Cathode-ray Tube Patents (Class 324/404)
  • Patent number: 11751316
    Abstract: A power transfer and monitoring device for an X-ray tube may include: an X-ray filament; a transformer including a primary coil and a secondary coil, wherein the secondary coil of the transformer includes a first leg, a second leg, and a middle leg; a current supply configured to supply a sinusoidal current to the primary coil of the transformer; and a calculation unit configured to measure a primary current of the transformer, configured to determine a synthesized transformer magnetizing current, and configured to subtract the synthesized transformer magnetizing current from the primary current of the transformer to determine a value of filament current through the X-ray filament. The first and second legs of the secondary coil of the transformer alternately supply current to a first end of the X-ray filament. The middle leg of the secondary coil of the transformer supplies current to a second end of the X-ray filament.
    Type: Grant
    Filed: November 5, 2019
    Date of Patent: September 5, 2023
    Assignee: GULMAY LIMITED
    Inventors: Stuart Duncan, Tony Durrant
  • Patent number: 11176859
    Abstract: A method comprises acquiring measured luminance levels at a measurement point of a display area for a plurality of test images displayed in the display area, and estimating one or more luminance levels at one or more corresponding luminance estimation points of the display area using the measured luminance levels. The method further comprises determining, based on the one or more estimated luminance levels, a correction parameter using the estimated one or more luminance levels.
    Type: Grant
    Filed: March 24, 2020
    Date of Patent: November 16, 2021
    Assignee: Synaptics Incorporated
    Inventors: Masao Orio, Joseph Kurth Reynolds, Xi Chu, Takashi Nose, Hirobumi Furihata
  • Patent number: 8332175
    Abstract: An oscilloscope probe calibrating system for a single terminal probe and a differential probe includes an oscilloscope, a main branch module, a sub-branch module, and a resistor. The oscilloscope includes multiple inputs for receiving signals from the single terminal probe and the differential probe, an output for outputting an original calibration signal, and a display module displaying the waveforms of the original calibration signal and the signals from the single terminal probe and the differential probe. The main branch module converts the original calibration signals to a number of first calibration signals. The sub-branch module converts the first calibration signals to a number of second calibration signals. The sub-branch module includes a single terminal sub-branch module and a differential sub-branch module coupled to the main branch module. One end of the resistor is connected between the main branch module and the differential sub-branch module, and the other end is grounded.
    Type: Grant
    Filed: August 16, 2010
    Date of Patent: December 11, 2012
    Assignees: Hong Fu Jin Precision Industry (ShenZhen) Co., Ltd., Hon Hai Precision Industry Co., Ltd.
    Inventor: Hui Li
  • Patent number: 8179138
    Abstract: A cathode ray tube (CRT) test system for testing a CRT device is disclosed. The CRT test system comprises a connecting device, a power module, a control module, a first test module, and an illumination module. The connecting device detachably and electrically connects with the CRT device; the power module electrically connects with the connecting device; the control module electrically connects with the connecting device; and the control module comprises test program. After the CRT device receives a control signal transmitted from the test program, the CRT device generates a response signal and transmits the response signal to the first test module. When the first test module detects that the control signal and the response signal fit in with a first test signal status, the illumination module displays a first light sign; when the control signal and the response signal do not fit in with the first test signal status, the illumination module displays a second light sign.
    Type: Grant
    Filed: November 20, 2009
    Date of Patent: May 15, 2012
    Assignee: Wistron Corporation
    Inventors: Hsiang Chang, Cheng-Hsuan Tsai, Ming-Chang Liu
  • Patent number: 8159238
    Abstract: Some embodiments of the present invention describe an apparatus that includes an oscillator, a ramp generator, and an inverter. The apparatus includes an oscillator, an inverter, and a ramp generator. The oscillator is configured to generate a waveform comprising a low time and a high time. The inverter is configured to receive the waveform generated by the oscillator, and invert the waveform. The ramp generator configured to increase a gate control voltage of a transistor connected to a solar cell, and rapidly decrease the gate control voltage of the transistor. During the low time of the waveform, a measurement of a current and a voltage of the solar cell is performed as the current and voltage of the solar cell are transmitted through a first channel and to a second channel.
