KR920004399Y1 - Deflection yoke picture compensating device - Google Patents

Abstract

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Description

Deflection yoke image correction device

1 is a circuit diagram showing an image correction apparatus of the present invention.

2 is a waveform diagram of voltage and current, (a) is a sawtooth waveform diagram output from a vertical deflection circuit of a cathode ray tube, (b) is a parabolic current waveform diagram flowing through a correction coil of the present invention, (c) and (d ) Is a current waveform diagram output from the adjustment terminal of the present invention.

3 is a diagram illustrating the convergence, (a) is an explanatory diagram showing the misconvergence output from the deflection yoke, (b), (c) is an explanatory diagram showing the mis convergence V-shifted by the deflection yoke axis error.

* Explanation of symbols for main parts of the drawings

Lv: Vertical Deflection Coil Iv: Vertical Deflection Current

Ic: correction current R1: attenuation resistance

R2: Auxiliary resistor VR1, VR2, VR3: Variable resistor

Lc: Correction coil D1, D2, D3, D4: Diode

The present invention relates to a deflection yoke image correcting apparatus, and more particularly, a trajectory of an electron beam deflected by a deflection yoke attached to a vertical deflection circuit of an inline type self-convergence deflection yoke mounted on a cathode ray tube of a television receiver. The present invention relates to an image preservation apparatus that exactly matches one point of a screen.

The deflection yoke is mounted on the front of the neck of the cathode ray tube and finally deflects the beam generated from the electron gun on the screen. The main structure is a vertical coil that deflects the beam's vertical component outside the trumpet-shaped separator. It is attached, and the inner side is comprised by attaching the horizontal coil which deflects the left-right component of a beam.

At this time, the vertical and horizontal coils generate a magnetic field on the path of the beam by energization so that the beam scanned is distorted.

In particular, in a color television receiver, when the three electron beams simultaneously touch the corresponding fluorescent dots through any one of the holes on the shadow mask, the images of the three colors harmonize correctly to form a normal image. When not in color.

This color deviation may occur in the entire screen or only in a part of the periphery of the screen (for example, the upper end or the left end of the screen). In the former case, the correlation of the three electron beams in the radial direction is not correct. In this case, it is necessary to correct the directions of the three electron beams separately. In other words, three electron beams at any moment concentrate through the holes of the specified shadow mask so that they can accurately reach the three-color fluorescent elements (dots). This is equivalent to three types of bullets hitting three targets each defined through the same hole, and focusing on the hole of the shadow mask is called convergence in the present invention.

At this time, in order to correct the directions of the three electron beams separately, a magnet (positive-conductance magnet) capable of changing the direction and intensity of the magnetic field in the neck of the water pipe and a current of a special waveform synchronized with the deflection current Horizontal and vertical coils (copper convergence coils) should be installed.

As an example of such a device, in the conventional inline type self-convergence deflection yoke, the deflection magnetic field is configured as the failed magnetic field and the vertical deflection coil as the magnetic field. In order to obtain, there is a drawback that it is difficult to obtain a satisfactory convergence characteristic only with the conventional self-convergence magnetic field.

As a solution to the above-described drawbacks, Japanese Patent Application Laid-Open No. 58-212039, Japanese Patent Application Laid-Open No. 61-16448, Japanese Patent Application Laid-Open No. 61-142887, Japanese Patent Application Publication 61 as a proposal using an auxiliary coil to improve convergence characteristics. -158653.

The means disclosed in the above-mentioned Japanese Laid-Open Patent Publications are as follows. In other words, the auxiliary coil is used for the deflection yoke, and the vertical deflection magnetic field and the convergence voltage are designed in the optimal state, and the correction current obtained by full-wave rectification of the vertical deflection current is applied to the correction coil to correct the residual misconvergence. It is supposed to be.

However, the above-described image correction apparatus of the prior art cannot correct the V-shift, which is the convergence error caused by the eccentricity of the CRT gun or the axial error of the deflection coils (vertical and horizontal coils), and also the upper and lower misconvergence. There is a drawback that cannot be adjusted separately.

The present invention has been devised to solve the above-mentioned drawbacks of the prior art, by minimizing the X-axis deflection magnetic field by installing a horizontal coil for failing magnetic field generation in the deflection yoke, and by installing the annular magnetic field generating vertical coil. Misconvergence by adjustment, that is, the B beam relative to the R beam of the vertical center line on the Y axis is adjusted to the minimum at a point other than the misconvergence in the horizontal direction, and the misconvergence is separately compensated, and the CRT and deflection yoke matching It aims to correct V-shift components generated by eccentricity of electron gun and axial error of deflection yoke.

In order to achieve the above object, the present invention provides an image correction circuit in which two variable resistors are interpolated as an adjustment terminal for misconvergence adjustment, and at the same time, one variable resistor for the V-shift adjustment terminal is interpolated.

Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings.

In the image correction apparatus of the present invention, as shown in FIG. 1, the vertical deflection coil Lv is connected to the vertical deflection circuit, and the auxiliary resistor R2 is connected in series to ground.

