Abstract: A circuit and method are provided detecting a persistent short circuit in a power MOSFET for the purpose of protecting a load from over-current.

Abstract: A level-shifting inverting circuit provides a blanking signal to Grid 1 of a CRT. The circuit provides the blanking signal from a blanking logic signal according to a voltage transfer characteristic that is substantially similar to the voltage transfer characteristic of a standard CMOS inverter. Also, the level-shifting inverting circuit includes a switch circuit that includes a differential pair. The differential pair has the blanking logic signal at one input, and a bias signal at the other input. The switch circuit is coupled to a voltage divider that provides an output voltage that is pre-determined by a resistor ratio when the switch circuit is open. If the blanking logic signal is low, the switch circuit is open. Conversely, if the blanking logic signal is high, the switch circuit is closed, and sinks current from the voltage divider, causing the output voltage to correspond to a second pre-determined voltage level.

Abstract: A fly-back pulse width adjustment circuit and a method for adjusting the width of a fly-back pulse which are applied to a video signal processing unit realized as one chip are provided. The fly-back pulse width adjustment circuit is built into a video signal processing unit including a video amplifier, an on screen display unit, and a horizontal/vertical synchronous signal processing unit within the video signal processing unit realized as one chip.

Abstract: A display system (10) which includes a CRT feedback current simulating circuit (20) to simulate the cathode feedback current directly from the from the red, green and blue output biases of the video processor (13). Furthermore, the display system (10) applies blanking to the references pulses applied to the CRT output driving stage (16) so that the reference pulses will not be visible during a vertical underscanned condition. Shifting the generation of the cathode feedback current prior to the application of the blanking prevents any significant distortion, modification or skewing of the cathode feedback current sensed by the AKB sensing circuitry (19) of the video processor (13).

Abstract: A cathode ray tube video display comprises a cathode ray tube (CRT) for displaying a video signal (Vin) coupled thereto. A cathode ray tube electron beam blanker (201) is coupled to the cathode ray tube (CRT) and is responsive to a blanking trigger signal (GK) for blanking an electron beam (e) within the cathode ray tube (CRT). A blanking controller (200) is coupled to the cathode ray tube electron beam blanker (201) and generates the blanking trigger signal (Gk) for controlling electron beam blanking, wherein the electron beam (e) is blanked for different durations in accordance with one of a hot and cold start condition.

Abstract: A tracking index cathode ray tube circuit is described, comprising tracking means connected to a shadowmaskless tracking cathode ray tube for deriving a tracking signal therefrom, where the tracking means comprises a modulator demodulator circuit. The tracking signal from the CRT tube is thus modulated, AC coupled to a low voltage and demodulated to obtain a baseband tracking signal for use as a control signal for the electron beam spots on the screen of the CRT tube.

Abstract: A Braun tube discharge apparatus that includes a so-called spot killer function. In the apparatus, an operational amplifier included in a vertical IC receives a vertical ramp signal from a one-chip IC at the non-inversion input terminal. The operational amplifier also receives a part of the output as a negative feedback to the inversion input terminal, and performs differential amplification of it and transmits the results to a vertical deflection coil. At the time a spot killer circuit discharges a remaining electrical charge held by a Braun tube when the power is turned off, a switching transistor is rendered conductive by using a spot killer pulse signal that instructs the activation of the spot killer circuit. When the negative feedback input side of the operational amplifier drops to the ground level, the center DC value of the vertical output signal is increased, and the amplitude is increased.

Abstract: An ultor voltage switching power supply for a cathode ray tube is energized by a low voltage switching power supply. A switching transistor of the ultor voltage switching power supply is disabled when a screen of the cathode ray tube is blanked. An anode capacitance of the cathode ray tube that develops the ultor voltage discharges via a bleeder resistor, when the switching transistor is disabled. As a result, a transient decrease occurs in the ultor voltage. The decreased ultor voltage tends to maintain the screen blanked.

