JPH10149783A - Convergence compensator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a convergence compensator which enables to separately compensate a vertical line mis-convergence of the upper and lower areas of a screen. SOLUTION: When vertically deflecting the upper area of a screen, a vertical deflecting current I input to a terminal A passing through vertical defection coils VL1 and VL2S is diverted to I1 and I2 by a variable resistor VR1, and then returns to the vertical deflection circuit from B point through convergence compensation coil L1 and L2, and L3 and L4 respectively. When vertically deflecting the lower area of screen, a vertical deflecting current I input to B point from vertical deflection circuit is diverted to I1 and I2 passing through L1 and L2, and L3 and L4, and then returned to the vertical deflection circuit by the variable resistor VR2. Next, as for diverted currents I3 and I4 not depending on the vertical deflection current I, A point is connected to a variable terminal by connecting one end of L1 and L2, and L3 and L4 to a fixed resistance terminal of a variable resistor VR3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a deflection yoke which is used by being attached to an in-line color cathode ray tube.
In particular, the present invention relates to a convergence correction device for correcting misconvergence of a vertical line generated at the top and bottom of a screen.

[0002]

2. Description of the Related Art FIG. 6 is a diagram showing an example of a conventional vertical line misconvergence, and FIG. 7 is a circuit diagram of the convergence correction device. In a CRT using in-line arranged beams, misconvergence of vertical lines as shown in FIG. Here, a solid line passing through the center of the screen is a B (blue) vertical line, and a broken line passing through the center of the screen is an R (red) vertical line. This is caused by a positional shift between the R beam and the B beam at the top and bottom of the screen, and deteriorates the image quality.

FIG. 7 shows a conventional example of a convergence correction device for correcting such vertical line misconvergence. The first diode D1, the variable resistor VR1, and the upper side correction coils L1 and L2 are connected in series.
For correcting a bow-shaped misconvergence of a vertical line on the upper and lower sides of the screen by connecting in parallel a second diode D2, a variable resistor VR2, and a lower side correction coil L3, L4 connected in series in the opposite direction to the diode D1. And two correction coils L
5, L6, two impedance elements R and a variable resistor VR
3 in parallel and a variable resistance terminal and two correction coils L
A correction device for correcting the cross-shaped misconvergence of the vertical line connecting the connection points 5 and L6 is connected in series, and this is connected in series to the vertical deflection coils VL1 and VL2.

With this configuration, when the upper half is vertically deflected, the first diode D1 is turned on, a current flows through the upper side correction coils L1 and L2, and when the lower half is vertically deflected, the second diode D1 is turned on. When the diode D2 conducts and a current flows through the lower side correction coils L3 and L4, the vertical misalignment of the vertical line at the top and bottom of the screen is corrected independently by adjusting the respective variable resistors VR1 and VR2. . Next, the cross-shaped misconvergence of the vertical line was performed by adjusting the variable resistor VR3.

[0005]

However, in the above-mentioned prior art, the vertical arcuate misconvergence generated in the upper part and the lower part of the CRT can be corrected independently of each other.
The correction direction of the beam and the B beam is one direction. In the case of the opposite direction, it is necessary to connect the correction coil in reverse or reverse the direction of the current.

The conventional vertical line cross-shaped misconvergence correction device requires a coil having a function of vertical line black-shaped misconvergence correction in addition to the vertical line arc-shaped misconvergence correction coil. Further, when performing cross-shaped misconvergence correction of vertical lines, the G beam also has a problem of moving.

Therefore, the present invention solves such a problem and reduces the CR.
It has both the function of adjusting the R and B beams only in both the left and right directions, and the function of correcting the vertical line cross-shaped misconvergence, independently of the vertical line bow-like convergence that occurs in the upper half and lower half of the T screen. It is an object of the present invention to provide a convergence correction device.

[0008]

According to a first aspect of the present invention, there is provided a convergence yoke drive circuit and a convergence correction coil provided for each of a plurality of magnetic bodies, wherein the convergence yoke drive circuit is connected to a vertical coil. At least one pair of oppositely connected diodes connected in parallel with each other and a variable resistor connected to each diode and shunting a vertical deflection current flowing through a vertical deflection coil to each convergence correction coil. Is divided into a current flowing through a diode and a variable resistor that differs depending on the flowing direction, and a current flowing through a variable resistor in a path independent of the flowing direction, and the vertical deflection current flows through each convergence correction coil, Independent misconvergence that occurs at the top and bottom of the screen by adjusting the variable resistance It was so positive to.

