Abstract: A digital image correction device in which correction data at correction points corresponding one by one to positions on a CRT screen displayed by raster scanning system is stored as a relation pattern expressing the relative relation with the correction data of the adjacent correction point as one-bit data such as UP/DOWN, and on the basis of this relation pattern, a correction signal is generated for boosting, lowering or holding the voltage of the correction signal at each correction point as compared with the voltage at the adjacent correction point.

Abstract: An improved convergence correction apparatus for a projection television and a method thereof which are capable of moving a convergence correction data corresponding to modes to a memory during a mode switching without increasing the capacity of the memory in a projection television, so that it is possible to fabricate a more compact system, for thus reducing the fabrication cost.

Abstract: A television system performs beam convergence in video displays. The system is implemented through one or more convergence sensors, which are exposed to two distinct convergence test patterns. The output signals from the sensors when exposed to the two test patterns are used in beam convergence calculations. The test patterns are selected to reduce the dynamic range requirement for an A/D converter in the television system supplied with the sensor output signals.

Abstract: A method is proposed for obtaining signals in electronic devices by means of interpolation between interpolation point values (W0 to W12), the interpolation point values (W0 to W12) being distributed linearly over a region. A number of interpolation values are calculated in each case at a specific interval between the interpolation point values (W0 to W12). The calculation of the interpolation values is then performed as follows: Firstly, a correction step value (a to 1) is determined in each case for an interval bounded by two interpolation point values (W0 to W12) by linear interpolation between these interpolation point values (W0 to W12) . These correction step values (a to 1) are calculated for all intervals. The calculation of the interpolation value in the current interval is then performed such that apart from the correction step value (a to 1) for the current interval use is also made at least of the correction step value (a to 1) of the preceding and/or of the following interval.

Abstract: A color display device having a color display tube with a display screen, comprising an electron gun for generating three co-planar electron beams, and a deflection system which, in operation, generates deflection fields for scanning the display screen, and an element influencing the landing angle of the outermost beams, for example an element generating, in operation, a 45.degree. magnetic 4-pole field, and comprising a correction device which supplies a signal to the element influencing the landing angle, which signal is derived from the video information (for example a signal which is proportional to the strength of the instantaneous beam current) in order to remedy landing errors caused by space-charge repellence between beams.

Abstract: A system and method for performing convergence calibration, wherein the test patterns generated during the convergence procedure illuminate only one convergence sensor at a time. Since only one sensor is illuminated at a time, there is no need to switch among sensors in order to obtain sensor readings, and the sensors can share an A/D converter without such switching. Therefore, in a convergence apparatus according to the invention two or more sensor couplings are simply coupled to a shared coupling which is, in turn, coupled to the input of a shared A/D converter. Thus, no switching circuitry is required, it is not necessary to perform a sensor/sensor coupling association routine, and there is no need for a convergence subsystem memory.

Abstract: The present invention relates to a multi-frequency display system and method for providing sharpness enhancement. The system comprises a sharpness enhancement circuit that is configured to receive a first and a second input video signal, where the first input video signal operates at a first frequency, and the second input video signal operates at a second frequency. The system further comprises a controller circuit coupled to the sharpness enhancement circuit, that is configured to generate a first sharpness enhancement signal corresponding to the first frequency and a second sharpness enhancement signal corresponding to the second frequency. The sharpness enhancement circuit generates a first control signal in response to the first input video signal and the first enhancement signal, and the sharpness enhancement circuit generates a second control signal based on the second input video signal and the second enhancement signal.

Abstract: An apparatus for measuring image qualities of a color display unit has an image quality sensor comprising a color video camera for imaging a display screen of the color display unit and a fixed-focus lens combined as an imaging lens with the color video camera. Image qualities of the color display unit are measured based on an image signal generated by the color video camera, and an image signal required to measure the image qualities is generated and supplied to the color display unit.

Abstract: After analog-to-digital conversion, a luminance signal 103 and a chrominance signal 109 are stored in a line memory circuit 128. Such stored signals are read out of said line memory circuit, using a read clock 124 obtained by parabolically modulating a read frequency with both the horizontal period and the vertical period. The read-out digital signal is again converted into an analog luminance signal 132 and analog color difference signals 135, 136 by digital-to-analog conversion. By this procedure, inner pincushion distortion or inner barrel distortion is corrected. Since such distortion is corrected by modulating an image signal itself by digital processing, no circuit drift due to the conventional analog correction occurs and no analog circuit design such as troublesome setting of parts constants is required.