    Type: Grant
    Filed: September 30, 2009
    Date of Patent: April 17, 2012
    Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space Administration
    Inventors: Michael J. Krasowski, Norman F. Prokop
  • Patent number: 7427887
    Abstract: An open drain driver (7) selectively switches a MOSFET switch (MN1) which is passively held in the conducting state into the non-conducting state. The MOSFET switch (MN1) switches an AC analogue input signal on a main input terminal (3) to a main output terminal (4) and the gate of the MOSFET switch (MN1) is AC coupled by a capacitor (C1) to the drain thereof. The open drain driver (7) comprises a first MOSFET (MN2) and a second MOSFET (MN3) through which the gate of the MOSFET switch (MN1) is pulled to ground (Vss). The gate of the first MOSFET (MN2) is coupled to the supply voltage (VDD) for maintaining the first MOSFET (MN2) in the open state. A control signal is applied to the gate of the second MOSFET (MN3) for selectively operating the open drain driver (7) in the conducting state for operating the MOSFET switch (MN1) in the non-conducting state.
    Type: Grant
    Filed: May 13, 2005
    Date of Patent: September 23, 2008
    Assignee: Analog Devices, Inc.
    Inventors: John J. O'Donnell, Michael Christian Wohnsen Coln, Maria del Mar Chamarro Marti
  • Patent number: 6661629
    Abstract: An insulating member is used on or with a high-voltage probe that applies a voltage to the anode of a cathode ray tube during manufacture of the tube. If there are flaws in the frit seal of the tube, the probe produces arcing through the flaw into a grounded, conductive band disposed around the exterior of the frit seal. The insulating member is placed between the high-voltage probe tip and the grounded band around the frit seal. Consequently, the insulating member prevents electrical arcing external to the cathode ray tube between the high-voltage probe and the grounded band. Such arcing would otherwise interfere with the testing of the frit seal and could possibly damage the test equipment.
    Type: Grant
    Filed: April 20, 2001
    Date of Patent: December 9, 2003
    Assignees: Sony Corporation, Sony Electronics, Inc.
    Inventors: David Allen Murtishaw, Brian Michael Solomich, Edward Martinez
  • Patent number: 6577132
    Abstract: A passive device for the detection and indication of non-ionizing electromagnetic radiations and static electricity is provided. The device is especially designed to be applied to or integrated in an anti-radiation/anti-static/anti-reflection filter intended to block the aforementioned emissions, particularly in devices with cathode ray tubes(CRT).
    Type: Grant
    Filed: November 12, 2001
    Date of Patent: June 10, 2003
    Inventor: Jorge Raul Bartulos
  • Patent number: 6559591
    Abstract: A non-adhesive, conductive strip is used to provide an electrical ground path between a solder electrode on the anti-reflective film of a cathode ray tube and the reinforcement or heat shrinkage band on the tube. The conductive strip is preferably held in place on the cathode ray tube using a magnet or magnets. Consequently, because the conductive strip is held in place by magnets and is non-adhesive, it can be removed and replaced repeatedly during the testing of the solder electrodes and anti-reflective film without potentially damaging the solder electrode or degrading the performance of the conductive tape that is typically used as the ground path in a completed cathode ray tube.
    Type: Grant
    Filed: June 5, 2001
    Date of Patent: May 6, 2003
    Assignees: Sony Corporation, Sony Electronics, Inc.
    Inventor: David Allen Murtishaw
  • Patent number: 6483313
    Abstract: An apparatus and method are provided for measuring convergence of the Red-Green-Blue (R.G.B.) signals of a color cathode ray tube (CRT) using a color charge coupled device (CCD) camera. A uniform R.G.B. brightness value is picked up by the color CCD camera at all positions of the CRT screen when the color CCD camera images the screen, thus enabling convergence to be more accurately measured and adjusted. Test patterns having a constant R.G.B. brightness value are displayed on the screen of the CRT by a pattern generator. The displayed test patterns are picked up by the color CCD camera, and when the R.G.B. brightness values differ from a corresponding reference brightness value, a controller adjusts the intensity of each of the R.G.B. signals of each test pattern by suitably controlling the pattern generator. A uniform R.G.B. brightness value is thus provided for all test patterns displayed on the CRT screen. Only after the R.G.B.
    Type: Grant
    Filed: August 1, 2000
    Date of Patent: November 19, 2002
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Wan-Soo Kim, Chang-Gun Lee
  • Patent number: 6456080
    Abstract: A cathode ray tube including a bulb having a screen on which a fluorescent film is formed, and a funnel portion having a neck portion on the side opposite to the screen, an electron gun mounted in the neck portion of the bulb, a deflection yoke mounted on the bulb, for deflecting an electron beam emitted from an electron gun, a velocity modulator installed around the neck portion, and an eddy current generation preventing means installed on an electrode of the electrode gun, which corresponds to the velocity modulator, for preventing generation of an eddy current by the velocity modulator. Here, the electron gun has a cathode forming a triode portion, a control electrode, a screen electrode, a plurality of focusing electrodes sequentially aligned from the screen electrode, and a final accelerating electrode which is installed adjacent to a focusing electrode the farthest away from the cathode or protects a predetermined width of the outer circumferential surface of the focusing electrode.
