Patents by Inventor Randolph F. Wojcik

Randolph F. Wojcik 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: 6740859
    Abstract: A readout circuit for an imaging detector that improves resolution and increases field of view in a display compared to traditional readout circuits. The readout circuit comprises two or more amplifiers that receive a row or column of outputs from the imaging detector. Subtraction circuitry, included in the readout circuit, receives the signals from the amplifiers, determines a fractional value of the sum of the signals, and subtracts the fractional value from each signal thereby producing both positive and negative signals. A rail to rail amplifier operating from a signale voltage supply eliminates one polarity of the signals making the signals unipolar. A combining circuit receives the unipolar signals and combines them to produce two readout circuit outputs that are transmitted to a computer to be displayed.
    Type: Grant
    Filed: August 6, 2002
    Date of Patent: May 25, 2004
    Assignee: Southeastern Univ. Research Assn., Inc.
    Inventors: Randolph F. Wojcik, Vladimir E. Popov
  • Patent number: 6271525
    Abstract: A gamma camera comprising essentially and in order from the front outer or gamma ray impinging surface: 1) a collimator, 2) a scintillator layer, 3) a light guide, 4) an array of position sensitive, high resolution photomultiplier tubes, and 5) printed circuitry for receipt of the output of the photomultipliers. There is also described, a system wherein the output supplied by the high resolution, position sensitive photomultipiler tubes is communicated to: a) a digitizer and b) a computer where it is processed using advanced image processing techniques and a specific algorithm to calculate the center of gravity of any abnormality observed during imaging, and c) optional image display and telecommunications ports.
    Type: Grant
    Filed: September 23, 1998
    Date of Patent: August 7, 2001
    Assignee: Southeastern University Research Assn.
    Inventors: Stanislaw Majewski, Andrew G. Weisenberger, Randolph F. Wojcik
  • Patent number: 5864141
    Abstract: A high resolution gamma ray imaging device includes an aluminum housing, a lead screen collimator at an opened end of the housing, a crystal scintillator array mounted behind the lead screen collimator, a foam layer between the lead screen collimator and the crystal scintillator array, a photomultiplier window coupled to the crystal with optical coupling grease, a photomultiplier having a dynode chain body and a base voltage divider with anodes, anode wire amplifiers each connected to four anodes and a multi pin connector having pin connections to each anode wire amplifier. In one embodiment the crystal scintillator array includes a yttrium aluminum perovskite (YAP) crystal array. In an alternate embodiment, the crystal scintillator array includes a gadolinium oxyorthosilicate (GSO) crystal array.
    Type: Grant
    Filed: July 23, 1997
    Date of Patent: January 26, 1999
    Assignee: Southeastern Univ. Research Assn.
    Inventors: Stanislaw Majewski, Andrew G. Weisenberger, Randolph F. Wojcik, Daniela Steinbach
  • Patent number: 5799124
    Abstract: The present invention comprises an illumination system for specialized decorative lighting including a light source, a flexible plastic tube sheath for distributing the light to a remote location, a transparent liquid core filling the tube that has an index of refraction greater than that of the plastic tube and an arrangement where light coupled from the light source is caused to leak from the liquid light guide at desired locations for the purposes of specialized lighting, such as underwater illumination in swimming pools.
    Type: Grant
    Filed: May 15, 1996
    Date of Patent: August 25, 1998
    Assignee: Southeastern Univ. Research Assn., Inc.
    Inventors: Carl J. Zorn, Brian J. Kross, Stanislaw Majewski, Randolph F. Wojcik
  • Patent number: 5742660
    Abstract: A multiple x-ray energy level imaging system includes a scanning x-ray beam and two detector design having a first low x-ray energy sensitive detector and a second high x-ray energy sensitive detector. The low x-ray energy detector is placed next to or in front of the high x-ray energy detector. The low energy sensitive detector has small stopping power for x-rays. The lower energy x-rays are absorbed and converted into electrical signals while the majority of the higher energy x-rays pass through undetected. The high energy sensitive detector has a large stopping power for x-rays as well as it having a filter placed between it and the object to absorb the lower energy x-rays. In a second embodiment; a single energy sensitive detector is provided which provides an output signal proportional to the amount of energy in each individual x-ray it absorbed. It can then have an electronic threshold or thresholds set to select two or more energy ranges for the images.
    Type: Grant
    Filed: January 10, 1997
    Date of Patent: April 21, 1998
    Assignee: Southeastern Universities Research Association, Inc.
    Inventors: Stanislaw Majewski, Randolph F. Wojcik