Patents Represented by Attorney Robert S. Hulse
  • Patent number: 4560998
    Abstract: The invention consists of a transformer coupled low voltage power amplifiers which provides the moderate voltage (200-500 V.sub.p-p) excitation potentials required by PZT ink jet or similar device elements. Transformer coupling is viable in that ink jet drive requirements are "return to zero" (no net DC component). Product safety aspects are enhanced since high voltage power supplies are not required, furthermore significant reductions in cost of implementation are realized due to the absence of high voltage power supplies and by allowing the use of monolithic power amplifiers. Savings in power may also be realized by matching the transformer to the ink jet PZT element as components of a resonant network.
    Type: Grant
    Filed: July 18, 1984
    Date of Patent: December 24, 1985
    Assignee: Tektronix, Inc.
    Inventor: Guenther W. Wimmer
  • Patent number: 4554536
    Abstract: Apparatus for displaying a logic timing diagram on a raster scan type display device is disclosed. A logic signal is sampled and representations thereof stored in a RAM. The RAM contents are read repeatedly in synchronism with a raster scan operation, and the read-out signal is delayed by a predetermined time which is shorter than one bit cycle of the read-out signal. Logical gating functions, OR, exclusive-OR and NAND gates, receive the delayed and undelayed signals, and provide output signals from which the display of the "High" level, edges and "Low" level of the logic timing diagram are derived. Since it is not necessary to convert the logic signal to display codes and rewrite a display RAM, high speed scrolling and magnification can be obtained quickly and easily.
    Type: Grant
    Filed: March 23, 1983
    Date of Patent: November 19, 1985
    Assignee: Tektronix, Inc.
    Inventor: Ronald M. Jackson
  • Patent number: 4551732
    Abstract: In a line scan graphic recording apparatus, the beam which displays the data on the recording media must be synchronized with the movement of recording media as it is directed normal to the displaying apparatus. The rate at which the recording media moves in its path is determined by the paper drive means. The rate is often non-uniform due to instantanteous velocity variations of the drive means. A drive velocity sensor produces a timing signal which controls the recording time of the input data image, stored digitally in a buffer memory device, by triggering the buffering device at the appropriate time and causing the image data to be transferred to the display for recording on the selected media.
    Type: Grant
    Filed: June 20, 1983
    Date of Patent: November 5, 1985
    Assignee: Tektronix, Inc.
    Inventor: Jerrold J. Rogers
  • Patent number: 4541100
    Abstract: An input apparatus for a multi-channel device, such as a logic analyzer, is disclosed, the input apparatus providing the multi-channel device with a programmable set-up and hold feature. The multi-channel device acquires a logic signal from a product under test, the logic signal having associated therewith an actual set-up and hold time with respect to an external clock signal. The actual set-up and hold times are entered into the multi-channel device via a keyboard and a display. The device has stored therein a desired set-up and hold time required by the logic signal relative to the external clock signal. In accordance with the actual and the desired set-up and hold times, the multi-channel device changes the relative orientation of the acquired logic signal with respect to the external clock signal, along the time axis until the set-up and hold times of the acquired logic signal are changed from the actual value to the desired value.
    Type: Grant
    Filed: July 19, 1982
    Date of Patent: September 10, 1985
    Assignee: Tektronix, Inc.
    Inventors: Steven R. Sutton, Michael S. Hagen, David D. Chapman, Glenn S. Gombert, Steven R. Palmquist
  • Patent number: 4540997
    Abstract: This invention includes a method and apparatus for causing ink to be ejected from the ink nozzles for a second selected time period if the printer has not functioned for a first selected time period independent of whether power is or is not applied to the printer during those periods. The first time period is selected to minimize the possibility of ink clogging the ink nozzles and the second time period is selected to dislodge any thickened ink which may have developed in the ink nozzle during the first time period. The first time period for most ink compositions and nozzle sizes will be considerably longer than the second time period.