Abstract: A convergence correction circuit for use in a projection CRT of the electrostatic focusing type, including a neck portion provided with a sub-deflection yoke for convergence correction. A coupling correction filter and an eddy current correction filter are interposed between a path of a convergence correction signal. The coupling correction filter corrects a change in correction frequency characteristic due to an influence of coupling of a sub-deflection yoke and a deflection yoke, and the eddy current correction filter corrects a change in correction frequency characteristic due to an influence of an eddy current caused in an electrostatic convergence electrode by a magnetic field generated in the sub-deflection yoke. When a coil of the sub-deflection yoke is supplied with a current proportional to an output of the correction filter, convergence correction is performed.

Abstract: A digital convergence correction device converts correction data into serial data by using a parallel/serial converter, and further converts the serial data into an analog correction signal by using a serial input type digital/analog converter, and outputs the analog correction signal in order to correct misconvergence.

Abstract: Image display apparatus (2) comprising at least one display projector for displaying an image, signal generator means for generating a control signal for controlling the intensity of the image, modulator means (4, 6) for generating a modulation waveform for modulating the intensity of the image, and adjustor means (8, 10) for adjusting the modulation waveform to improve the performance of the modulation waveform at various image intensities, the image display apparatus being such that it uses different modulation waveforms for various image intensities, it uses a proportion of at least one modulation waveform in dependence upon the control signal, and it uses the resultant modulation waveform to modulate the control signal.

Abstract: The color matching methods and systems according to the current invention accomplish accurate color matching by separating causes for creating color discrepancies in a predetermined color patch on an image-carrying medium and a color monitor display. In general, the chromaticity values of the predetermined color patch are measured under a standard calorimeter light source whose luminance is different from that of ambient light. The corresponding color is displayed based upon the luminance of the standard light. However, ambient light does not generally have the above luminance. Thus, when the color display is compared against the color patch under ambient light, the colors do not appear identical. To solve this and other problems, the current invention discloses methods and systems to adjust the display signals based upon the luminance of ambient light.

Abstract: The present invention relates to a multi-frequency display system and method for providing color convergence. The system comprises a convergence circuit that is configured to receive a first set and a second set of color input signals. The first of color input signals operates at a first frequency, and the second set of color input signals operates at a second frequency. The system also comprises a controller circuit coupled to the convergence circuit, that is configured to generate a first convergence signal corresponding to the first frequency and a second convergence signal corresponding to the second frequency. The convergence circuit generates a first control signal in response to the first set of color input signals and the first convergence signal. The convergence circuit generates a second control signal based on the second set of color input signals and the second convergence signal.

Abstract: In a CRT display and a television set having the same, horizontal/vertical synchronizing signals are separated from a video synchronizing signal in a synchronizing separation circuit, and position information S of a vertical frame is generated on the basis of the horizontal/vertical synchronizing signals in a count-down processor and then converted to corrected vertical frame information W in a function circuit to output a vertical deflection waveform signal and a horizontal deflection correcting waveform signal. Further, the corrected vertical frame information W is compared with predetermined voltages in comparators to detect an effective frame range in the vertical direction.

Abstract: A television picture image processing apparatus includes a horizontal edge gate pulse generator, a vertical edge gate pulse generator, an AND combiner for ANDing horizontal and vertical edge gate pulses applied thereto respectively from the horizontal and the vertical edge gate pulse generators, a sawtooth pulse generator, an amplifier for controlling the gain of sawtooth pulses from the sawtooth pulse generator in accordance with an external DC voltage, and a luminance processor. The apparatus prevents picture quality of a television set from being degraded due to a poor contrast and brightness occurring in each corner of a television picture screen.

Abstract: A frame size regulating circuit provides high picture quality to a viewer by regulating a frame width according to a picture brightness signal and pulsewidth modulation signals. The circuit includes a microprocessor for generating pulsewidth modulation signals for respectively regulating horizontal and vertical sizes of the frame according to horizontal and vertical sync signals from the external, and a horizontal-size control signal generator part for generating a horizontal size control signal for regulating the horizontal size according to the first pulsewidth modulation signal of the microprocessor and a picture brightness signal from a flyback transformer.