According to the second aspect of the present invention, it is possible to create a state in which convergence correction is not performed by adjusting each of the variable resistors to a neutral position.

According to a third aspect of the present invention, two sets of the convergence correction coils are provided in the vertical direction, and two sets of the convergence correction coils are provided for each of the magnetic substances, one set being an upper and a lower set. The generated magnetic field has a canceling action.

According to a fourth aspect of the present invention, the magnetic material comprises a pair of upper and lower coils arranged in series in a vertical direction and connected in series, and the convergence correction coil includes two sets of coils. By providing it for each body, the coil can be easily assembled after it is created independently.

According to a fifth aspect of the present invention, the convergence correction coil is composed of two sets of left and right coils arranged in series in the horizontal direction and connected in series. With the provision, the coil can be easily assembled after being made independently.

According to a sixth aspect of the present invention, the two convergence correction coils are arranged such that a magnetic field is generated in a direction in which currents in the same direction cancel each other.

According to a seventh aspect of the present invention, the magnetic field generated by the convergence yoke does not affect the G (green) beam at the center of the CRT using the in-line arranged beams.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 has a function of independently correcting a vertical arcuate misconvergence of a vertical line generated at an upper portion and a lower portion of a screen by adjusting each variable resistance. Cross-like convergence can be corrected.

According to a second aspect of the present invention, a state in which convergence correction is not performed can be created by adjusting each of the variable resistors to a neutral position. The bare characteristics of the coil can be confirmed.

According to a third aspect of the present invention, in the first or second aspect, the magnetic body is arranged in a set in a vertical direction, and the convergence correction coil is provided for each of the magnetic bodies, and a pair of upper and lower convergence correction coils is provided. Two sets are provided, and two sets
The magnetic fields generated by the set of convergence correction coils have a canceling action.

According to a fourth aspect of the present invention, in the first or second aspect, the magnetic material comprises a pair of two upper coils and one lower coil which are arranged in a vertical direction and connected in series. By providing the convergence correction coil composed of a set of coils for each magnetic body, it is possible to easily incorporate the coil after creating the coil alone.

According to a fifth aspect of the present invention, in the first or second aspect, the magnetic body is a pair of left and right coils arranged in series in a horizontal direction and connected in series. By providing the convergence correction coil for each magnetic body, it is possible to easily incorporate the coil after creating the coil alone.

According to a sixth aspect of the present invention, the two sets of convergence correction coils are arranged so that magnetic fluxes are generated in directions canceling each other by currents in the same direction, thereby adjusting the current values of the two sets of convergence correction coils. Has the function of changing the direction of the magnetic field generated.

According to a seventh aspect of the present invention, in the first aspect, the magnetic field generated by the convergence yoke does not affect the G (green) beam located at the center of the CRT using the in-line arranged beams. , Which do not affect the VCR characteristics.

(Embodiment 1) FIG. 1 is a circuit diagram of a convergence correction device according to Embodiment 1 of the present invention, FIG. 2 is an explanatory diagram of the convergence yoke, FIG. 3 is an explanatory diagram of the convergence yoke, and FIG. FIG. 4 is an explanatory view of the convergence yoke. In FIG. 1, 1 is a convergence drive circuit, VL1 and VL2 are vertical deflection coils, D1 and D2 are diodes, VR1, VR2, and VR3 are variable resistors, L1 and
L2, L3, L4 are convergence correction coils, A, B
Is a terminal, P is a connection point, R1 is a fixed resistor, I is a vertical deflection current, and I1, I2, I3, and I4 are partial currents.

The terminals A and B are connected to a vertical deflection circuit (not shown). Vertical deflection coils VL1 and VL2 are connected in series between one terminal A and a connection point P. Variable resistors VR1, VR2, V
Each fixed resistance terminal of R3 is connected in parallel, one end of convergence correction coils L1 and L2 connected in series to each fixed resistance terminal, and one end of convergence correction coils L3 and L4 connected in series. . One terminals of the convergence correction coils L2 and L4 are connected to the terminal B, respectively.