    Type: Grant
    Filed: March 26, 1984
    Date of Patent: September 10, 1985
    Assignee: Tektronix, Inc.
    Inventors: Lawrence G. Biggs, Pierre Radochonski
  • Patent number: 4533861
    Abstract: The present invention relates to a drive circuit for a stepping motor. The drive circuit provides a low voltage to the coils of the stepping motor in the steady state, and a high voltage to the coils when changing state. As a result, the state changes rapidly and the stepping motor is driven efficiently. The high voltage is derived from the energy which was stored in the winding of the stepping motor before the switching occurred by transferring that energy to a capacitor which achieves a charge potential that is greater than the potential of the power supply voltage.
    Type: Grant
    Filed: October 13, 1983
    Date of Patent: August 6, 1985
    Assignee: Tektronix, Inc.
    Inventors: Jerrold J. Rogers, Joseph S. Trumps
  • Patent number: 4532605
    Abstract: The present invention relates to a capability present within a graphics display terminal wherein a zoom operation may be accomplished, the width of each of the lines of the zoomed image being maintained at a one pixel width regardless of the degree or amount of magnification of the zoomed image. This is accomplished by utilizing the firmware stored in the processor to perform the magnification of the image therein, prior to the storage of the appropriate binary data in the video display memory, the binary data being the pixel representation of the displayed image. Since the magnification of the image takes place prior to storage of the binary data in the video display memory, the graphics display terminal of the present invention can use this binary data to display an image, a zoomed image, the width of each line being equal to, approximately, a one pixel width. Therefore, despite the degree of magnification of the zoomed image, a very discernable, clear image will be displayed on the CRT.
    Type: Grant
    Filed: April 12, 1982
    Date of Patent: July 30, 1985
    Assignee: Tektronix, Inc.
    Inventor: William G. Waller
  • Patent number: 4529928
    Abstract: A circuit is described for automatically controlling an input current to a current translating device having an output current functionally related to the input current. A sensing circuit detects the output current of the device and produces a control signal representative of the output current. The control signal is coupled to a control circuit that varies the input current to the device. In the preferred embodiment of the invention, the dynamic range of the sensing circuit is increased by coupling a constant current generator to its input.
    Type: Grant
    Filed: May 20, 1983
    Date of Patent: July 16, 1985
    Assignee: Tektronix, Inc.
    Inventors: Jerrold J. Rogers, Judd L. Sirotiak
  • Patent number: 4528591
    Abstract: A scheme for digitizing a stationary video image is disclosed. The amplitude of a video signal, representing said video image, is sampled at a plurality of points along the time axis and is compared with the count in a counter. If the amplitude equals the count at a particular point on the time axis, the count is stored in a memory in a location corresponding to said particular point. The process is repeated until a count in the counter is stored in said memory in locations corresponding to all of said plurality of points along the time axis of said video signal. If two or more counters are used, each counting from a different initial value, and if two or more corresponding comparators are used to make the above comparison, the time required to digitize said stationary video image may be reduced. Consequently, the time required for the video image to remain stationary is reduced.
    Type: Grant
    Filed: August 16, 1982
    Date of Patent: July 9, 1985
    Assignee: Tektronix, Inc.
    Inventors: Steven F. Liepe, Pierre Radochonski, Glenn R. Johnson
  • Patent number: 4528642
    Abstract: A method and apparatus is disclosed for independently displaying one of a plurality of images on a display and for superimposing the plurality of images onto one another to produce a composite image. One or more bit planes are selected to constitute a group (defined to be a "surface"), and one or more additional bit planes are selected to constitute another group. The number of groups corresponds to the number of images to be independently displayed. The priority of one group over the other is selected. This ensures that the image from the one group (surface) appears to be "in front of" the images from the other group (surface) on the display. In the case of a color terminal, the colors associated with each group are selected. A color map memory contains a plurality of brightness indices which determines image brightness. Associated with each index is one or more color indices.
