Cathode-ray Tube Patents (Class 324/404)
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Patent number: 11751316Abstract: 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: GrantFiled: November 5, 2019Date of Patent: September 5, 2023Assignee: GULMAY LIMITEDInventors: Stuart Duncan, Tony Durrant
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Patent number: 11176859Abstract: 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: GrantFiled: March 24, 2020Date of Patent: November 16, 2021Assignee: Synaptics IncorporatedInventors: Masao Orio, Joseph Kurth Reynolds, Xi Chu, Takashi Nose, Hirobumi Furihata
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Patent number: 8332175Abstract: 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: GrantFiled: August 16, 2010Date of Patent: December 11, 2012Assignees: Hong Fu Jin Precision Industry (ShenZhen) Co., Ltd., Hon Hai Precision Industry Co., Ltd.Inventor: Hui Li
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Patent number: 8179138Abstract: 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: GrantFiled: November 20, 2009Date of Patent: May 15, 2012Assignee: Wistron CorporationInventors: Hsiang Chang, Cheng-Hsuan Tsai, Ming-Chang Liu
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Patent number: 8159238Abstract: 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: GrantFiled: September 30, 2009Date of Patent: April 17, 2012Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space AdministrationInventors: Michael J. Krasowski, Norman F. Prokop
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Patent number: 7427887Abstract: 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: GrantFiled: May 13, 2005Date of Patent: September 23, 2008Assignee: Analog Devices, Inc.Inventors: John J. O'Donnell, Michael Christian Wohnsen Coln, Maria del Mar Chamarro Marti
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Patent number: 6661629Abstract: 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: GrantFiled: April 20, 2001Date of Patent: December 9, 2003Assignees: Sony Corporation, Sony Electronics, Inc.Inventors: David Allen Murtishaw, Brian Michael Solomich, Edward Martinez
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Patent number: 6577132Abstract: 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: GrantFiled: November 12, 2001Date of Patent: June 10, 2003Inventor: Jorge Raul Bartulos
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Patent number: 6559591Abstract: 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: GrantFiled: June 5, 2001Date of Patent: May 6, 2003Assignees: Sony Corporation, Sony Electronics, Inc.Inventor: David Allen Murtishaw
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Patent number: 6483313Abstract: 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: GrantFiled: August 1, 2000Date of Patent: November 19, 2002Assignee: Samsung Electronics Co., Ltd.Inventors: Wan-Soo Kim, Chang-Gun Lee
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Patent number: 6456080Abstract: 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: GrantFiled: August 22, 2000Date of Patent: September 24, 2002Assignee: Samsung SDI Co., Ltd.Inventors: Sang-kyun Kim, Sang-mook Kim, Duk-sung Park, Bong-wook Jung
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Patent number: 6211629Abstract: 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: GrantFiled: March 2, 2000Date of Patent: April 3, 2001Assignee: U.S. Philips CorporationInventors: Dirk J. A. Teuling, John H. P. Moors
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Patent number: 6104194Abstract: 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: GrantFiled: February 6, 1998Date of Patent: August 15, 2000Assignees: Sony Corporation, Sony United Kingdom LimitedInventor: Hideo Kato
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Patent number: 5994841Abstract: 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: GrantFiled: October 17, 1997Date of Patent: November 30, 1999Assignee: Welch Allyn, Inc.Inventors: Michael W. Allen, Paul DeLucia
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Patent number: 5929641Abstract: 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: GrantFiled: August 22, 1996Date of Patent: July 27, 1999Assignee: Thomson Consumer Electronics, Inc.Inventors: Paul Kuczer, Richard William Nosker
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Patent number: 5561578Abstract: 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: GrantFiled: May 3, 1994Date of Patent: October 1, 1996Assignee: Mitsubishi Denki Kabushiki KaishaInventor: Susumu Shimoyanagida
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Patent number: 5231489Abstract: 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: GrantFiled: May 6, 1992Date of Patent: July 27, 1993Assignee: Tektronix, Inc.Inventor: Bruce J. Penney
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Patent number: 5115229Abstract: 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: GrantFiled: June 26, 1990Date of Patent: May 19, 1992Inventor: Hanoch Shalit
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Patent number: 5077600Abstract: 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: GrantFiled: October 1, 1990Date of Patent: December 31, 1991Assignee: Sony CorporationInventors: Hiroshi Ichigaya, Satoshi Sato
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Patent number: 4989072Abstract: 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: GrantFiled: January 29, 1990Date of Patent: January 29, 1991Assignee: Sony CorporationInventors: Satoshi Sato, Hiroshi Ichigaya
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Patent number: 4988857Abstract: 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: GrantFiled: May 4, 1989Date of Patent: January 29, 1991Assignee: Hitachi, Ltd.Inventors: Takumi Karasawa, Michio Tsukii, Takashi Atobe, Takaaki Ishikawa, Kazuhiko Mizuno
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Patent number: 4963828Abstract: 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: GrantFiled: February 13, 1989Date of Patent: October 16, 1990Assignee: Hitachi, Ltd.Inventors: Keisuke Kawame, Toshio Asano, Jun Mochizuki
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Patent number: 4893925Abstract: 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: GrantFiled: May 26, 1988Date of Patent: January 16, 1990Assignee: Grumman Aerospace CorporationInventors: Kevin T. Sweeney, Joseph P. Mattal, Mitchell L. Kushner, Robert H. Lemke
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Patent number: 4814858Abstract: 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: GrantFiled: April 6, 1988Date of Patent: March 21, 1989Assignee: Hitachi, Ltd.Inventors: Jun Mochizuki, Toshio Asanoh