    Type: Grant
    Filed: August 22, 2000
    Date of Patent: September 24, 2002
    Assignee: Samsung SDI Co., Ltd.
    Inventors: Sang-kyun Kim, Sang-mook Kim, Duk-sung Park, Bong-wook Jung
  • Patent number: 6211629
    Abstract: The cut-off level (Vcod) of a drive signal (Vd) of a cathode ray tube (3) is (Ib1, Ib2) occurring at these two levels (Vd1, Vd2).
    Type: Grant
    Filed: March 2, 2000
    Date of Patent: April 3, 2001
    Assignee: U.S. Philips Corporation
    Inventors: Dirk J. A. Teuling, John H. P. Moors
  • Patent number: 6104194
    Abstract: In a method for determining whether electronic charge has been accumulated on the inner surface of a cathode ray tube (10), at least one electron beam is generated within the cathode ray tube and is deflected so that it hits the inner surface of the funnel (14) of the cathode ray tube. The temperature of a portion of the cathode ray tube is measured and is compared with a reference temperature value. If the measured temperature is greater than or equal to the reference temperature, it is determined that the electronic charge has accumulated. If the measured temperature is below the reference temperature, then the electron beam or beams have become switched off and electronic charge may not have accumulated on the inner surface of the cathode ray tube.
    Type: Grant
    Filed: February 6, 1998
    Date of Patent: August 15, 2000
    Assignees: Sony Corporation, Sony United Kingdom Limited
    Inventor: Hideo Kato
  • Patent number: 5994841
    Abstract: A circuit apparatus and method is disclosed for determining the actual beam current of a display device having at least one cathode and that actual beam current is used to both correctly bias a voltage that drives the display device and determine the actual drive voltage according to a desired beam current. At periodic intervals, according to the invention, a series of test voltages in known relation to one another are applied to the display device, and measured cathode currents corresponding to the applied voltages are stored in appropriate memory elements of an correction unit. If at least two of the test voltages is selected to result in a black level, and at least one of the test voltages is selected to result in a white level beam current then the correction unit can precisely determine actual beam current through application of a mathematical relationship between test voltage an measured beam current which takes into account a leakage current between a cathode and a first grid of the display device.
    Type: Grant
    Filed: October 17, 1997
    Date of Patent: November 30, 1999
    Assignee: Welch Allyn, Inc.
    Inventors: Michael W. Allen, Paul DeLucia
  • Patent number: 5929641
    Abstract: A cathode ray tube may utilize a focus mask color-selection structure. The focus mask structure is susceptible to localized, transient short circuit events, or breakdown events. These events may be caused by conductive particulates that become free within the cathode ray tube and provide a short circuit between first and second layers of the focus mask. The breakdown events are undesirable because they may result in cross-strand currents causing mask strand magnetization that can interfere with a video image on the screen of the cathode ray tube. A transformer rapidly senses random changes in a voltage or a current supplied to the second layer of the focus mask. A pulse waveform generator is coupled to the transformer and provides a pulse waveform responsive to the sudden change in voltage or current.
    Type: Grant
    Filed: August 22, 1996
    Date of Patent: July 27, 1999
    Assignee: Thomson Consumer Electronics, Inc.
    Inventors: Paul Kuczer, Richard William Nosker
  • Patent number: 5561578
    Abstract: The invention tests the operation of a CRT X-ray protector circuit without applying an abnormally high voltage to the CRT. In addition to a first reference voltage corresponding to the detected voltage which is the standard for the operation of the X-ray protector for use in a display device with the CRT, a second reference voltage set at a value lower than the first reference voltage and higher than 0 V is provided to enable the operation of the X-ray protector circuit by comparing the detected voltage with the second reference voltage at the time of testing the X-ray protector circuit's operation. A third reference voltage, higher than the first reference voltage, is compared to the detected voltage during channel switching or external input switching to prevent erroneous activation of the x-ray protector.
    Type: Grant
    Filed: May 3, 1994
    Date of Patent: October 1, 1996
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Susumu Shimoyanagida
  • Patent number: 5231489
    Abstract: A Moire measurement system uses spectral analysis to characterize the moire effect on a television signal introduced by a particular device. A known television signal is processed by the particular device, such as a video tape recorder, and the output is input to a spectral analyzer, such a windowed fast Fourier transform. The spectral analyzer includes input gating to select a portion of the known television signal from the particular device. The frequency of the desired component of the known television signal, together with the rms values of all the other components introduced by the Moire effect, give the X- and Y-coordinates of a point on an output display. The window is moved across the test signal, giving a family of X- and Y-coordinates that characterize the Moire effect as a function of amplitude, frequency or video pedestal. The Moire characteristics of the particular device then may be used to correct the output of the particular device.