    Type: Grant
    Filed: April 12, 1982
    Date of Patent: July 9, 1985
    Assignee: Tektronix, Inc.
    Inventor: William G. Waller
  • Patent number: 4511235
    Abstract: A paper loading mechanism for a copier or the like is disclosed. A paper guide member and a foam pressure roller rotatably coupled to a paper drive roller feeds a web of paper to the drive roller, thereby semi-automatically feeding the paper along a predetermined path. A paper canister, having the webs of paper disposed therein, is affixed to a front cover of said paper loading mechanism. This structural arrangement simplifies the procedure of loading paper into the paper loading mechanism of the present invention.
    Type: Grant
    Filed: December 6, 1982
    Date of Patent: April 16, 1985
    Assignee: Tektronix, Inc.
    Inventor: Thomas J. Koller
  • Patent number: 4507576
    Abstract: A special purpose pulse amplifier with programmable high and low levels for complex IC testing is disclosed. Its output has independently programmable positive and negative transition rates and is reverse terminated in 50 ohms. It also has the ability to be switched to a high resistance, low capacitance output state. This circuit is the interface between a complex, computer controlled system of timing and pattern generation hardware, and an integrated circuit to be tested. This device has reduced waveform aberrations, lower inhibited capacitance, low input to output delay for reducing timing error, programmable signal transition rates, and the amplitude range and transition rate control to accommodate all the important device technologies expected in high pin-count parts.
    Type: Grant
    Filed: October 28, 1982
    Date of Patent: March 26, 1985
    Assignee: Tektronix, Inc.
    Inventors: David R. McCracken, Robin R. Larson
  • Patent number: 4499501
    Abstract: An image quality enhancement scheme is disclosed wherein the image information associated with each line of an image source is transferred to one line of an image receiving medium a plurality of times, the quality of the image information transferred to one line of the image receiving medium gradually improving following each subsequent transfer. A fiber optic cathode ray tube (CRT) transfers the image information to the image receiving medium. An electron beam generator in the CRT traces a plurality of scan lines on the inner faceplate of the CRT. The image receiving medium scrolls across the face of the CRT in synchronism with the trace of each of the scan lines on the inner faceplate thereof. The image information associated with each line of the image source is transferred to the one line of the image receiving medium via the trace of each of the plurality of scan lines.
    Type: Grant
    Filed: September 1, 1982
    Date of Patent: February 12, 1985
    Assignee: Tektronix, Inc.
    Inventors: Joern B. Eriksen, Pierre Radochonski
  • Patent number: 4493044
    Abstract: A method and apparatus for establishing the correct order of probe channels in a logic analyzer is disclosed. Logic analyzers have probe PODS connected thereto, the PODS having a plurality of probe tips connected thereto for further connection to the terminals of a product under test. With this invention, the order of connection of the tips to the terminals can be ignored because the correct order is established via the logic analyzer (LA) itself. A ROM has firmware stored therein for enabling the logic analyzer to establish the correct order of connection. The binary data from each POD is stored in memory. The binary data in memory may be converted to hexadecimal form and stored in the display controller. By using a keyboard, the operator displays, on the LA display, a menu-mode display, which includes a display of the probe channel identifiers for each POD, the identifiers reflecting the actual order of connection of the probe tips to the terminals of the product under test.
    Type: Grant
    Filed: March 8, 1982
    Date of Patent: January 8, 1985
    Assignee: Tektronix
    Inventors: Hoeren Gerd H., Steven R. Palmquist
  • Patent number: 4367518
    Abstract: In an apparatus capable of duplicating jacketed and unjacketed microfiche, a bank of clear cylindrical lenses is provided, each lens being divided into segments by a series of substantially opaque baffles. The lenses are used with a corresponding bank of aperture lamps, and are disposed between the lamps and microfiche to provide relatively uniform, collimated light upon an image plane, the side of the lenses closest to the microfiche being flattened, and the baffles having an index of refraction lower than that of the clear segments of the lens.