Abstract: Supplementary grid blanking and spot burn protection are provided in a receiver/monitor (10) by a grid bias control circuit (50) including a blanking signal generator (60) that produces a blanking output signal (S1) devoid of any picture representative component whenever a vertical blanking signal (VB) or a horizontal blanking signal (HB) is present. A capacitor (C1) strips DC from the blanking signal and the resultant signal (S2) is applied to a modulation input (84) of a grid bias generator to produce an output grid bias reference voltage (Vr) modulated by the AC component of the blanking signal. The reference voltage (Vr) is coupled via a spot burn protection circuit (100) and a grid coupling circuit (120) to the control grids of three projection kinescopes (16, 18, 20).

Abstract: An apparatus for automatically stabilizing the black level of a displayed picture when (1) an automatic black level stabilizing function is OFF, (2) black level error occurs between at an ON state and at an OFF state and (3) black level variation and picture disturbance occurs during activation and deactivation of the automatic black level stabilizer. Black level variations when the automatic black level stabilizer are OFF is controlled by processing a cathode current in a negative feedback loop and controlling a CRT grid voltage, storing a divided grid voltage during a converging period and processing the grid voltage in another negative feedback loop in order to adjust the grid voltage to an ON state value.

Abstract: A spot is prevented from occurring on the center portion of a cathode ray tube when electric power is turned off by using a voltage charged in a capacitor which are used for outputting a vertical blanking signal in a vertical blanking signal generating circuit of an image display device for displaying an image in use of the cathode ray tube. The present invention is provided with a discharge cut-off element between a negative electric power source and the capacitor for outputting a vertical blanking signal and a discharging element for discharging a charged voltage of the capacitor to the ground. The present invention prevents a charged voltage ofthe capacitor from being discharged until thermoelectrons are not emitted from the cathode so as to supply a negative charged voltage to the first grid of the cathode ray tube continuously, so that a spot is prevented from occurring.

Abstract: A method is provided for reducing a residual spot on a cathode ray tube when a power supply is turned off. The method is executed by applying a holding voltage being no less than the value of the voltage enabling to enhance the back raster luminance and a cut-off voltage, or a voltage of a lower value, to a second grid electrode while the anode voltage is lowered to a predetermined voltage value when the main power supply is turned off.

Abstract: An apparatus and method are disclosed for generating timing pulses to control various functions in a video monitor including the switching of video amplifiers in cathode ray tube (CRT) devices, the control of the phase and frequency of phase locked loops, etc. Unlike previous methods, where switching is timed and controlled by monitoring the retrace voltage level, the system of the present invention monitors the change in direction of current in the retrace tuning capacitor. Monitoring the retrace capacitor current, provides an extremely accurate method for timing in horizontal deflection circuits. The apparatus of the present the invention comprises a small bead inductor placed in the current path of a horizontal retrace capacitor within the horizontal deflection circuit of the cathode ray tube device. Measuring the voltage across the bead inductor allows a very precise monitoring of the current through the retrace tuning capacitor.

Abstract: A kinescope video driver includes a series connection of a main cascode transistor coupled to a cathode of a cathode ray tube and a video signal amplifying transistor. A second cascode transistor is coupled between the main cascode transistor and the video signal amplifying transistor. The second transistor is coupled to the video signal amplifying transistor through a short wire conductor and to the main cascode transistor through a long wire conductor.

Abstract: A video muting control device using a microcomputer, comprising a video mute key for generating a video mute command upon activation by a user; a microcomputer connected to the video mute key, the microcomputer generating a blanking control signal in response to an input of the video muting command, a preamplifier for receiving RGB video signals, the preamplifier generating an amplified video signal in response to a clamping signal and a contrast control signal, and a video mute circuit for muting a video display in response to the blanking control signal by grounding any one of the RGB video signals, the clamping signal and the contrast control signal.

Abstract: A blanking circuit generates a blanking signal by using a vertical fly-back pulse and/or an output signal of a vertical IC. The blanking signal is superimposed on a grid control signal obtained from a fly-back transformer and then provided to a grid control terminal of a CRT. The blanking circuit has an output signal stabilization part to generate a stable signal by restricting a peak value of a signal generated from the vertical IC within a predetermined limit, a pulse width extension part to widen a pulse width of a vertical fly-back pulse generated from the vertical IC and having a constant amplitude and a constant pulse width, and a blanking signal generating part to generate a blanking signal from the signal superimposing the stable signal on the vertical fly-back pulse having a wide pulse width. The blanking signal is superimposed on an output signal of a fly-back transformer and provided to a grid control terminal of the cathode ray tube.