    Type: Grant
    Filed: May 6, 1992
    Date of Patent: July 27, 1993
    Assignee: Tektronix, Inc.
    Inventor: Bruce J. Penney
  • Patent number: 5115229
    Abstract: A system and method for the accurate reproduction of the tone and luminance of a first video monitor screen includes, in one embodiment, a first video monitor and a second video monitor, each with a CRT screen. A gray scale test pattern is shown on both screens. The test pattern on each screen is measured using a spot photometer and the results are entered into a computer memory look-up table and compared, a tone-by-tone basis. A set of corrections is obtained for each tone of the gray scale. Those compensating corrections are used to adjust the luminance, on a pixel-by-pixel basis, of the second video screen of the second video monitor, so that the second screen is compensated to produce a gray scale which reproduces the tone and luminance values of the gray scale on the first screen.
    Type: Grant
    Filed: June 26, 1990
    Date of Patent: May 19, 1992
    Inventor: Hanoch Shalit
  • Patent number: 5077600
    Abstract: A convergence measurement apparatus for a color CRT comprising a light sensor which is placed on the face of a CRT to be tested, a CPU, and a pattern generator which causes a plurality of luminescent lines of a primary color to be displayed on one area of the CRT screen and a plane area comprised of a composite of the two other primary colors to be displayed on another area of the screen. The plurality of lines are shifted at a given rate along the designated area of the screen, the color of the displayed lines successively changing to show each primary color. The light sensor receives light intensity information from the generated pattern and the CPU calculates a mis-convergence value based on the light intensity data. The apparatus further includes a self-inspection feature by which the processing is executed for successive measurement of the same primary color.
    Type: Grant
    Filed: October 1, 1990
    Date of Patent: December 31, 1991
    Assignee: Sony Corporation
    Inventors: Hiroshi Ichigaya, Satoshi Sato
  • Patent number: 4989072
    Abstract: An adjusting apparatus for cathode ray tube equipment for convergence and/or image distortion adjustment which includes a pattern generator connected to a cathode ray tube to be measured and which generates a predetermined pattern having a plurality of bars and a white area, a probe attached to a front face of the cathode ray tube to be measured, and which includes a photo detector and a switch for starting measurement, an analog-to-digital converter connected to the probe, a measured data memory connected to an analog-to-digital converter for storing data received by the probe, a processor for controlling the pattern generator, receiving data from the measured data memory, and calculating the data according to various measurement routines.
    Type: Grant
    Filed: January 29, 1990
    Date of Patent: January 29, 1991
    Assignee: Sony Corporation
    Inventors: Satoshi Sato, Hiroshi Ichigaya
  • Patent number: 4988857
    Abstract: This invention is concerned with apparatus for automatically measuring misconvergence in the production of color Braun tubes or color display apparatus using color Braun tubes.
    Type: Grant
    Filed: May 4, 1989
    Date of Patent: January 29, 1991
    Assignee: Hitachi, Ltd.
    Inventors: Takumi Karasawa, Michio Tsukii, Takashi Atobe, Takaaki Ishikawa, Kazuhiko Mizuno
  • Patent number: 4963828
    Abstract: For the purpose of automated evaluation of white uniformity, the apparatus comprises a color television camera for picking up an image of white color displayed on the color cathode-ray tube, a circuit for separating color signals from the output signal of the color television camera, A/D converters for converting the analog color signals into digital color signals, memories for storing the digital color signals, and a computer for analyzing the contents of the memories. A nonuniform color portion is extracted from the color distribution of the display on the cathode-ray tube, and quantities of various features of the nonuniform color portion, for example, the hue, saturation and area of the nonuniform color portion and the degree of change in the saturation at the marginal edge contour of the nonuniform color portion are calculated by the computer to provide parameters used for evaluation of the white uniformity.
    Type: Grant
    Filed: February 13, 1989
    Date of Patent: October 16, 1990
    Assignee: Hitachi, Ltd.
    Inventors: Keisuke Kawame, Toshio Asano, Jun Mochizuki
  • Patent number: 4893925
    Abstract: Prior art instruments for testing a display unit suffer from the disadvantage that a testing system has to be customized for each type of display unit. The present invention optical measurement system, by utilizing an optical sensor, a three-dimensional transport system and a focus lens, provides for a universal system which is adaptable to test all kinds of display units. To provide for mobility and compactness, the optical sensor, the transport mechanism, the focus lens, in addition to the electronic circuit cards for controlling the motions thereof, are all mounted within a movable cart. To ensure that all kinds of display units may be tested on the same cart, a pivotable mirror assembly is mounted to the cart, with its line of sight axis aligned, closely to the screen of any to be tested display unit, such that the output from the display unit is reflected onto the focus lens and subsequently measured by the optical sensor.