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Patent number: 4797619Abstract: 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: GrantFiled: March 13, 1987Date of Patent: January 10, 1989Assignee: EG&G Gamma Scientific IncorporatedInventors: Richard L. Austin, Herbert J. Otto, Frank L. Jones
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Patent number: 4768091Abstract: 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: GrantFiled: October 19, 1987Date of Patent: August 30, 1988Assignee: North American Philips Corp.Inventors: Robert E. Pooler, William R. Kaylor
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Patent number: 4763004Abstract: 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: GrantFiled: January 4, 1985Date of Patent: August 9, 1988Assignee: Fujitsu LimitedInventors: Hiroshi Yasuda, Takayuki Miyazaki
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Patent number: 4754329Abstract: 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: GrantFiled: April 13, 1987Date of Patent: June 28, 1988Assignee: Tektronix, Inc.Inventors: James W. Lindsay, Geoffrey B. Rhoads
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Patent number: 4752825Abstract: 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: GrantFiled: October 10, 1986Date of Patent: June 21, 1988Assignee: Grumman Aerospace CorporationInventors: Robert M. Buckley, Joseph Lovrecich, William R. Biagiotti
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Patent number: 4720282Abstract: 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: GrantFiled: January 12, 1987Date of Patent: January 19, 1988Assignee: RCA CorporationInventors: Thomas L. Chase, Kenneth A. Long
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Patent number: 4709191Abstract: 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: GrantFiled: September 16, 1985Date of Patent: November 24, 1987Assignee: VideocolorInventors: Roger Pieri, Jean C. Fringant
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Patent number: 4677340Abstract: 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: GrantFiled: December 24, 1984Date of Patent: June 30, 1987Assignee: Tektronix, Inc.Inventors: Lawrence J. Miller, Donald P. Chitwood
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Patent number: 4650436Abstract: 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: GrantFiled: October 30, 1985Date of Patent: March 17, 1987Assignee: RCA CorporationInventors: Dennis E. Thro, Mort J. Nierenberg
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Patent number: 4602272Abstract: 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: GrantFiled: November 13, 1984Date of Patent: July 22, 1986Assignee: RCA CorporationInventor: Robert A. Duschl
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Patent number: 4568975Abstract: 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: GrantFiled: August 2, 1984Date of Patent: February 4, 1986Assignee: Visual Information Institute, Inc.Inventor: John H. Harshbarger
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Patent number: 4563649Abstract: 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: GrantFiled: July 11, 1983Date of Patent: January 7, 1986Assignee: Sencore, Inc.Inventor: Barry A. Arenson
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Patent number: 4536792Abstract: 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: GrantFiled: November 23, 1983Date of Patent: August 20, 1985Assignee: Visual Information Institute, Inc.Inventor: John H. Harshbarger
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Patent number: 4459551Abstract: 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: GrantFiled: September 28, 1981Date of Patent: July 10, 1984Assignee: RCA CorporationInventor: Kenneth J. Yakmovitz
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Patent number: 4445872Abstract: 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: GrantFiled: January 18, 1982Date of Patent: May 1, 1984Assignee: RCA CorporationInventor: James G. Ottos
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Patent number: 4439735Abstract: 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: GrantFiled: July 17, 1981Date of Patent: March 27, 1984Assignee: Zenith Radio CorporationInventors: Armando Alvite, Enrico D. Hines, Allan D. Kautz
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Patent number: 4433292Abstract: 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: GrantFiled: May 4, 1981Date of Patent: February 21, 1984Assignee: Thomson-CSFInventor: Jean Claude Frebault
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Method and apparatus for determining beam dimensions at the screen of a shadow mask cathode-ray tube
Patent number: 4408163Abstract: 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: GrantFiled: December 2, 1980Date of Patent: October 4, 1983Assignee: International Business Machines CorporationInventors: Peter Burr, Brian D. Chase, Andrew Paton, Brian R. Sowter -
Patent number: 4381486Abstract: 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: GrantFiled: February 24, 1981Date of Patent: April 26, 1983Assignee: RCA CorporationInventors: Merle E. Hertzler, James S. Stelzer
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Patent number: 4336492Abstract: 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: GrantFiled: May 5, 1980Date of Patent: June 22, 1982Assignee: Zenith Radio CorporationInventors: Alton J. Torre, Victor R. Schuster
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Patent number: 4329648Abstract: 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: GrantFiled: July 21, 1980Date of Patent: May 11, 1982Assignee: RCA CorporationInventors: Gerald M. Allaroyce, Ronald N. Moskalczak, Edward A. Gronka
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Patent number: 4302725Abstract: 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: GrantFiled: March 28, 1980Date of Patent: November 24, 1981Assignee: RCA CorporationInventor: Jawdat I. Nubani
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Patent number: 4275347Abstract: 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: GrantFiled: August 30, 1979Date of Patent: June 23, 1981Assignee: RCA CorporationInventors: Felta C. Farmer, Jr., Donald P. Knight
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Patent number: 4220919Abstract: 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: GrantFiled: November 13, 1978Date of Patent: September 2, 1980Assignee: RCA CorporationInventor: Linus C. Ruth
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Patent number: 4184111Abstract: 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: GrantFiled: July 26, 1978Date of Patent: January 15, 1980Inventors: Alan M. Acting Administrator of the National Aeronautics and Space Administration, with respect to an invention of Lovelace, Gary B. Turner