and thin-film manufacture process. By applying energetic electrons to the insulator layer, such as silicon oxide, etching ions are attracted to the insulator layer and bombard the insulator layer at higher energy than areas that have not accumulated the energetic electrons. Thus, silicon and metal layers, which can neutralize the energetic electron currents will etch at a slower or non-existent rate.
    Type: Grant
    Filed: October 21, 1996
    Date of Patent: October 20, 1998
    Assignee: The United States of America as represented by the United States Department of Energy
    Inventors: Arthur W. Molvik, Albert R. Ellingboe
  • Patent number: 5756925
    Abstract: A precision flyer initiator forms a substantially spherical detonation wave in a high explosive (HE) pellet. An explosive driver, such as a detonating cord, a wire bridge circuit or a small explosive, is detonated. A flyer material is sandwiched between the explosive driver and an end of a barrel that contains an inner channel. A projectile or "flyer" is sheared from the flyer material by the force of the explosive driver and projected through the inner channel. The flyer than strikes the HE pellet, which is supported above a second end of the barrel by a spacer ring. A gap or shock decoupling material delays the shock wave in the barrel from predetonating the HE pellet before the flyer. A spherical detonation wave is formed in the HE pellet. Thus, a shock wave traveling through the barrel fails to reach the HE pellet before the flyer strikes the HE pellet. The precision flyer initiator can be used in mining devices, well-drilling devices and anti-tank devices.
    Type: Grant
    Filed: May 23, 1996
    Date of Patent: May 26, 1998
    Assignee: The United States of America as represented by the United States Department of Energy
    Inventors: Alan M. Frank, Ronald S. Lee
  • Patent number: 5576561
    Abstract: A barrier at a uniform depth for an entire wafer is used to produce imaging devices less susceptible to noise pulses produced by the passage of ionizing radiation. The barrier prevents charge created in the bulk silicon of a CCD detector or a semiconductor logic or memory device from entering the collection volume of each pixel in the imaging device. The charge barrier is a physical barrier, a potential barrier, or a combination of both. The physical barrier is formed by an SiO.sub.2 insulator. The potential barrier is formed by increasing the concentration of majority carriers (holes) to combine with the electron's generated by the ionizing radiation. A manufacturer of CCD imaging devices can produce radiation-tolerant devices by merely changing the wafer type fed into his process stream from a standard wafer to one possessing a barrier beneath its surface, thus introducing a very small added cost to his production cost. An effective barrier type is an SiO.sub.2 layer.
    Type: Grant
    Filed: August 18, 1994
    Date of Patent: November 19, 1996
    Assignee: United States Department of Energy
    Inventors: Nicholas J. Colella, Joseph R. Kimbrough