Patents Represented by Attorney Michael P. Dunnam
  • Patent number: 5917190
    Abstract: Imaging tumors using diffuse light. An imaging system includes a source of diffuse light for generating oscillatory diffuse photon density waves to illuminate an object, a detector for detecting diffuse photon density waves interacting with the object, and a computer interfaced with the detector for processing data corresponding to the photon density waves detected to determine at least a position of the object. In one embodiment, the turbid medium and the object have associated therewith at least one diffusion coefficient and the diffuse photon density waves which illuminate the object refract around the object as a result of their interaction with it, thereby producing a distorted wavefront that allows the computer to construct an image of the object. In another embodiment, a fluorescent object produces re-radiated diffuse photon density waves which allow the object to be imaged.
    Type: Grant
    Filed: July 25, 1996
    Date of Patent: June 29, 1999
    Assignee: Trustees of the University of Pennsylvania
    Inventors: Arjun G. Yodh, Britton Chance, David A. Boas, Maureen O'Leary
  • Patent number: 5790941
    Abstract: A method for reducing power consumption in a cellular telephone by placing the receiver in a sleep mode when it is determined that the received signal has a sufficiently high quality. The duration of the sleep mode is extended by eliminating the need to resynchronize the receiver clock to the transmitter clock using dotting sequence and synchronizing data in the transmitted control data received after a sleep cycle. This is accomplished by resynchronizing the phase of the symbol clock to the phase of the transmitter clock after a sleep cycle utilizing the respective phase relationships to a low frequency, low power maintenance clock in the receiver which maintains time (and hence edge information) during the sleep mode until reception of the next data frame must begin. The maintenance clock is preferably an off-the-shelf oscillator of the type used in wrist watches.
    Type: Grant
    Filed: April 10, 1995
    Date of Patent: August 4, 1998
    Assignee: Pacific Communication Sciences, Inc.
    Inventor: George M. Peponides
  • Patent number: 5646742
    Abstract: A system for printing an image onto a substrate includes a print controller that determines a difference in intended color intensity between a first pixel and a second pixel; adjusts the intended color intensity of the first pixel based on the determined difference; and deposits a colorant onto the substrate at the first pixel at the adjusted intended intensity, so as to enhance the appearance of the image on the substrate. The current system has particular utility in enhancing the appearance of fine images such as one pixel wide, vertical and diagonal lines in a printing system which utilizes printhead heating elements that are larger in the vertical direction than in the horizontal direction.
    Type: Grant
    Filed: April 24, 1995
    Date of Patent: July 8, 1997
    Assignee: Tektronix, Inc.
    Inventors: Jeffery J. Clark, Brian G. Crosby, Bo Lewendal, Gregory P. Thornton
  • Patent number: 5146414
    Abstract: Method and apparatus for adapting the volumetric flow rate measurement system taught by Yelderman in U.S. Pat. No. 4,507,974 to clinical environments by reducing the effects of physiological noise. Signal processing techniques are used to characterize the background noise power spectrum of the system under test so that the effect of noise aberrations on the measured data may be eliminated and so that the predominant periodicities of the background noise spectra may be avoided. The invention further cross-correlates the input data of the system with the corresponding ouput data of the system to determine weighting values for each input frequency so that data collected at noisy frequencies is discounted. Low frequency noise or drift is also removed from the output signal by fitting the average of the output data to a quadratic function which is then subtracted from the original output signal, point by point.
    Type: Grant
    Filed: April 18, 1990
    Date of Patent: September 8, 1992
    Assignee: Interflo Medical, Inc.
    Inventors: Russel McKown, Mark Yelderman, Michael Quinn