KR970008569B1 - Miss conversions for electron gun - Google Patents

Abstract

In the misconvergence compensating apparatus including a vertical deflection coil for receiving constant voltage and generating a deflection magnetic field which deflects electron beam in a vertical direction, first and second vertical PCS compensation coils for generating the compensation magnetic field which precisely compensates the misconvergence of the vertical direct, and a horizontal PCS compensation coil for generating the compensation magnetic field which precisely compensates the misconvergence of the horizontal direction; the apparatus is provided by the characteristic that an amplifying element is connected to the second vertical PCS compensation coil in series, the amplifying element being for switching current applied to the second vertical PCS compensation coil and simultaneously amplifying current, whereby effectuating a complete compensation of a misconvergence of a reverse direction.

Description

Miss Convergence Corrector

1 is an exploded perspective view of a general deflection yoke,

2 is a screen state in which misconvergence occurs.

3 is a schematic circuit diagram of a conventional misconvergence correction device;

4 is a schematic circuit diagram of a misconvergence correction apparatus according to the present invention.

* Explanation of symbols for main parts of the drawings

1: deflection yoke 2: coil separator

3: horizontal deflection coil 4: vertical deflection coil

5: ferrite core 6: first vertical PS correction coil

7: second vertical PS correction coil 8, 9: diode for switch

10 horizontal horizontal correction coil 11, 12 amplification transistor

13,14: reverse current prevention diode

The present invention relates to a misconvergence correction device, and more particularly, a red (R) beam and a blue (B) at the center of the screen when the electron beam is deflected through a deflection yoke and scanned on the screen. The beams cross each other and are scanned, and the red (R) and blue (B) beams of the upper or lower part of the screen are scanned to cross each other so as to be opposite to the center part of the screen, that is, the reverse trillema (Trillema) In order to correct the voltage, the amplification transistor is configured to separately configure the first vertical PC (PCS) precision coil and the second vertical PS correction coil and amplify the amount of current applied to the second vertical PS correction coil. To the second vertical PS correction coil to enhance the strength of the correction magnetic field generated by the second vertical PS correction coil, Relates to a convergence correction device misses to be completely correct for convergence to miss.

Generally, the deflection yoke 1 as shown in FIG. 1 is mounted inside the coil separator 2 and the pair of coil separators 2 forming the outer structure of the deflection yoke 1, so as to level the electron beam. A pair of horizontal deflection coils 3 for generating a horizontal deflection magnetic field for deflecting in a direction, and a pair of vertical deflection coils mounted outside the coil separator 2 for generating a vertical deflection magnetic field for deflecting the electron beam in a vertical direction (4) and a magnetic body that is mounted to surround the vertical deflection coil 4 to reinforce the vertical deflection magnetic field generated in the vertical deflection coil 4, that is, the pair of ferrite cores 5 and the ferrite cores 5 are fixed thereto. It consists of a core clamp (not shown) that engages.

The deflection yoke (1) having such a structure is mounted on the cathode ray tube neck portion, and when a sawtooth pulse is applied to the horizontal deflection coil (3) and the vertical deflection coil (4), the magnetic field is generated by the Fleming's left-hand law. The emitted red (R), green (G), and blue (B) electron beams are deflected by a magnetic force to form a screen.

However, as described above, when the vertical deflection coil 4 is wound, the strength of the vertical deflection magnetic field generated in the vertical deflection coil 4 is different from each other on the upper and lower sides and the center of the screen due to the characteristics of the winding process. Occurred. In this case, as shown in FIG. 2, the red (R) beam is scanned more deflected than the blue (B) beam on the right side and the blue (B) beam is the red (R) beam on the right side. More deflected and scanned, blue (B) beams are deflected more than red (R) beams on the right side of the screen and red (R) beams are more than blue (B) beams on the left side Misconvergence that is deflected and scanned, i.e., an inverted trillema, is generated.

In order to correct the inversion trillama, a misconvergence correction apparatus as shown in FIG. 3 is conventionally used.

3 shows a pair of vertical deflection coils 4 connected in series, a first vertical PS correction coil 6 connected in series with the vertical deflection coils 4 for precise correction of vertical misconvergence, The second vertical PC is connected in parallel with the first vertical PS correction coil 6 and is wound in a direction opposite to the winding direction of the first vertical PS correction coil 6 to precisely correct the vertical misconvergence. A pair of switching diodes (8, 9) connected in series with the S correction coil (7) and the second vertical PS correction coil (7) for switching a current applied to the second vertical PS correction coil (7); Are connected in parallel to the first vertical PS correction coil 6 and the second vertical PS correction coil 7, respectively, and in series to a horizontal deflection coil (not shown in FIG. 3) to correct the first vertical PS correction coil. Applied from the coil 6 and the second vertical PS correction coil 7 It consists of a horizontal S. PC correction coil 10 to precisely compensate for the miss convergence in the horizontal direction by the system.