Abstract: Apparatus and method for performing convergence calibration in a system that uses multiple beams to generate a video display on a screen. A photosensor is exposed to first and second distinct convergence test patterns which have illuminated areas that cover approximately first and second halves of the photosensor, respectively. For each beam, first and second output signals are generated by the photosensor when the first and second test patterns are generated, respectively, and alignment is determined on the basis of the output signals. The test patterns are selected in such a manner as to reduce the dynamic range requirement for the A/D converter(s) that digitize photosensor output signals. Optionally, measurement resolution is enhanced by varying test pattern density in accordance with the A/D converter input signal level so as to maintain a generally constant A/D converter input level.

Abstract: A full color display optical system with chromatic aberration correction. The system includes a wide spectral band image source such as a cathode ray tube or Ferroelectric liquid crystal array, a field sequential Red-Green-Blue shutter, and an optical module for projection. The optical module corrects longitudinal chromatic aberration and higher order monochromatic and chromatic aberrations. Lateral chromatic aberration and chromatic distortion are compensated electronically by the color sequential shutter and the image source with a pre-distorted image.

Abstract: A plurality of photo detectors are arranged outside the display screen of a projection display apparatus having a built-in digital convergence correction system and a function for adjusting data in the frame memory so as to coincide the photoelectric devices of the photo detectors with the adjustment patterns is provided. The adjusted data when the convergence on the entire screen of the display is adjusted and the adjusted data when the convergence is adjusted by the adjustment function before misconvergence is generated are memorized beforehand. When misconvergence is generated, the convergence is adjusted by the adjustment function again, and a corresponding correction value is obtained on the photo detector by calculating the adjusted data at this time and the prememorized adjusted data, and a correction value on the entire screen is obtained by executing an interpolation calculation from this correction value, and the misconvergence on the entire screen is corrected.

Abstract: The invention provides an external sensor that is employed by the user of a video display when performing convergence calibrations at various points within the display's viewable area. The external sensor is placed on the screen by the user while a convergence procedure is undertaken by the video display. Readings taken by the sensor during the procedure are relayed to the display's convergence algorithm(s) by means of a suitable coupling, thereby allowing for convergence calculations about the user selected point. When convergence about the point has been achieved, the user may move the sensor to a new point on the screen to initiate convergence procedures about the new point, or remove the sensor from the screen to facilitate viewing.

Abstract: A rigid ferrite-containing ring and plastic holder are described for mounting on the neck of a color cathode ray tube (CRT) which ring is to be custom magnetized in order to provide correction of static convergence, color purity and/or frame errors in the CRT. The holder is provided with depressible tabs which releasably secure the ring to the holder. The holder is mounted on the neck of the CRT in the vicinity of the main focusing gap of the electron gun of the CRT, using an adhesive.

Abstract: When a required color image is to be output from a color image output device using an image input device for outputting color separation value signals corresponding to a read color image, if a change in image reproduction environment is detected by each of sensors provided to these devices, learning processing is properly executed. Using neural networks of a color conversion section and a color correction section which are optimized by the learning processing, a signal output from the image input device is color-converted and color-corrected. The color-corrected image signal (color separation value signals) is supplied to the color image output device to reproduce a color image.

Abstract: When two projecting units or more project two pictures or more obtained from video signals and luminance levels of projected pictures at an overlapped portion thereof are adjusted, a picture to be adjusted is selected from the projected pictures. One of processings for adjusting a correction start point of a correction data, a correction end point thereof and an inclination of a correction curve thereof to be used for a picture adjustment is selected. When the positions of a correction start point and/or a correction end point of the correction data are adjusted by using a remote controller unit or the like, a mark data is superposed on the correction start point and/or the correction end point of the correction data to display a mark formed based on the mark data on the screen together with the projected pictures. Thus, the picture is adjusted by displaying the marks together with the projected pictures.

Abstract: A field memory stores convergence adjusting data which corresponds to a plurality of points on a display screen. An interpolation calculation circuit creates interpolation convergence adjusting data for correction points located between adjacent adjusting points, using a plurality of adjusting data items and interpolation coefficients. The output of the interpolation calculation circuit is subjected to digital/analog conversion and passed through a low-pass filter, thereby forming a convergence correction signal. This correction signal is supplied to each deflection coil. At the time of creating interpolation adjusting data for a point located between adjusting points, an optimal interpolation coefficient is output from a ROM or a ROM, depending upon whether the point is included in the odd or even field.

