Patents by Inventor Robert E. Alvarez

Robert E. Alvarez 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: 8929508
    Abstract: An apparatus or method for providing information about an object from x-ray radiation transmitted through the object. An embodiment comprises an x-ray source (10) positioned on one side of an object (50) an x-ray detector (102) positioned on the opposite side, and means for computing two or more information signals, which are substantially the line integrals of the basis set coefficients of the x-ray attenuation coefficient from the x-ray photons transmitted through said object at three or more regions of the x-ray energy spectrum. In one embodiment the means for computing the two or more information signals comprises a linear maximum likelihood estimator (122), a correction processor (142) to compute a correction to the linear maximum likelihood estimate (132), and an adder (152) to add the estimate and the correction to produce the two or more information signals (154).
    Type: Grant
    Filed: April 17, 2012
    Date of Patent: January 6, 2015
    Inventor: Robert E. Alvarez
  • Patent number: 6181764
    Abstract: An x-ray imaging system capable of local focussing to any depth is disclosed. According to an aspect, the invention comprises a method of generating a volume of data comprising image information for a plurality of depths with an object under investigation, and selecting data from the volume of data to generate a display image.
    Type: Grant
    Filed: October 6, 1998
    Date of Patent: January 30, 2001
    Assignee: Cardiac Mariners, Inc.
    Inventors: Edward G. Solomon, Robert E. Melen, Robert E. Alvarez, Daniel J. Rachlin
  • Patent number: 6178223
    Abstract: An image reconstruction system that can generate an accurate image representation of structure and regions within an object is disclosed. An aspect of the invention comprises a processor that is configured to receive x-ray transmissive information for an object to generate image pixel information for a plurality of depths within the object. The display image comprises selected image pixel information corresponding to image pixels at a plurality of depths within the object.
    Type: Grant
    Filed: October 6, 1998
    Date of Patent: January 23, 2001
    Assignee: Cardiac Mariners, Inc.
    Inventors: Edward G. Solomon, Robert E. Melen, Augustus P. Lowell, Robert E. Alvarez, Daniel J. Rachlin
  • Patent number: 5289012
    Abstract: Multiple x-ray images are encoded onto a single storage phosphor screen detector for later scanning, processing, and viewing. The x-ray images are encoded using spatial frequency multiplexing onto high frequency carriers. The encoding process relies only on light with no mechanical motion. The light erases selected portions of the image data but leaves sufficient information to reconstruct the original images. The reconstruction process relies on conventional sampling theory with the additional step of solving a system of equations for the individual x-ray image information.
    Type: Grant
    Filed: April 30, 1992
    Date of Patent: February 22, 1994
    Inventor: Robert E. Alvarez
  • Patent number: 5221843
    Abstract: An apparatus and method for energy selective x-ray image detection. A source produces two fluxes of x-ray radiation with two different energy spectra. The fluxes are sequentially incident on the subject then on two layered planar detectors with control means. Examples of planar detectors are stimulable phosphor screens or intensifying screen/photographic film detectors. Examples of control means are visible light sources or electric generators with stimulable phosphor screens or light valves with intensifying screen/film detectors. A sequencer uses control means to selectively enhance the response of a predetermined detector to corresponding sequential radiation flux. The predetermined response can be chosen to enhance the inherent energy selectivity of the layered detector e.g. the first detector preferentially responds to low energy while the second detector preferentially responds to high energy x-ray photons.
    Type: Grant
    Filed: April 23, 1992
    Date of Patent: June 22, 1993
    Inventor: Robert E. Alvarez
  • Patent number: 4413353
    Abstract: X-ray information is encoded onto photographic film by placing an optical grating between the light-emitting scintillating screen and the photographic emulsion. Information at different energies is encoded by displacing the grating between exposures or by using static gratings with an energy-selective dual screen.
    Type: Grant
    Filed: September 3, 1981
    Date of Patent: November 1, 1983
    Inventors: Albert Macovski, Bruno Strul, Robert E. Alvarez
  • Patent number: 4029963
    Abstract: Projection measurements are made of the transmitted x-ray beam in low and high energy regions. These are combined in a non-linear processor to produce atomic-number-dependent and density-dependent projection information. This information is used to provide cross-sectional images which are free of spectral-shift artifacts and completely define the specific material properties.
    Type: Grant
    Filed: July 30, 1976
    Date of Patent: June 14, 1977
    Assignee: The Board of Trustees of Leland Stanford Junior University
    Inventors: Robert E. Alvarez, Albert Macovski