Here, reference numerals R1 to R2 are bias resistors for biasing the voltage applied to the vertical deflection coil 4, and VR is the voltage applied to the upper and lower vertical deflection coils 4 of the pair of vertical deflection coils 4. It is a variable resistor for controlling the amount. R3 is a damping resistor for adjusting the amount of current applied to the first vertical PS correction coil 6.

The operation of the conventional misconvergence correction apparatus configured as described above is as follows.

When the sawtooth voltage is applied from the terminal Y, at the voltage less than the switching voltage of the switching diodes 8 and 9 of the sawtooth voltages, the switching diodes 8 and 9 remain in the "off" state, and this voltage is vertically deflected. After applied to the coil 4 to generate a vertical deflection magnetic field, it is applied to the first vertical PS correction coil 6 through a damping resistor R3. The first vertical PS correction coil 6 receives a predetermined voltage from the vertical deflection coil 4 to generate a forward misconvergence correction magnetic field.

In addition, the predetermined current applied to the first vertical PS correction coil 6 is partially induced by the horizontal PS correction coil 10, and the horizontal PS correction coil 10 to which the predetermined current is applied is corrected in the horizontal misconvergence. Generate a magnetic field. Therefore, the misconvergence of the center portion of the screen is corrected by the composite magnetic field of the vertical misconvergence correction field in the forward direction and the misconvergence correction field in the horizontal direction.

On the other hand, since the switching diodes 8 and 9 are "turned on" at the voltage higher than the switching voltage of the switching diodes 8 and 9 among the sawtooth voltages applied from the terminal Y, this voltage is the vertical deflection coil 4. ) To generate a vertical deflection magnetic field, and then to the first vertical PS correction coil 6 and the second vertical PS correction coil 7 simultaneously. The first vertical PS correction coil 6 receives a predetermined voltage from the vertical deflection coil 4 to generate a forward misconvergence correction field, and the second vertical PS correction coil 7 is a vertical deflection coil 4. A predetermined voltage is applied to generate a reverse convergence correction field. Here, the magnitude of the misconvergence correction field generated by the second vertical PS correction coil 7 is greater than the magnitude of the misconvergence correction field generated by the first vertical PS correction coil 6, and thus, a combined magnetic field of the two correction magnetic fields. Is the reverse misconvergence correction field.

In addition, a predetermined current applied to the first vertical PS correction coil 6 and a predetermined current applied to the second vertical PS correction coil 7 are partially induced in the horizontal PS correction coil 10, and a predetermined current is applied. The horizontal PC correction coil 10 applied with generates a misconvergence correction magnetic field in the horizontal direction. Therefore, the misconvergence generated on the upper and lower sides of the screen in the opposite direction to the misconvergence generated at the center portion of the screen is partially corrected by the composite magnetic field of the reverse vertical misconvergence correction field and the horizontal misconvergence correction field.

However, in the above case, the amount of current applied to the second vertical PS correction coil is greatly reduced by the switching diode, so that the second vertical PS correction coil does not generate a sufficiently large misconvergence correction magnetic field. Therefore, the magnetic field generated in the first vertical PS correction coil and the magnetic field generated in the second vertical PS correction coil cancel each other, so that the misconvergence generated in the center portion of the screen is corrected, but the miss occurs in the upper and lower sides of the screen. There was a problem that convergence could not be fully corrected.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to mount an amplification element so as to amplify the amount of current applied to the second vertical PS correction coil. The present invention provides a misconvergence correction device capable of completely correcting the misconvergence generated on the upper and lower sides of a screen by generating a misconvergence correction magnetic field.

A feature of the misconvergence correction apparatus according to the present invention for achieving the above object is a vertical deflection coil for generating a deflection magnetic field for deflecting the electron beam in the vertical direction by applying a predetermined voltage, and precisely the vertical misconvergence in the vertical direction. A deflection yoke having first and second vertical PS correction coils for generating a misconvergence correction field for correction and a horizontal PS correction coil for generating a misconvergence correction field for precise correction of horizontal misconvergence. A misconvergence correction device, comprising: The amplification element for switching the current applied to the second vertical PS correction coil and amplifying the current is connected in series with the second vertical PS correction coil.