    Type: Grant
    Filed: April 6, 1978
    Date of Patent: January 4, 1983
    Assignee: AM International, Inc.
    Inventor: William E. Roberts
  • Patent number: 4287564
    Abstract: A method of reading selected ones of an array of data frames from a microfiche medium substantially without errors attributable to misalignment of the frames. The method, which utilizes a microfiche reader-printer in adjusting for misalignment of the frames, includes the steps of determining the average distance between the frames along a first selected axis (e.g., the X-axis) of the array, and using said average distance in positioning the frames along the axis for reading. The frames are separated from each other by a predetermined nominal distance along the axis. The average distance is determined by dividing the distance between the outermost frames along the axis (the distance between the outermost frames being expressed in terms of the number of stepper motor steps needed to traverse said distance) by one less than the number of frames along said axis to produce a quotient, and adding the quotient to the predetermined nominal distance.
    Type: Grant
    Filed: April 2, 1979
    Date of Patent: September 1, 1981
    Assignee: AM International, Inc.
    Inventors: William R. Swift, Don W. Herrod, James M. Marsh
  • Patent number: 4283136
    Abstract: The microfiche reader printer has multiple format capabilities. A lens support holding one lens for each format is slidable to position a lens into the light path. Positioning of the lens support closes or opens switches which direct a logic circuit to cause a controller to drive the microfiche holding platen in a certain manner dependent on the format. Copying utilizes a rotating xerographic drum. The platen is driven by stepper motors having a digitized sinusoidal input for microstepping drive for constant velocity drive during copying where the movements of the platen and the drum must be coordinated. The platen also takes a half frame back step before printing so that it can accelerate forward over the half step forward to reach constant velocity during scanning of the frame.
    Type: Grant
    Filed: September 5, 1978
    Date of Patent: August 11, 1981
    Assignee: AM International, Inc.
    Inventors: William R. Swift, Don W. Herrod, James M. Marsh
  • Patent number: 4265196
    Abstract: Apparatus for applying toner to a tape which has toner-attracting images thereon, including a chamber containing toner, a chamber inlet located below the top of the toner, a chamber outlet above the top of the toner, and a tape guide which is convex along the tape path which leads through the toner to minimize toner pickup on the rear face of the tape. A vacuum is maintained at the top of the chamber to create an inflow of air at the tape outlet, to sweep back loose toner.
    Type: Grant
    Filed: June 19, 1978
    Date of Patent: May 5, 1981
    Assignee: AM International, Inc.
    Inventors: Alfred M. Nelson, David L. Davis
  • Patent number: 4256036
    Abstract: A printing machine is provided for imprinting forms with fixed data from embossed printing plates and variable data from manually settable print wheels by moving a roller platen from a start position across the printing elements and the form to an actuated position to perform a printing operation and back to the start position to complete a printing cycle. The print wheels are selectively positionable by keyset levers movable from a zero position to a selected printing position for rotating each of the print wheels to a desired peripheral setting. Reset means is provided for restoring each of the keyset levers from the selected printing position to the zero position in response to movement of the roller platen through a printing operation, and lock-out means is provided to inhibit movement of the roller platen through a printing operation following a printing cycle. The roller platen is unlocked for movement in response to movement of at least one of the keyset levers from the zero position to a new setting.
    Type: Grant
    Filed: September 10, 1979
    Date of Patent: March 17, 1981
    Assignee: AM International, Inc.
    Inventors: Lewis E. Sauerwein, Richard L. Gross
  • Patent number: 4254371
    Abstract: A series of velocity curves are generated empirically to create a library of information from which a pulse rate for a stepper motor may thereafter be called upon to drive a load a given distance in the minimum time without rebound, known as ringing.
    Type: Grant
    Filed: August 28, 1978
    Date of Patent: March 3, 1981
    Assignee: AM International, Inc.
    Inventor: Frank L. Scholten