    Type: Grant
    Filed: May 26, 1988
    Date of Patent: January 16, 1990
    Assignee: Grumman Aerospace Corporation
    Inventors: Kevin T. Sweeney, Joseph P. Mattal, Mitchell L. Kushner, Robert H. Lemke
  • Patent number: 4814858
    Abstract: Disclosed are a method of measuring the color purity of a color display having phosphors in the shape of dots and an apparatus therefor which are capable of quantitatively measuring the state of the phosphors being irradiated with electron beams with high accuracy. Magnetic field is applied to the color display tube from the outside so as to forcibly move an electron beam deflectively along a straight line and a photograph of the phosphor in this state is taken so as to obtain the configuration (the center position, and the radius or the diameter) of the phosphor from the image of the phosphor. After the two center positions of the electron beams in the positive and negative directions of the external magnetic field are then obtained, the center position of the electron beam under no excitation is obtained as the interior division point.
    Type: Grant
    Filed: April 6, 1988
    Date of Patent: March 21, 1989
    Assignee: Hitachi, Ltd.
    Inventors: Jun Mochizuki, Toshio Asanoh
  • Patent number: 4797619
    Abstract: An apparatus and method for measuring the spatial characteristics of color CRTs includes the scanning of an image of a white vertical line with a knife edge aperture and integrating the intensity values at each position of the knife edge. The centroids of the beams of the CRT are found by determining the X coordinants of the 50% points of the Y axis of the integral data, and the spatial line profiles are determined by differentiating the integral data. The integral data may be fitted to a Gaussian curve prior to analysis.
    Type: Grant
    Filed: March 13, 1987
    Date of Patent: January 10, 1989
    Assignee: EG&G Gamma Scientific Incorporated
    Inventors: Richard L. Austin, Herbert J. Otto, Frank L. Jones
  • Patent number: 4768091
    Abstract: Testing apparatus in accordance with the invention generates a composite video signal for a CRT which produces a scanning line raster on the video screen thereof clearly displaying the spot size and line focus of the scanning electron beam generating such raster. The display consists of a single scanning test line of high luminance, or white, within an intermediate low luminance or black portion of an otherwise white scanning line raster. The test line is segmented, with black gaps at several discrete locations thereon, each gap being approximately three times the width of the scanning beam spot. Centered within each such gap is a region of high luminance, or white, of a width approximately that of the beam spot. The line focus and spot size of the smallest possible picture element is thereby accurately displayed and so can be measured on the video screen, enabling adjustment of the focussing components for optimum focus.
    Type: Grant
    Filed: October 19, 1987
    Date of Patent: August 30, 1988
    Assignee: North American Philips Corp.
    Inventors: Robert E. Pooler, William R. Kaylor
  • Patent number: 4763004
    Abstract: A method of correcting the aberration of an electron beam due to astigmatism and field curvature of focus by feeding a correction current through stigmator coils and a focus correction coil. The correction currents are determined by measuring a sharpness P of the electron beam. The sharpness P is defined as a product of p.sub.x, a sharpness measured when the electron beam is deflected in X direction, and p.sub.y, a sharpness measured when the electron beam is deflected in Y direction: P=p.sub.x .times.p.sub.y. The use of the sharpness P provides good convergence of the measurements and it becomes possible to calibrate the electron beam for many points in the scanning field. Thus, it is possible to attain maximum resolution over an entire scanning field.
    Type: Grant
    Filed: January 4, 1985
    Date of Patent: August 9, 1988
    Assignee: Fujitsu Limited
    Inventors: Hiroshi Yasuda, Takayuki Miyazaki
  • Patent number: 4754329
    Abstract: A method of focusing and calibrating a display screen which is coupled to a video camera where the display screen is not visible when performing the calibration. The method includes the steps of generating a reference signal to display an image on the display screen, capturing an image of the display signal in the video camera and converting the image into digital signals representing the brightness of pixels in a pixel matrix, analyzing the digital signals for data representing predetermined physical parameters of the visual display on the screen, and generating on a separate display screen a graphic representation of these physical parameters. By observing the bar graphs on a microcomputer at the same time that adjustments are made to the focus, intensity, and rotation controls on the oscilloscope, the display screen may be focused and calibrated.
    Type: Grant
    Filed: April 13, 1987
    Date of Patent: June 28, 1988
    Assignee: Tektronix, Inc.