Abstract: A spot killer circuit for a CRT is capable of thoroughly removing any spot persistence and prevents damage to the fluorescent body of the CRT due to inaccurate horizontal and vertical deflection. When the power cord is unplugged, or when the display device is turned off (for example, via remote control key input), the bias voltage of the first grid G1 and the electric potential of the cathode are controlled so as to completely suppress any residual beam current flowing in the CRT. In the case of an inaccuracy (such as total failure) in either the horizontal deflection or the vertical deflection signals, the bias voltage of the first grid and the electric potential of the cathode are controlled to suppress the CRT beam current just as in the case of power shut off. This prevents damage of the fluorescent body in the CRT due to the inaccurate deflection operation.

Abstract: Disclosed is an image display screen controller for the control of a cathode-ray tube. There is produced a blanking logic signal that begins on a leading edge of the frame synchronization square-wave pulse and ends only on the trailing edge of the VFBACK signal generated from the frame flyback pulse without getting interrupted if the frame synchronization pulse and the pulse VFBACK corresponding to the frame flyback do not overlap. An RS flip-flop circuit is activated on the leading edge of the frame synchronization square-wave pulse VSYNC and is reset only by the trailing edge of the frame flyback pulse VFBACK. The output of the RS flip-flop is applied to an input of an OR gate that receives other inputs, notably the synchronization square-wave pulses and the line and frame flyback pulses. If the scanning disappears for example by the destruction of a transistor, the absence of a frame flyback pulse will prevent the reactivation of the beam and hence prevent a dot of the screen from being burned out.

Abstract: A horizontal retrace time adjustment pulse generating circuit includes a microcomputer for outputting a horizontal flyback signal and an analog voltage based on an input horizontal synchronizing frequency; oscillation duty adjusting circuit for outputting a duty-cycle adjusting signal based on the analog voltage of the microcomputer; a monostable multivibrator for outputting a rectangular wave based on the horizontal flyback signal of the microcomputer and the duty-cycle adjusting signal of the oscillation duty adjusting circuit; feedback signal detecting circuit for detecting a horizontal flyback pulse from a horizontal deflection circuit and outputting the detected signal; and signal coupling circuit for coupling the rectangular wave of the monostable multivibrator and the detected signal from the feedback signal detecting circuit and outputting a result of the coupling as a time control pulse for horizontal retrace.

Abstract: An arrangement for reproducing a composite blanking or sync signal includes a vertical deflection circuit having a supply boost stage. A first pulse voltage at a vertical rate is derived from an output signal of the boost stage. The vertical rate, first pulse voltage is coupled to a base terminal of an emitter follower via a voltage divider for producing a leading edge of an output pulse voltage of the emitter follower. The vertical rate first pulse voltage is also coupled via an R-C network to a regenerative switch. The regenerative switch is coupled to the base terminal of the emitter follower for producing a trailing edge of the output pulse voltage of the emitter follower. The trailing edge is produced after a predetermined interval has elapsed from the leading edge. The output pulse voltage of the emitter follower is combined with a horizontal rate pulse voltage for producing the composite sync signal.

Abstract: A circuit for adjusting a horizontal retrace time and limiting a pulse peak in a display device includes a microcomputer for receiving a horizontal synchronous frequency and converting the horizontal synchronous frequency into a first voltage. A pulse generator compares the first voltage provided from the microcomputer with a triangular waveform to adjust a width of a retrace time adjusting pulse. A transformer receives an output voltage from the pulse generator to generate an induced voltage. A switching unit performs a switching operation in accordance with a magnitude of the induced voltage provided from the transformer. A clamping unit clamps the induced voltage provided from the transformer to limit a voltage peak value. A charging/discharging unit performs charging and discharging operations according to an output of the switching unit.