In addition, the attenuation resistor R1 is connected in parallel to the vertical deflection coil Lv, and the variable resistor VR1 and the variable resistor VR2 are connected in parallel with the auxiliary resistor R2 to ground.

The diode D1, the correction coil Lc, and the diode D4 are connected in the forward direction based on the variable point of the variable resistor VR1 to ground.

In addition, the diode D2 connects the correction coil Lc and the diode D3 in the reverse direction on the basis of the variable point of the variable resistor VR2, and the correction coil Lc is disposed in the middle of the diodes D1, D2, and D3. ) And the variable point (VR3) for the V-shift adjustment terminal in parallel to ground the variable point.

The description of the operation of the image correcting apparatus of the present invention having such a configuration will be described with reference to FIGS.

2 is a waveform diagram of voltage and current, (a) is a top waveform diagram output from a vertical deflection circuit, and (b) is a parovola type current waveform diagram output from a correction coil Lc, (c), (d ) Is the correction current that outputs from the adjustment terminal and corrects the V-shift.

3 shows convergence, in which (a) is a horizontal misconvergence of the R beam and the B beam in the vertical line of the Y axis, and (b) is a non-convergence in which the R bin and the B beam intersect. (C) is a misconvergence in which the R beam and the B beam intersect, that is, the electron beam is deviated downward.

4 is an exemplary diagram of adjusting misconvergence, (a) is misconvergence, (b) is adjusting upper and lower misconvergence using variable resistors VR1 and VR2, and (c) is misconvergence. The electron beam to be adjusted is coincident.

In FIG. 1, the vertical deflection current from the vertical deflection circuit is applied to the vertical deflection coil Lv outputted in the same waveform as that of FIG. 2A.

When the vertical deflection current applied to the vertical deflection coil Lv is positive (+) on the sawtooth wave of FIG. 2A, the diode D1 and the correction coil Lc through the variable point of the misconvergence upper adjustment variable resistor VR1. And sequentially flow through the diode D4.

At this time, the current waveform flowing through the correction coil Lc is as shown in the first half of FIG. 2B. When the current amount is added or subtracted by the variable resistor VR1, the magnetic field of the correction coil Lc is changed and the degree of deflection of the electron beam is changed. Therefore, the upper part of the misconvergence (Fig. 4A) is corrected as the right side of Fig. 4B.

Subsequently, when the vertical deflection current is negative in FIG. 2A, the current is variable through the diode D3, the correction coil Lc, and the diode D2. The point flows.

At this time, the current wave flowing through the correction coil Lc is as shown in the second half of FIG. 2B. When the current amount is added to or subtracted from the variable resistor VR2, the magnetic field of the correction coil Lc is changed and the degree of deflection of the electron beam accordingly. Since the lower part of the misconvergence (Fig. 4A) is corrected as shown in the left side of Fig. 4B.

Accordingly, when the convergence of the upper and lower parts is corrected as described above, the R beam and the B beam are matched as shown in FIG. 4C.

As described above, the vertical deflection current appears through the correction coil Lc as the second b degree because the vertical deflection current is rectified as a parabolic (parabola) correction current due to the operation characteristics of the actual diode.

In addition, in order to adjust the V-shift, a correction current (2c, d degrees) is required according to each pattern of misconvergence, which is possible by adjusting the variable resistor VR3.

More specifically, when the electron beam is displaced upward (Fig. 3b), the potential difference across the diodes D3 and D4 is changed to generate a V-shift correction current (Fig. 3c) to correct the V-shift and to lower the electron beam. In the case of deviation (Fig. 3C), the variable resistor VR3 is changed to generate the correction current of Fig. 2D to correct the V-shift.

When the image correction apparatus of the present invention which performs the above operation is mounted on the deflection yoke, the design of the deflection yoke can be freely set, and a high-quality image can be obtained over the entire screen.

In addition to correcting the misconvergence of the deflection yoke, it is also possible to correct misconvergence and V-shift due to CRT eccentricity or deflection yoke axial error, and also to dynamically adjust the misconvergence due to CRT dispersion and deflection yoke dispersion. There is an advantage in improving mass productivity and improving remarkable products.

Claims (1)

The vertical deflection coil Lv and the auxiliary resistor R2 are connected in series with the vertical deflection circuit, the attenuation resistor R1 is connected in parallel with the vertical deflection coil Lv, and the variable resistance VR1 for the misconvergence upper current amount change. And a variable resistance VR2 for changing the lower current amount of the misconvergence lower current in parallel with the auxiliary resistor R2, and the diode D1, the correction coil Lc, and the diode D4 from the variable point of the variable resistor VR1. ) Is connected in series, and the diode D2, the correction coil Lc, and the diode D3 are connected in the reverse direction from the variable point of the variable resistor VR2, and are deflected in parallel with the correction coil Lc. A deflection yoke image correcting device characterized by connecting a variable resistor (VR3) for adjusting the V-shift due to a yoke axis error.