    Inventors: James W. Lindsay, Geoffrey B. Rhoads
  • Patent number: 4752825
    Abstract: The display simulator analyzer is a fully integrated processor controlled instrument used for testing video display devices. The test signals may be generated by a video function generator, a high resolution graphics generator, a modulator or combinations thereof. As the name implies, the simulator-analyzer also measures and analyzes parameters generated from an euipment under test by means of its analyzer, which has incorporated therein a counter-timer, a real time digitizer and a sync stripper.
    Type: Grant
    Filed: October 10, 1986
    Date of Patent: June 21, 1988
    Assignee: Grumman Aerospace Corporation
    Inventors: Robert M. Buckley, Joseph Lovrecich, William R. Biagiotti
  • Patent number: 4720282
    Abstract: A method for holding a cathode-ray tube in a fixed position during processing utilizes mounting lugs attached to the tube. The apparatus includes a platform having a plurality of legs positioned to support, respectively, the ends of the mounting lugs. Each of the legs has a recess therein aligned with an aperture in the respective lug end. Each lug is secured to the respective leg by a clamp, pivotally attached to each leg, which projects through the aperture into the respective recess when pivoted.
    Type: Grant
    Filed: January 12, 1987
    Date of Patent: January 19, 1988
    Assignee: RCA Corporation
    Inventors: Thomas L. Chase, Kenneth A. Long
  • Patent number: 4709191
    Abstract: The present invention relates to a process and a device for adjusting a deflection unit without utilizing a test tube whereby a measuring head is employed that samples the field along the length of the axis of the deflection unit in at least two zones, and the signals issuing from the measuring head represent the fields generated by the line and raster windings. These signals are connected to a computer that simulates the mechanical adjusting operations such that the error signal supplied to a servo-device may control the displacement motors of the raster with respect to the center line of the deflection unit.
    Type: Grant
    Filed: September 16, 1985
    Date of Patent: November 24, 1987
    Assignee: Videocolor
    Inventors: Roger Pieri, Jean C. Fringant
  • Patent number: 4677340
    Abstract: The cathode-ray-tube beam deflection of an oscilloscope is automatically calibrated by photoelectrically detecting the intersection of the tube's electron beam with visible graticule lines on the tube's faceplate. An input signal is compared, at the time of intersection, with stored values representative of the graticule lines, and the deflection amplifier gain of the oscilloscope is adjusted until the graticule lines properly represent the measurement of the input signal.
    Type: Grant
    Filed: December 24, 1984
    Date of Patent: June 30, 1987
    Assignee: Tektronix, Inc.
    Inventors: Lawrence J. Miller, Donald P. Chitwood
  • Patent number: 4650436
    Abstract: An apparatus for centering a deflection yoke in a support ring includes a spindle having a tapered portion and a cylindrical portion. A spider, having radial arms, is centered on the spindle. A planar member includes an inset which is centered on the spindle, and is supported on the radial arms. The inset centers the support ring on the spindle. The tapered portion centers a yoke on the spindle whereby the yoke is centered in the support ring. Holding members are in the support ring, and hold the yoke centered in the support ring.
    Type: Grant
    Filed: October 30, 1985
    Date of Patent: March 17, 1987
    Assignee: RCA Corporation
    Inventors: Dennis E. Thro, Mort J. Nierenberg
  • Patent number: 4602272
    Abstract: A system for measuring the intensity profiles of the electron beams of color kinescopes includes a camera having a CCD. A color field is placed on the kinescope screen and a pixel in the center of one of the colored stripes is selected. The color field is turned off and the beam is scanned in short lines in one direction and incrementally stepped across the selected pixel in the perpendicular direction. The charge level on the selected pixel is representative of the beam intensity and is recorded. The entire beam is stepped across the pixel to measure the intensity profile in one direction. The directions of scanning and stepping are then interchanged to measure the beam intensity profile in the normal direction. The process is then repeated for the other electron beams in the kinescope.
    Type: Grant
    Filed: November 13, 1984
    Date of Patent: July 22, 1986
    Assignee: RCA Corporation
    Inventor: Robert A. Duschl
  • Patent number: 4568975
    Abstract: A method and apparatus for measuring the Gray Scale characteristics of a CRT display wherein a luminance meter surveys a ten percent portion of the total surface area of the screen of the CRT display screen. The luminance meter is positioned far enough from the screen so that the cone surveyed by the luminance meter will intersect the plane of the screen to cause ten percent of the screen surface area to be surveyed. A special test pattern is generated for display on the CRT screen whereby a surveyed area is provided having a sufficiently large surface area and being of uniform brightness. The test pattern also provides for an additional screen area equal in size to the surveyed area. The average picture level for the surveyed area and the non-surveyed area is maintained at fifty percent of peak picture level while the brightness of the surveyed area is varied in incremental steps through the Gray Scale.
