Patents by Inventor Robert D. Meadows

Robert D. Meadows 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: 6319732
    Abstract: A method for controlling the temperature of a growing semitransparent layer (12) during a production deposition process on a major surface of a production wafer (14). During the production process heat is applied to the wafer by an intensity adjustable heat source (34) and the production wafer emits a broad spectrum of light. In the method a test deposition process is performed using a set of infrared wavelengths of the light emitted from a test wafer to determine a set of test parameter values including temperature values over time for the test growing layer. The production deposition process is then performed and the intensity of infrared light emissions from the wafer are measured to form a set of production infrared light intensity values at the same test run set of infrared wavelengths used in the test deposition.
    Type: Grant
    Filed: October 25, 1999
    Date of Patent: November 20, 2001
    Assignee: Sekidenko, Inc.
    Inventors: Ray Dils, Robert D. Meadows
  • Patent number: 5223784
    Abstract: A method and circuit for triggering an electronic instrument only once during a period of an input signal having multiple triggering events during that period. A signal applied to an electronic instrument, such as an oscilloscope, is acquired. Qualified triggering events occurring on the acquired signal are identified. A selected one of the qualified triggering events during the period of the applied signal causes a trigger signal output to occur, while other qualified triggering events are ignored. In the preferred embodiment a triggering event is qualified by a first comparator that compares the input signal to a first reference level and produces a predetermined logic level output if the input signal bears a predetermined relationship to the reference level. When a qualified triggering event occurs, a buffer amplifier applies the predetermined logic level to charge a capacitor, which thereafter stores some energy from the input signal and applies it to a comparator for a predetermined period of time.
    Type: Grant
    Filed: June 1, 1991
    Date of Patent: June 29, 1993
    Assignee: Tektronix, Inc.
    Inventors: Theodore G. Nelson, Calvin D. Diller, Robert D. Meadows
  • Patent number: 5053757
    Abstract: A touch panel has panel scanning signals selectively applied to the four sides of a touch sensing surface of the panel so as to establish alternating current voltage gradients in desired directions across the touch sensing surface. When the panel is touched, touch signals result and are utilized by a touch location circuit in determining the location of touch. The impedance touch current resulting from a user's touch may also be determined and used. The touch panel circuit automatically filters the touch signals to an extent which varies depending upon the rate of movement of touch from one location on the touch sensing surface to a subsequent location. Filtering is decreased with the increasing rates of movement. The touch panel thereby minimizes the effects of noise on touch location determination.
    Type: Grant
    Filed: December 27, 1989
    Date of Patent: October 1, 1991
    Assignee: Tektronix, Inc.
    Inventor: Robert D. Meadows
  • Patent number: 4962380
    Abstract: An apparatus and method for calibrating an interleaved digitizer includes a system oscillator for generating a master clock signal and two or more cascaded phase shifting circuits for producing clock signals that are phase shifted copies of the master clock signal. The calibrator further includes two or more A/D converters for digitizing the master clock signal at time intervals provided by the phase shifted clock signals to produce a digitized output. The digitized output is then stored in a memory. Once stored, the digitized output is compared to predetermined reference levels and the phase shift of the phase shifting circuits is appropriately adjusted as a function of the difference between the stored digitized output and the predetermined reference levels.
    Type: Grant
    Filed: September 21, 1989
    Date of Patent: October 9, 1990
    Assignee: Tektronix, Inc.
    Inventor: Robert D. Meadows
  • Patent number: 4939672
    Abstract: A display system comprises a data base memory for storing data representing a picture, a display device for displaying the picture, and manipulation means for causing the display device to display a cursor at a position which is under user control. The picture is composed of objects and each object is represented in the data base memory by a segment which represents both the object and the position of the object in the picture. A pointer, which divides the address domain of the display device into at least two regions, is generated. The manipulation means provides a signal which identifies the region of the pictures in which the cursor is positioned, and this signal is compared with the contents of the data base memory to facilitate selection of an object which lies in the identified region of the picture.
    Type: Grant
    Filed: November 9, 1987
    Date of Patent: July 3, 1990
    Assignee: Tektronix, Inc.