Abstract: Among the total sampling points for digital convergence, a portion are selected as seed points. Correction data of each of the selected seed points is efficiently stored in a first memory. The correction data of the sampling points which are not stored is interpolated using operation values. The operation values for the interpolation operation are stored ahead of time in a look-up table. Thus, rather than using dedicated calculating circuits for performing an interpolation operation, hardware is simplified and operation speed is enhanced.

Abstract: Digital convergence correction system for correcting misconvergence on a screen of a multi-mode projection television, including a first memory part for storing adjustment point data for every mode of multi-modes, a second memory part for storing convergence correction data in accordance with the adjustment point data, a control part for producing the convergence correction data using the adjustment point data stored in the first memory part for writing the convergence correction data on the second memory part and outputting the convergence correction data stored in the second memory part, and a time sharing processing unit for controlling the control part to share time in producing the convergence correction data and renewing convergence correction data in the second memory part and outputting the convergence correction data stored already in the second memory part for preventing overlap of the producing and storing time and the outputting time.

Abstract: A device is provided for measuring eccentricities of electron beams of a color cathode ray tube. The device detects, in a magnetically neutral environment, by use of a luminance pattern formed on the screen of the tube, eccentricities of electron beams, ascribable to electron gun electrode port production and assembly errors. The device has rapid measuring capabilities and may be used on a production line.

Abstract: The invention presents a digital convergence apparatus of high precision, relating to a digital convergence apparatus applicable to a color display device for displaying various image information in various signal formats, and capable of correcting convergence at high precision to correct color deviation of color image, comprising frequency detecting means for detecting frequency of synchronizing signal included in input signal in every input signal entered from outside, digital convergence correction data operating means for operating digital convergence correction data for display means for displaying the input signal as image, corresponding to the frequency detected by the frequency detecting means, using horizontal synchronizing signal or vertical synchronizing signal of the synchronizing signal as timing signal, and pattern signal generating means for generating a convergence adjusting pattern corresponding to the digital convergence correction data from the correction data operating means, wherein the d

Abstract: A digital convergence correcting circuit for digitally correcting a convergence of R, G and B, which includes a memory for storing only seed data and a convergence correcting part for interpolating and latching the stored seed data with 16 points of sampling data by using a predetermined equation and then interpolating the latched sampling data in a vertical direction with as many horizontal lines as are necessary according to the particular broadcasting system. Since only seed data is stored at the memory, the size of the memory is minimized.

Abstract: A system for transforming coordinate systems in an automated video monitor alignment system includes a camera and computer to capture an image of the display bezel surrounding the cathode ray tube and of the image displayed on the CRT. Three dimensional models of the CRT tube and display bezel are used to compute and compensate for camera perspective. Camera pixel data can then be transformed to `flat plane` coordinates. When the relative orientation of the camera and CRT are corrected, the effects of parallax can be eliminated, allowing more accurate inspection, measurement, and lower cost fixturing on the production line. Thus, an accurate coordinate transformation from a camera-referenced coordinate system to a monitor-referenced coordinate system is made. Correction factors for correcting errors due to refraction can also be generated empirically in accordance with the present invention. Slope coordinate data is generated for a sample monitor for predetermined slope coordinate locations on the tube face.

Abstract: A method for correcting digital convergence performed with respect to four modes of NTSC, ED, MUSE and ZENITH only by adjusting the convergence for a single mode on a software basis includes the steps of adjusting a specific mode and calculating correction data based on adjustment data for the specific mode and storing adjustment data and correction data in memory, and calculating correction data of other modes based on correction data stored for the specific mode, thereby remarkably improving the accuracy of the convergence, facilitating adjustment time and adjustment itself, simplifying the system to cut down the price of the system while enabling digital convergence of a multi-sync projection television to apply it to household use and monitors for personnel computers and video conferencing.

Abstract: A convergence correcting device in a CRT display apparatus is free from any necessity of adjustment of a convergence correction rate even if a raster size is changed. The convergence correcting device generates a modified blanking pulse having a pulse width which becomes larger as an amplitude of a deviated voltage becomes larger, and generates a convergence correction signal in accordance with the modified blanking pulse.