    Type: Grant
    Filed: August 2, 1984
    Date of Patent: February 4, 1986
    Assignee: Visual Information Institute, Inc.
    Inventor: John H. Harshbarger
  • Patent number: 4563649
    Abstract: Tracking of the electron guns of a multiple-gun cathode ray tube system is tested by individually testing the emission current of each gun, storing voltages proportional to the emission currents of each gun and subsequently selecting the highest voltage stored and comparing it to each of the stored voltages.
    Type: Grant
    Filed: July 11, 1983
    Date of Patent: January 7, 1986
    Assignee: Sencore, Inc.
    Inventor: Barry A. Arenson
  • Patent number: 4536792
    Abstract: A method and apparatus for testing the geometry of a cathode ray tube raster scan under beam duty cycle variation. Alternate polarities of white on black and black on white images of a test pattern are displayed on the CRT screen, and the displacement of a reference point from one polarity to the other is measured to determine quantitatively the amount of displacement. Preferably, the pattern comprises a plurality of regularly arranged and spaced graphic elements, such as a bar, dot or dot grating pattern, wherein the pattern occupies a low percentage of the screen area. By alternately switching the polarity, the electron beam of the CRT undergoes wide swings in the amount of current it draws from the high voltage supply, and the amount of image displacement and size deviation can be readily measured.
    Type: Grant
    Filed: November 23, 1983
    Date of Patent: August 20, 1985
    Assignee: Visual Information Institute, Inc.
    Inventor: John H. Harshbarger
  • Patent number: 4459551
    Abstract: A television receiver and test set voltage analyzer includes a set of parallel connected switches which individually apply the various operating voltages to a readout device. The analyzer replaces a television picture tube so that the verification of the presence of all operating voltages indicates a failed tube while the absence of an operating voltage indicates a receiver or test set failure.
    Type: Grant
    Filed: September 28, 1981
    Date of Patent: July 10, 1984
    Assignee: RCA Corporation
    Inventor: Kenneth J. Yakmovitz
  • Patent number: 4445872
    Abstract: In a method of vaporizing getter material from a getter container inside a vacuum electron tube, light from the vaporization is sensed at least from the outset of the heating of the container. A time-dependent sample signal is produced from the sensed light which is compared with time-dependent criteria related to the vaporization, and a characteristic of the vaporization is derived from the comparison.
    Type: Grant
    Filed: January 18, 1982
    Date of Patent: May 1, 1984
    Assignee: RCA Corporation
    Inventor: James G. Ottos
  • Patent number: 4439735
    Abstract: A method and apparatus are described for testing a line screen CRT for misregistration between its electron beam and the beam's phosphor stripe targets. The test method includes sensing light output at a plurality of test areas on the CRT screen as the electron beam is stepped across its phosphor targets. The maximum and minimum light outputs of each test area, and the beam locations at which the maximum and minimum light outputs were obtained, are used to compute the degree of misregistration for each test area.
    Type: Grant
    Filed: July 17, 1981
    Date of Patent: March 27, 1984
    Assignee: Zenith Radio Corporation
    Inventors: Armando Alvite, Enrico D. Hines, Allan D. Kautz
  • Patent number: 4433292
    Abstract: A color tube so arranged as to check the operation of an electron gun reserved for a particular type of visual display such as a red warning signal and therefore not normally employed for independent operation. The arrangements contemplated preferably include direct checking for continuity of the corresponding filament circuit by means of a separate output lead from said filament, as well as checking of the emission of the reserved-gun cathode by inserting an additional anode which is intended to form a diode with said cathode. Testing by means of the additional external connections thus formed can take place by detection of current flow.
    Type: Grant
    Filed: May 4, 1981
    Date of Patent: February 21, 1984
    Assignee: Thomson-CSF
    Inventor: Jean Claude Frebault
  • Patent number: 4408163
    Abstract: The dimensions and light output of a beam in a shadow mask cathode-ray tube are determined by means of an optical system 7 focussed on a phosphor dot to pick up and record the light generated by a ray 4 passing through a single aperture 6 in the shadow mask 2. The cathode-ray beam 1 is moved so that the whole cross-section of the beam passes the aperture 4. The detected light outputs are plotted to provide an accurate representation of the whole beam.