Abstract: A spot removing circuit for a display device is disclosed. The spot removing circuit comprises a rectifying and smoothing portion for rectifying and smoothing the voltage outputted from a flyback transformer, a capacitor for charging a voltage supplied from a power supply and discharging the charged voltage when the power supply switch is turned off, and a grid control portion for supplying a grid terminal with the voltage outputted from the rectifying and smoothing portion when a power supply switch is turned on and for supplying the grid terminal with the voltage discharged from the capacitor plus the output voltage from the rectifying and smoothing portion when the power supply switch is turned off so that a spot can be prevented from appearing on a display screen when the power supply switch of the display device is turned off.

Abstract: A vertical deflection circuit includes a first pin which receives a forward scanning voltage having a first level and a first frequency. During a flyback period a second pin receives a flyback voltage having a second level higher that the first level and a second frequency higher than the first frequency. A third voltage source provides a first pulse. A switch means selectively couples the first pin and the third voltage source in response to a vertical blanking signal. The vertical blanking signal is differentiated to provide a differentiated signal and a voltage divider applies the differentiated signal to the switch to apply the first pulse to the first pin.

Abstract: A first grid muting circuit for a monitor display for smooth muting operation of a muting circuit portion to provide a stable picture to a viewer can be favorably applied to a monitor circuit by a microcomputer for supplying a muting signal to blocks per corresponding modes, a contrast muting circuit portion for muting the muting signal to a predetermined level, a video circuit for outputting the muted contrast signal as a video signal, a first grid drive portion for driving a first grid circuit, and the first grid circuit for outputting a first grid signal for controlling a cathode ray tube to a vertical blanking circuit in accordance with a control signal of the first grid drive portion.

Abstract: A scanning circuit which utilizes blanking pulses between flyback pulses in a display device includes a line blanking circuit which prevents the generation of spurious blanking pulses by ringing in the blanking pulses. The line blanking circuit includes a capacitor for storing a reference voltage. A comparator is responsive to the reference voltage and to the flyback pulses and provides the blanking pulses when the flyback pulses exceed the reference voltage. The comparator is prevented from resetting for a preselected time period after the falling edge of the blanking pulse and spurious blanking pulses can not be generated during the preselected time period.

Abstract: Disclosed is a color printer which uses a CRT to print on photographic medium. The printer contains a uniformity EEPROM that corrects for brightness of each position on the CRT. If a position cannot be corrected, a blank code is placed in the EEPROM at the position, to blank the CRT at the position. Adjacent positions are intensified, or positions in the same column on other CRT rows are intensified to correct for the defective position. The printer also allows the uniformity information to be field updated by printing an entire page of each primary color, sending these pages back to the factory, scanning them into a computer system using a document scanner, analyzing each page, creating new uniformity data from the analysis, and sending this data back to the printer where it is loaded into the uniformity EEPROM.

Abstract: The length of the retrace portion of a vertical sawtooth signal is controlled by a microprocessor. In this way, the same type of an integrated circuit that includes the sawtooth generator can be used for generating the sawtooth signal required either for a switch or a non-switch vertical deflection circuit output stage.

Abstract: An electron gun and a high tension switch permits the achievement of high-power electron beams which are ON-OFF modulated by DC up to frequencies exceeding kHz. The electron gun has a cathode, at least two accelerating electrodes, a cathode heater, and a possible focussing system. The or each accelerating voltage, generated by any source, which may in the case of space applications also be a tether, is applied between accelerating electrodes and cathode, with the exception of an appropriate accelerating electrode to which there is applied, by of the switch, alternately its accelerating voltage or the same voltage as that of the cathode, obtaining an ON-OFF modulation of the electron beam emitted by the gun.

Abstract: A spot killer circuit for a cathode ray tube having blanking function is configured to be provided with a positive voltage source, a negative voltage source, two diodes, condensers and a resistor in order to perform blanking in horizontal scanning or vertical scanning by using a first grid of the cathode ray tube. In the configuration, the two diodes are inserted in series between the negative voltage source and the first grid, and a first condenser is inserted between a junction of the two diodes and the positive voltage source. A resistor is connected in parallel with the diode connected to the first grid, and a blanking signal is applied to the first grid through a second condenser.