Hereinafter, a preferred embodiment of the misconvergence correction apparatus according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 4 is a schematic circuit diagram of the misconvergence correction apparatus according to the present invention. In FIG. 4, the same reference numerals as those of FIG. 3 denote the same parts, and thus the description thereof is omitted, and only essential components of the present invention are omitted. Explain.

4, the switching diodes 8 and 9 are removed from the components in FIG. 3, and the amplifying transistors 11 and 12 are mounted on the left and right sides of the second vertical PS correction coil 7, respectively. Reverse voltage prevention diodes 13 and 14 were mounted on the amplifying transistors 11 and 12, respectively.

Here, reference numerals R4 to R7 are bias resistors.

The operation of the misconvergence correction apparatus according to the present invention configured as described above is as follows.

First, when a sawtooth wave voltage is applied from the terminal Y, the voltage is applied to the base of the amplifying transistors 11 and 12 through the bias resistors R4 and R7. At voltages below the switching voltage, the amplifying transistors 11 and 12 remain in the " off " state, so that this voltage is applied to the vertical deflection coil 4 to generate a vertical deflection magnetic field, and then through the damping resistor R3. Is applied to the first vertical PS correction coil 6. The first vertical PS correction coil 6 receives a predetermined strain from the vertical deflection coil 4 to generate a forward misconvergence correction magnetic field. In addition, the predetermined current applied to the first vertical PS correction coil 6 is partially induced by the horizontal PS correction coil 10, and the horizontal PS correction coil 10 to which the predetermined current is applied is corrected in the horizontal misconvergence. Generate a magnetic field. Therefore, the misconvergence of the center portion of the screen is corrected by the composite magnetic field of the vertical misconvergence correction field in the forward direction and the misconvergence correction field in the horizontal direction.

On the other hand, at a voltage equal to or greater than the switching voltage of the amplifying transistors 11 and 12 among the sawtooth voltages applied from the terminal Y, the applied voltage is the base of the amplifying transistors 11 and 12 through the bias resistors R4 and R7. Is applied to the amplifying transistors 11 and 12 to " turn on " and the amplifying transistors 11 and 12 are " turned on " Is generated and applied simultaneously to the first vertical PS correction coil 6 and the second vertical PS correction coil 7. The first vertical PS correction coil 6 receives a predetermined voltage from the vertical deflection coil 4 to generate a forward misconvergence correction field, and the second vertical PS correction coil 7 is a vertical deflection coil 4. The feedback voltage and the amplification operation are applied to generate an inverse misconvergence correction field which is much larger than the forward misconvergence correction field generated by the first vertical PS correction coil 6. Here, since the magnitude of the misconvergence correction field generated in the second vertical PS correction coil 7 is larger than the magnitude of the misconvergence correction field generated in the first vertical PS correction coil 6, the synthesis of the two correction fields is performed. The magnetic field is a reverse misconvergence correction magnetic field.

In addition, a predetermined current applied to the first vertical PS correction coil 6 and a predetermined current applied to the second vertical PS correction coil 7 are partially induced in the horizontal PS correction coil 10, and a predetermined current is applied. The horizontal PC correction coil 10 applied with generates a misconvergence correction magnetic field in the horizontal direction. Therefore, the misconvergence generated on the upper and lower sides of the screen in the opposite direction to the misconvergence generated at the center portion of the screen is completely corrected by the composite magnetic field of the reverse vertical misconvergence correction field and the horizontal misconvergence correction field.

As described above, according to the misconvergence correction apparatus according to the present invention, the amplification element for switching and simultaneously amplifying the amount of current applied to the second vertical PS correction coil is connected in series with the second vertical PS correction coil, The vertical PS correction coil generates a reverse misconvergence that is much larger than the magnitude of the forward misconvergence correction field generated by the first vertical PS correction coil, thereby completely correcting the reverse misconvergence generated on the upper and lower sides of the screen. It can work.

Claims (1)

Vertical deflection coils for generating a deflection magnetic field for deflecting the electron beam in the vertical direction by applying a predetermined voltage, and first and second vertical PS correction coils for generating misconvergence correction fields for precise correction of vertical misconvergence. And a horizontal yoke correction coil for generating a misconvergence correction magnetic field for precisely correcting the horizontal misconvergence; And an amplifying element connected in series to a second vertical PS correction coil, while switching a current applied to the second vertical PS correction coil and amplifying the current.