    Type: Grant
    Filed: December 2, 1980
    Date of Patent: October 4, 1983
    Assignee: International Business Machines Corporation
    Inventors: Peter Burr, Brian D. Chase, Andrew Paton, Brian R. Sowter
  • Patent number: 4381486
    Abstract: An apparatus for checking for electrical frit breakdown in kinescopes includes a support for loosely receiving the kinescope funnel. A floating positioning means closely receives the neck of the kinescope when a kinescope is positioned in the vicinity of the particular location. An orientation mechanism accurately orients the kinescope in the selected orientation and the kinescope is then securely maintained in said location. A fluid-like electrical contact is placed against the outside of the frit seam. A probe having a movable, electrical contact is inserted into the neck of the kinescope and the movable contact brought against the conductive coating on the inside of the envelope. A current flow between the movable contact and the fluid-like contact indicates an electrical frit breakdown.
    Type: Grant
    Filed: February 24, 1981
    Date of Patent: April 26, 1983
    Assignee: RCA Corporation
    Inventors: Merle E. Hertzler, James S. Stelzer
  • Patent number: 4336492
    Abstract: An apparatus for testing an hermetic, glass-like frit seal interposed between the funnel and faceplate of an in-process cathode ray tube is disclosed. A discontinuity in the hermetic seal causes a high voltage breakdown in the seal when a test voltage is applied to the cathode ray tube. The apparatus comprises an elastomeric band which is capable of being stretched over the tube, conforming to the shape of the hermetic seal between the funnel and faceplate. The apparatus also comprises band-mounting means which holds the elastomeric band and stretches the band to fit around the hermetic seal such that the band forms electrical and mechanical contact with the frit seal. The improvement comprises electrically conductive spring means embracing the elastomeric band at its periphery. The spring means are attached to the band mounting means for stretching and relaxing in concert with the elastomeric band.
    Type: Grant
    Filed: May 5, 1980
    Date of Patent: June 22, 1982
    Assignee: Zenith Radio Corporation
    Inventors: Alton J. Torre, Victor R. Schuster
  • Patent number: 4329648
    Abstract: A method for checking for electrical frit breakdown in kinescopes uses a novel probe which is dimensioned to enter into the neck of the kinescopes without contacting the interior of the neck. A movable electrical contact is actuated to a position against the conductive coating on the inside of the tube. A high voltage supply is connected between the movable contact and the frit seal and current flow indicates an electrical frit seal breakdown.
    Type: Grant
    Filed: July 21, 1980
    Date of Patent: May 11, 1982
    Assignee: RCA Corporation
    Inventors: Gerald M. Allaroyce, Ronald N. Moskalczak, Edward A. Gronka
  • Patent number: 4302725
    Abstract: Method of testing a completed cathode-ray tube comprises applying a higher-than-operating voltage between the metal structure around the sidewall of the panel of the tube and the internal conductive coating on the funnel of the tube whereby the panel-to-funnel sealing layer is punctured if it does not have sufficient electrical-breakdown strength.
    Type: Grant
    Filed: March 28, 1980
    Date of Patent: November 24, 1981
    Assignee: RCA Corporation
    Inventor: Jawdat I. Nubani
  • Patent number: 4275347
    Abstract: A precision cathode current regulator for controlling cathode current in a cathode-ray tube having a field effect transistor which is stabilized by an operational amplifier connected in a feedback mode. A second operational amplifier is electrically coupled to the field effect transistor for measuring cathode voltage accurately without affecting the regulated current.
    Type: Grant
    Filed: August 30, 1979
    Date of Patent: June 23, 1981
    Assignee: RCA Corporation
    Inventors: Felta C. Farmer, Jr., Donald P. Knight
  • Patent number: 4220919
    Abstract: A color test pattern, such as a crosshatch line pattern, is generated on the phosphor screen of a color cathode ray tube or a color kinescope. A cathode ray tube display error measuring device comprising at least two optical plates, each transmissive to the light emitted by a different color phosphor of the color kinescope is placed adjacent the phosphor screen. One of the optical plates is rotated until the two images of the test pattern formed by the two plates move into alignment with each other. The amount of rotation is a measure of the amount of error present.
    Type: Grant
    Filed: November 13, 1978
    Date of Patent: September 2, 1980
    Assignee: RCA Corporation
    Inventor: Linus C. Ruth
  • Patent number: 4184111
    Abstract: A bipolar voltage ramp generator applies a linear voltage through a resistor to a solar cell for plotting its current versus voltage (I-V) characteristic between short circuit and open circuit conditions, with automatic stops at the end points. The resistor serves the multiple purpose of providing a current sensing resistor, setting the full-scale current value, and providing a load line with a slope approximately equal to one, such that it will pass through the origin and the approximate center of the I-V curve with about equal distance from that center to each of the end points.
    Type: Grant
    Filed: July 26, 1978
    Date of Patent: January 15, 1980
    Inventors: Alan M. Acting Administrator of the National Aeronautics and Space Administration, with respect to an invention of Lovelace, Gary B. Turner