Abstract: Circuit arrangement including a parabolic generator for supplying a periodic, substantially parabolic signal to an output terminal during a trace time and an arcuate signal generator for supplying an arcuate signal, which has the shape of, for example, a half sine wave, during a retrace time. At the start of the retrace time, the arcuate signal and its derivatives are given values which are substantially equal to the corresponding values of the parabolic signal at the end of the trace time. The arcuate signal generator is adapted to generate the arcuate signal in a time-discrete manner under the control of switching pulses supplied by a pulse circuit. The pulse circuit is adapted to supply a constant number of switching pulses for generating the arcuate signal in spite of variations in the retrace time, so that the arcuate signal and its derivative assume values which are substantially equal to the corresponding values of the parabolic signal at the start of the trace time.

Abstract: A voltage at a control grid of a cathode ray tube is generated at a blanking level to provide beam current blanking when horizontal deflection loss occurs. The control grid voltage at the blanking level is developed in a capacitor prior to an instant in which the horizontal deflection loss occurs. When the capacitor voltage is applied to the control grid to provide the blanking level, the capacitor is discharged slowly. To maintain the capacitor charged, prior to such instant when horizontal deflection is lost, the capacitor voltage is not applied to the control grid as long as the horizontal deflection is normal, regardless of whether vertical deflection loss occurs. Either horizontal deflection loss or vertical deflection loss will disable a video driver stage that controls the cathode of the cathode ray tube for providing additional beam current blanking capability.

Abstract: A source of kine supply voltage is coupled to a video amplifier that drives a cathode of a cathode ray tube of a projection television receiver via a self biasing diode. When, due to, for example, a fault condition, the kine supply voltage is lost, the self biasing diode decouples the cathode of the cathode ray tube from a supply return terminal of an ultor supply voltage to form a high impedance, low capacitance at the cathode of the cathode ray tube. A beam current develops a self biasing voltage at the cathode of the cathode ray tube that substantially reduces the beam current to provide protection against a damage to a screen of the cathode ray tube.

Abstract: The invention relates to a device for the optical recording of rapid proceses with a TV camera, which comprises means for deviating and suppressing the beam, in order to make the scanning beam run successively and cyclically over N lines of a picture plane on which the processes are projected.A cyclic line counter (14) carries out one counting step for each line pulse and supplies a counting end pulse after p line pulses respectively, N/p being in integer >>1.The end-of-count pulse is applied to the beam suppression circuit (13) of the TV camera (1) for the picture beam suppression and to a sawtooth generator (12), which controls the vertical deviation (4) of the beam.

Abstract: A blanking circuit for use in a television receiver designed for video signals of both the HDTV and double-speed scanning NTSC systems comprises a sawtooth generator, a reference voltage generator, a comparator for comparing the sawtooth signal with the reference voltage, a switch for selectively changing the relative level of the reference voltage and the sawtooth signal in conformity with the input broadcasting system, and with the output of the comparator supplied as a blanking pulse to a video signal processor. Due to selective change of the time constant of the sawtooth generator or the change of the threshold level of the reference voltage, a proper blanking pulse can be produced with high precision to prevent losing the image on the monitor CRT screen, and an adequate blanking interval is exactly obtained.

Abstract: A femtosecond sampling oscilloscope includes a femtosecond laser for generating a pulse of light in the femtosecond range and a beam splitter for splitting the pulse of light into pulses traveling along first and second beam paths. A photoconductive switch disposed along the first beam path is used to produce an electrical stimulus output at a first output port, an electrical pulse output at a second output port and an optical output at a third output port. A photomultiplier tube having a strip line photocathode receives the pulse of light traveling along the first beam path. An input port is coupled to the photocathode. In use, the output signal at one of the output ports is connected to a test device producing a test voltage signal which is applied to the input port. When the test voltage signal and the light pulse traveling along the second path intersect on the photocathode in space and time, an electrical signal output is produced at the photomultiplier tube.