Abstract: A digital convergence apparatus using two different kinds of data to correct the convergence of odd and even scanning lines, respectively. A first memory stores data for the convergence correction corresponding to plural correction executing points aligned in the horizontal or vertical direction of a screen. A first static convergence data memory stores a first static convergence correction data for correcting the entire screen in the same direction, a second static convergence data memory stores a second static convergence correction data different from the first static convergence correction data only by an amount corresponding to the distance between the scanning lines. Selecting means select the output of the first or the second static convergence data memory according to the odd field period or the even field period. Adding means add the output of the selecting means to the data stored in the first memory.

Abstract: A convergence adjustment circuit and a projection type display apparatus provided with convergence adjustment circuit, including a fixed gain adjustment circuit which controls the waveform and level of an analog signal, wherein the analog signal is adjusted roughly in the fixed gain adjustment circuit and (the analog signal is adjusted) finely in the digital adjustment circuit thereby reducing the effect of the temperature characteristics and resolution the effect of the temperature characteristics and resolution and making it possible to carry out adjustment of convergence with high accuracy. A geomagnetism sensor circuit may also be provided for sensing changes in geomagnetism and outputting a signal for adjusting convergence to cancel out the effects of geomagnetism.

Abstract: In a convergence error detecting apparatus for use in combination with a display system of a projection type which displays, onto a display panel, a projected image signal which has a first synchronization signal of a predetermined frequency, and for detecting a convergence error signal representative of a convergence error appearing on the projected image signal, image pickup device is operated by a second synchronization signal of a frequency different from the predetermined frequency, for picking up the projected image signal to produce a pickup image signal by the use of the second synchronization signal, and processing unit processes the pickup image signal to detect the convergence error and to produce a convergence error signal representative of the convergence error. The convergence error signal is supplied to the display system to remove the convergence error in the display system.

Abstract: An apparatus for correcting images includes: a test signal generator for generating a test signal; a display device for displaying the test signal in a region on a display screen; an imaging device for imaging the test signal displayed on the display screen in a scanning direction so as to produce an image signal having a rising linear portion and a falling linear portion along the scanning direction; a position calculator for calculating a position of a centroid of the image signal for each of R, G and B colors, based on the rising linear portion and the falling linear portion; an error detector for detecting an amount of error between the detected positions of the centroids for R, G and B colors; a correction circuit for correcting a convergence and a geometric distortion for the region, based on the amount of error.

Abstract: A projection television apparatus has three monochromatic picture tubes disposed in a planar orientation defining a central picture tube and two outer picture tubes. Each of the picture tubes includes a deflection unit responsive to deflection currents and raster correction signals for vertical and horizontal deflection. A control circuit, including a signal generator, supplies vertical and horizontal raster correction signals formulated for the central picture tube to all three of the picture tubes and supplies additional vertical and horizontal raster correction signals formulated for the two outer picture tubes respectively to the two outer picture tubes, respectively. Conductive paths for the formulated for the central picture tube correction signals can include variable resistors for effecting small changes in signal amplitude.

Abstract: A wide aspect television receive corrects variations in the luminance between the center and peripheral portion of the screen that occur due to changing vertical deflection widths by suppressing a video signal amplitude at the top and/or bottom of the screen to be smaller than that at the center of the screen. The wide aspect deflection may also correct over-correction of the lateral pincushion distortion.

Abstract: A device for digital convergence correction of raster distortion correction of a picture displayed on a screen of a display device using a cathode-ray tube, in which scanning lines include a first class of scanning lines, called correction scanning lines, on which correction points are positioned, and a second class of scanning lines, called interpolated scanning lines between the correction scanning lines. The correction points are positioned at intersections of the correction scanning lines and vertical lines. The correction data for the interpolated scanning lines are produced by vertical interpolation from the correction data of a certain number of vertically aligned correction points. Convergence adjustment, however, may be conducted for only part of the correction points, and the correction data of the remaining correction points may be obtained by interpolation.

Abstract: In an automatic digital convergence correction method and apparatus therefore employing a CRT-type display, the vertical and horizontal convergence with respect to the red and green CRTs are tracked based on the ideal seed point within a test pattern generated via the green CRT so that the vertical and horizontal convergence match, to thereby enhance the accuracy of a correction operation and reduce the correction time.