    Inventor: Robert D. Meadows
  • Patent number: 4916308
    Abstract: A flat panel liquid crystal display (12) with an integrated touch panel has a multitude of pixels (28) arranged in multiple columns and multiple rows. The pixels (28) of the first column (54) and last column (66), and of the first row (60) and of the last row (72) are controlled in conjunction with emitters (52, 58) and detectors (64, 70) with associated mirrors (74, 80, 82, 84) to create a sequence of light beams that extend across the display panel (12) in both the X and Y directions. Whenever a stylus (86) is placed near the display panel, two orthogonal light beams are interrupted corresponding to the X and Y positions of the stylus (86) relative to the display panel (12).
    Type: Grant
    Filed: October 17, 1988
    Date of Patent: April 10, 1990
    Assignee: Tektronix, Inc.
    Inventor: Robert D. Meadows
  • Patent number: 4853498
    Abstract: A capacitive touch panel system (10) having a faceplate (14) with an electrically conductive layer (20) of a consistent resistivity employs a position measurement apparatus (12) to generate an address signal indicative of a position (46) on the faceplate in contact with a stylus (48). The position measurement apparatus includes a position measurement signal source (62) that generates a square-wave measurement signal of substantially constant frequency and a preselected magnitude. The position measurement signal is applied to a first pair of opposed electrodes (36) and (40) and a second pair of opposed electrodes (38) and (42) positioned along respective side margins (26, 30, 28, and 32) of the faceplate. The resistivity of the conductive layer establishes effective resistances of R.sub.x and R.sub.y between the respective first and second pairs of electrodes.
    Type: Grant
    Filed: June 13, 1988
    Date of Patent: August 1, 1989
    Assignee: Tektronix, Inc.
    Inventors: Robert D. Meadows, Roger J. McCoy
  • Patent number: 4707845
    Abstract: A touch panel has panel scanning signals selectively applied to the four sides of a touch sensing surface of the panel so as to establish alternating current voltage gradients in desired directions across the touch sensing surface. When the panel is touched, touch signals result and are utilized by a touch location circuit in determining the location of touch. The impedence touch current resulting from a user's touch may also be determined and used. The touch panel circuit automatically compensates for any variations in touch signals which occur when the touch panel is untouched and automatically nulls the touch signals under such circumstances to enhance the accuracy of touch location determination.
    Type: Grant
    Filed: August 26, 1986
    Date of Patent: November 17, 1987
    Assignee: Tektronix, Inc.
    Inventors: Philip T. Krein, Robert D. Meadows, Bruce Murdock, Daniel G. Teichmer
  • Patent number: 4698461
    Abstract: A touch panel has panel scanning signals selectively applied to the four sides of a touch sensing surface of the panel so as to establish alternating current voltage gradients in desired directions across the touch sensing surface. When the panel is touched, touch signals result and are utilized by a touch location circuit in determining the location of touch. The impedence touch current resulting from a user's touch may also be determined and used. The touch panel circuit automatically adjusts the frequency of the applied panel signals to shift this frequency away from fixed frequency interference spectra, such as due to cathode-ray tube flyback signals, in the environment in which the touch panel is used. The touch location thereby minimizes the effects of such spectra on touch location determinations.
    Type: Grant
    Filed: August 26, 1986
    Date of Patent: October 6, 1987
    Assignee: Tektronix, Inc.
    Inventors: Robert D. Meadows, Philip T. Krein, Bruce Murdock
  • Patent number: 4698460
    Abstract: A touch panel has panel scanning signals selectively applied to the four sides of a touch sensing surface of the panel so as to establish alternating current voltage gradients in desired directions across the touch sensing surface. When the panel is touched, touch signals or currents result and are utilized by a touch location circuit in determining the location of touch. The impedance touch current resulting from a user's touch may also be determined and used. The touch panel circuit automatically compensates for changes in impedance touch current, such as result when users touch the panel with ungloved and gloved fingers. An analog multiplier is included in the touch location circuit to improve noise rejection. Auto nulling and automatic frequency adjustment is included in the touch panel device, together with overcurrent protection circuitry.
    Type: Grant
    Filed: August 26, 1986
    Date of Patent: October 6, 1987
    Assignee: Tektronix, Inc.
    Inventors: Philip T. Krein, Robert D. Meadows, Bruce Murdock, Daniel G. Teichmer