Abstract: A projection cathode ray tube burn protection circuit includes a buffer transistor supplied with a 60 Hz square wave signal from an optical coupler. A PNP and NPN combination of transistors full wave rectifiers the buffer output. The rectified signal is divided down to reduce the magnitude of the alternating current components therein and applied to the base of a switch transistor that is normally maintained in saturation for swamping out the alternating current components. The switch transistor drives a high voltage shut down transistor and a blank transistor for shutting down the high voltage generating system and for blanking the cathode ray tube, respectively, in the event the power input to the optical coupler is disrupted.

Abstract: The screen grid of a CRT is connected to a blanking pulse amplifier by means of a resistor and a capacitor. This screen grid is also connected to the anode of a diode. The cathode of the diode is coupled to the ground by means of a ripple-removing capacitor, and is also connected by means of a resistor to the tap of a variable resistor for controlling the screen luminance of the CRT. During each scanning period of the CRT, the diode is turned on, thus equivalently connecting the ripple-removing capacitor to the screen grid. During each blanking period of the CRT, the diode is turned off, thereby disconnecting the ripple-removing capacitor from the screen grid.

Abstract: A device enables to reproduce without flicker mixed signals from VT and/or BTX decoders during the reproduction of television signals (mixed operation). This is obtained by a video frequency scanning field compensation in the vertical direction effected by a video frequency additional connectable scanning amplifier which supplies a reduced inductivity additional scanning winding.

Abstract: A blanking pulse generation circuit for generating a blanking pulse with a large duration is disclosed. The blanking pulse generation circuit includes a flyback pulse shaping circuit for shaping a flyback pulse and generating a rectangular wave signal and a front pulse generation circuit for adding a front pulse to the front edge of the rectangular wave signal. The blanking pulse is formed by the blanking pulse generation circuit for adding a front pulse to the rectangular wave signal.

Abstract: A device for isolating an electrical instrument from an input voltage signal at a floating potential. The device includes a transformer with a center-tapped primary winding, a center-tapped secondary winding and a core magnetically coupling the primary and secondary windings. The input voltage signal is applied to an input terminal coupled to the center tap of the primary winding. A modulator circuit is connected to the primary winding for alternately applying the input voltage signal to opposite sections of the primary winding by means of FETs, or the like, isolated from a control circuit by a transformer, the control circuit alternately switching the modulator circuit at a suitable modulating frequency.

Abstract: A digital-to-analog converter comprises a current source for supplying a current of predetermined magnitude to a circuit node, and a switch connected to the circuit node, and defining a first current path leading to a reference potential terminal and a second current path leading to an output terminal. The switch has an input terminal, at which it receives a first digital signal of one binary digit for conversion to analog form, and also has a reference terminal, and has a first condition, when the voltage at the reference terminal is higher than that at the input terminal, in which the current supplied to the circuit node is delivered to the output terminal, and a second condition, when the voltage at the reference terminal is lower than that at the input terminal, in which the current is delivered to the reference potential terminal.

Abstract: A device for isolating an electrical instrument from an input voltage signal at a floating potential. The device includes a transformer with a center-tapped primary winding, a center-tapped secondary winding and a core magnetically coupling the primary and secondary windings. The input voltage signal is applied to an input terminal coupled to the center tap of the primary winding. A modulator circuit is connected to the primary winding for alternately applying the input voltage signal to opposite sections of the primary winding by means of photo FETs or the like for alternately switching the modulator circuit at a suitable modulating frequency. A demodulator circuit is connected to the secondary winding for alternately connecting each end of the secondary winding to a common return point to demodulate the output signal from the center tap of the secondary winding by means of FETs or the like.

Abstract: A cathode ray tube protection circuit for a projection TV generates a signal which may be used to blank the tubes in response to a loss or reduction in beam deflection. Signals representative of vertical and horizontal deflection currents are provided. A reference signal is combined with the deflection representative signals to provide a signal having a predetermined amplitude. If the deflection current changes in any of the deflection yokes, the combined signal will change in amplitude. This change in amplitude is detected and used to generate a disabling or blanking signal for the kine driver circuits.

