Patents by Inventor John M. Sandrik

John M. Sandrik 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: 5530735
    Abstract: A CT system includes a pair of detectors in its detector array which measure x-ray intensity from a source after passing through a differential x-ray filter. The ratio of the signals produced by these two detector elements are input to a KV calculator which produces a signal indicative of x-ray tube voltage.
    Type: Grant
    Filed: December 27, 1994
    Date of Patent: June 25, 1996
    Assignee: General electric Company
    Inventors: Michael F. Gard, John M. Sandrik
  • Patent number: 5400387
    Abstract: A CT system includes a pair of detectors in its detector array which measure x-ray intensity from a source after passing through a differential x-ray filter. The ratio of the signals produced by these two detector elements are input to a KV calculator which produces a signal indicative of x-ray tube voltage.
    Type: Grant
    Filed: March 1, 1994
    Date of Patent: March 21, 1995
    Assignee: General Electric Company
    Inventors: Michael F. Gard, John M. Sandrik
  • Patent number: 5321272
    Abstract: An x-ray beam stop for high energy x-ray devices comprises a laminate structure of multiple layers of different Z materials which may include lead (Pb) and arranged in progressive Z order for a predetermined x-ray detector orientation.
    Type: Grant
    Filed: December 18, 1992
    Date of Patent: June 14, 1994
    Assignee: General Electric Company
    Inventors: Paul R. Granfors, John M. Sandrik
  • Patent number: 5236363
    Abstract: A phantom for simulating a patient during an X-ray exam that involves introducing a high contrast material into the patient. The phantom comprises a base and a first contrast element. The first contrast element is disposed within the base and has an X-ray attenuation greater than that of the base. The contrast ratio of the first contrast element to the base is approximately 50. In one embodiment of the phantom, the first contrast element contains iodine. In another embodiment, the base has a shape which occupies the entire field of view of the X-ray exam and the first contrast element is positioned substantially in the center of the field of view. In yet another embodiment of the phantom, a second contrast element is disposed within the base and has a contrast ratio to the base of approximately 1.5.
    Type: Grant
    Filed: August 9, 1991
    Date of Patent: August 17, 1993
    Assignee: General Electric Company
    Inventors: John M. Sandrik, Gordon M. Geiger
  • Patent number: 4852139
    Abstract: A method and apparatus for use in a medical x-ray imaging system of the type including an x-ray source, an image intensifier tube for providing a momentary x-ray image of a patient exposed to x-rays and a video camera having video processing circuits for providing signals representative of a video image of the x-ray image on the intensifier tube to a video monitor provides a flickerless image presentation on the video monitor when the x-ray exposure repetition rate is different from the field scan rate of the video camera. The apparatus enables this result by sensing initiation of a first x-ray exposure and setting the amplification of the video processing circuits to a first value for obtaining a suitable presentation of the image. The apparatus then scans the image on the video camera to provide a first field of image presentation to the video monitor with the amplification set at the first value.
    Type: Grant
    Filed: December 2, 1985
    Date of Patent: July 25, 1989
    Assignee: General Electric Company
    Inventors: John M. Sandrik, Rowland F. Saunders
  • Patent number: 4603428
    Abstract: X-ray energy-difference images are obtained simultaneously by exposing a body to a broad energy spectrum x-ray beam while a radiographic film package is disposed between front and rear x-ray intensifying screens. The film package has two superimposed films with a light-opaque sheet between them. The front screen, on which the polyenergetic image beam emerging from the body is incident, is excited to luminescence by x-ray photons predominantly in one energy band and the rear screen is excited predominantly by photons in another band. The light opaque sheet preferably contains x-ray filter material for additional filtering of photons to increase the fraction of photons at said other band to which the rear screen is sensitive. A shadowgraph of a marker is formed on the film emulsions during x-ray exposure to aid in matching congruent picture elements on each film when the developed films are being read out to obtain signals corresponding to their intensities.
    Type: Grant
    Filed: January 4, 1985
    Date of Patent: July 29, 1986
    Assignee: General Electric Company
    Inventors: John M. Sandrik, Norbert J. Pelc
  • Patent number: 4513078
    Abstract: X-ray energy-difference images are obtained simultaneously by exposing a body to a broad energy spectrum X-ray beam while a radiographic film package is disposed between front and rear X-ray intensifying screens. The film package has two superimposed films with a light-opaque sheet between them. The front screen, on which the polyenergetic image beam emerging from the body is incident, is excited to luminescence by X-ray photons predominantly in one energy band and the rear screen is excited predominantly by photons in another band. The light opaque sheet preferably contains X-ray filter material for additional filtering of photons to increase the fraction of photons at said other band to which the rear screen is sensitive. A shadowgraph of a marker is formed on the film emulsions during X-ray exposure to aid in matching congruent picture elements on each film when the developed films are being read out to obtain signals corresponding to their intensities.
    Type: Grant
    Filed: October 13, 1983
    Date of Patent: April 23, 1985
    Assignee: General Electric Company
    Inventors: John M. Sandrik, Norbert J. Pelc