Abstract: A convergence measurement apparatus for a color cathode-ray tube is capable of high precision convergence measurement by elimination of luminance omission portions occurring in the screen. A dot pattern displayed on a color cathode-ray tube is picked up by an image pickup camera and is stored in an image memory. A signal movement amount control unit is arranged to move a beam spot of the dot pattern displayed on the cathode-ray tube by a predetermined pitch in a horizontal or vertical direction. Corresponding dot pattern shifting occurs to sequentially record images of discrete colors for a more accurate measure of convergence. For example, if a gap between adjacent phosphor elements of one color (for example red) is defined as one pitch, three sequential red dot patterns can be each shifted by 1/3 of a pitch and thereafter picked up and stored in the image memory of dot pattern data.

Abstract: A convergence correction apparatus comprises: a scanning waveform generating section (6) for generating a scanning waveform in synchronization with a sync signal for scanning an electron beam in a cathode ray tube (8); an amplitude control section (7) for controlling a raster size according to a scanning waveform generated by the scanning waveform generating means (6) with receipt of a control signal; and a convergence correction waveform generating section (5) for generating a correction waveform for performing a convergence correction according to the scanning waveform and the control signal. Therefore, the apparatus can automatically follow signal sources having different input scanning frequencies and different aspect ratios thereby to obviate the need for complicated adjustment in each mode and remarkably reducing the time necessary for the adjustment.

Abstract: A dynamic focusing device for cathode ray tubes comprising a crosshatch pattern generator for providing a surface of cathode ray tubes with a crosshatch pattern indicating an adjustment point at which focusing control is carried out. The system uses correction data to achieve proper focus at each adjustment point, i.e., the intersection of the vertical and horizontal lines of the crosshatch pattern defined by arbitrarily divided blocks on the surface of the cathode ray tube. The data between adjacent adjustment points is interpolated in the vertical and horizontal directions to supply an output signal providing proper dynamic focus of the cathode ray tube. The disclosed device produces proper focus uniformity and is able to produce a high definition television image on direct-view devices or projection systems which utilize cathode ray tubes.

Abstract: To improve the sharpness of (video) pictures to be displayed on a display screen of a display device, it is known to use scan velocity modulation. The drawback of scan velocity modulation is that an improvement of the (impression of) sharpness is obtained in given types of video signal/pictures only. By starting from the properties of the display tube when improving the (impression of) sharpness of the displayed picture, a much better improvement can be obtained. Information about the relevant display tube is applied to a correction circuit which also receives a video signal-dependent signal. With reference to these input signals, the correction circuit determines whether and how the video signal is to be corrected so as to obtain an ideal picture on the display screen. Reducing the contrast is a first step of restoring the resolution. Modulating the read clock of the video signal is a second step. Using scan velocity modulation is the last step.

Abstract: A focus voltage control apparatus adapted for a color CRT and capable of achieving a just focused state of any desired color even in monochromatic display. Red, green and blue color signals R, G, B are integrated per horizontal line period in integrating/peak holding circuits and then are weighted respectively in weight control circuits. Subsequently the maximum one of the color signals is detected in a comparator, and one of color selection signals SR, SG, SB is outputted in accordance with the result of such detection and then is supplied to focus voltage converters for the individual colors. A reference focus voltage refV is converted into a color focus voltage VR, VG or VB on the basis of the color selection signal SR, SG or SB for just focusing the color signal R, G or B.

Abstract: A signal generating apparatus comprises: a scanning-line number detector (2) for detecting the number of scanning lines with receipt of a sync signal; a convergence memory (3) for storing convergence correction data; an on-screen display memory (5) for storing on-screen display data; an interpolator (4) for performing vertical interpolation of output data derived from the memories (3, 5) according to the detection signal derived from the scanning-line number detector (2); and a frame memory (6) for successively reading data elements corresponding to the individual scanning lines interpolated by the interpolator (4). The apparatus detects the number of scanning lines and generates a correction signal and a character signal through vertical processing of convergence correction data and on-screen character data.

Abstract: Methods and systems are presented in which at least one geometric distortion function is separately determined for application to a particular primary color component of a color video display to cause a geometric distortion that compensates for lateral chromatic aberration in an optical system used to view the display.

Abstract: An image correction apparatus uses digital correction data from a memory device, in which various correction data is stored, and various analog correction waveforms for implementing, through digital control, various correction, such as convergence, deflection, luminance, focus, frame phase, etc., to thereby accomplishing accurate and automatic correction.