Abstract: A line scanning circuit for an electrostatically deflected cathode ray tube uses two integrator circuits having single transistor amplifiers for complementary conductivity types with capacitive feedback to provide balanced sawtooth drive waveforms. The charges on the capacitors are reset by pulses at line frequency and the forward sweeps of the sawteeth are produced by current flowing from the input of one integrator to the input of the other integrator. A variable resistor in the current path provides width control and a transistor connected in series with the current path enables dynamic adjustment of the scan to be provided to suit the scanning characteristics of a flat cathode ray tube. A signal from the field scanning circuit during flyback is applied to turn off the transistor in the current path so that the spot is returned during field flyback up one side of the screen.

Abstract: During the horizontal retrace scan period of a scanning beam in a television pickup tube, the beam current is increased to the maximum possible value to recharge the target layer, and the cathode voltage is raised by a few volts to prevent readout of normal video. Also, the scanning beam path may be modified to insure that every area of the image is scanned by the retrace scan prior to being scanned by the active picture scan.

Abstract: A system for preventing phosphor burn in a cathode ray tube (CRT) without a shadow mask such as used in a projection television receiver is disclosed. Horizontal drive circuit failure or the intermittent operation thereof is detected by means of a fast falling, horizontally derived, high voltage sweep transformer output which results in the application of a stable positive voltage to raster blanking circuitry for the duration of horizontal drive circuit failure or intermittent operation. Short time constant coupling circuitry permits the near simultaneous shutdown of the CRT upon detection of a horizontal drive circuit malfunction in avoiding the burning of a vertical line on the unprotected phosphor-coated faceplate of the CRT.

Abstract: A non-fade display for a CRT which includes a brightened dot, or "bouncing ball", is described. The refreshed display makes use of relatively short persistence phosphors, together with a digital controller to momentarily stop a trace at a predetermined point corresponding to the newest data sample point, increase its intensity to form the brightened dot, follow the brightened dot with a blanked zone, and then continue with the older part of the trace.BACKGROUND OF THE INVENTIONThe present invention relates to a display system utilized in conjunction with a cathode ray tube (CRT). In particular, the invention is used in conjunction with CRTs designed to display data including a periodically updated trace.In various types of apparatus, including oscilloscopes and monitoring devices, such as patient monitors, a CRT is used to display a trace representative of the data being monitored.

Abstract: An electronic image framing circuit is described for eliminating the visible effects of pincushion distortion at the edges of a television image. Toward this end, portions of video lines which extend beyond a selected straight line image boundary are blanked by a pulse processor. The pulse processor responds to conventional horizontal rate and vertical rate pulses for developing blanking pulses whose widths are varied at a vertical rate. The modified blanking pulses are applied to a conventional blanking circuit for blanking the portions of video lines which extend beyond the desired image area. A parabola generator is also described for use in developing the modified blanking pulses.

Abstract: An integratable CRT spot cut-off network is described for use in a television receiver. The network establishes a reference current for biasing up the receiver's G.sub.1 grid when the supply voltage comes up, and a bypass capacitor coupled to the grid charges toward the supply voltage. When the receiver is turned off, the network terminates the reference current as the supply voltage starts to collapse and prevents the bypass capacitor from discharging. The charge stored on the capacitor reverse biases the grid to cut off the receiver's beam current.

Abstract: A multi charged particle beam writing method includes calculating first shot positions of multiple beams, each of which includes a distortion amount of an irradiating corresponding beam, in a case of irradiating each beam, based on control grid intervals, calculating first condition positions based on a pre-set condition, each of which is arranged in a corresponding first region surrounded by closest second shot positions of 2×2 in length and width of the first shot positions, calculating, for each of second regions respectively surrounded by closest second condition positions of the first condition positions, an area density of a figure pattern in overlapping with a second region concerned, calculating an irradiation amount or an irradiation time of each beam whose corresponding first shot position is in a corresponding second region, based on an area density, and writing a pattern by irradiating a beam of the calculated irradiation amount or time.