A diode D1 between the sliding terminal of the variable resistor VR1 and the connection point P, which becomes forward when viewed from the connection point P side.
However, between the sliding terminal of the variable resistor VR2 and the connection point P, there is provided a diode D2 which is in the opposite direction as viewed from the connection point P, and the sliding terminal of the variable resistor VR3 is connected to a fixed resistor R1. Terminals are connected to the connection points P, respectively. In such a configuration, a vertical deflection current I is supplied between the terminals A and B from the vertical deflection circuit.

The vertical deflection current I flows in the case where the upper half area of the CRT screen is vertically deflected and the case where the lower half area of the CRT screen is vertically deflected. When vertical deflection occurs, for example, when the current flows from the terminal A to the terminal B, the vertical deflection current I flows from the terminal B to the terminal A when the lower half area of the CRT screen is vertically deflected.

Now, assuming that the vertical deflection current I flows from the terminal A, the vertical deflection current I passes through the vertical deflection coils VL1 and VL2 and from the connection point P to the variable resistor VR1 via the diode D1 which is now in the forward direction. And the current I
1, I2. The current that does not depend on the direction is separated into the divided currents I3 and I4 by the variable resistor VR3. These component currents I1, I2, I3, and I4 flow through the convergence correction coils L1, L2, L3, and L4, respectively, and return from the terminal B to the vertical deflection circuit.

In the vertical line misconvergence, the cross-shaped misconvergence is adjusted by adjusting the variable resistor VR3 to obtain the divided current I.
The optimization is performed by optimizing the ratio of I.3 and I.sub.4, and the arcuate misconvergence of the vertical line at the top of the screen is adjusted by adjusting VR1 to optimize the ratio of the divided currents I1 and I2. When the vertical deflection current I flows from the terminal B, the vertical deflection current I is applied to the convergence correction coils L1, L2, L3,
The current is shunted to L4 and combined by the variable resistors VR2 and VR3.

These convergence correction coils L1, L
2, the ratio of the currents flowing through L3 and L4 is optimized by adjusting the variable resistors VR2 and VR3. Variable resistance V
Part of the vertical deflection current synthesized by R2 passes through the diode D2 which is now in the forward direction, while the variable resistance VR3
And the vertical deflection coils VL1 and VLL together with the current
2 and return to the vertical deflection circuit.

In the vertical line misconvergence, the cross-shaped misconvergence is adjusted by adjusting the variable resistor VR3 and dividing the current I.
3 and I4 are optimized, and the vertical arcuate misconvergence at the top of the screen is adjusted by adjusting VR2 to optimize the ratio of the divided currents I1 and I2.

By adjusting the variable resistor VR3 in this manner, it is possible to correct vertical cross-shaped misconvergence. The convergence correction is performed between when the upper half of the CRT screen is vertically deflected and when the lower half is vertically deflected. The ratio of the currents flowing through the coils L1, L2, L3, L4 can be independently optimized using the variable resistors VR1, VR2.

Next, a specific example and operation of the convergence yoke will be described with reference to FIGS. In the figure, 2 is a convergence yoke, and M1 and M2 are magnetic materials. FIG.
(A) shows a first specific example of the convergence yoke 2. The pair of magnetic bodies M1 and M2 is C (not shown).
The convergence correction coils L1 and L3 are provided on the magnetic material M1 and the convergence correction coils L2 and L4 are provided on the magnetic material M2, and the convergence yoke 2 is provided. These convergence correction coils L1, L2, L3, L4
The currents I1, I2, and I1, as described with reference to FIG.
3 and I4 are energized, and a convergence correction magnetic field B1 is generated by the convergence correction coils L1 and L2, and a convergence correction magnetic field B2 is generated by the convergence correction coils L3 and L4, as shown in FIG. The correction magnetic fields B1 and B2 are connected such that the polarities are generated in opposite directions. The G (green) beam is located at the center of the R beam and the B beam, and the effects of the convergence correction magnetic fields B1 and B2 cancel each other. The R beam and the B beam pass through the portions on both sides in the horizontal direction of the G beam. Therefore, the convergence correction magnetic field B1,
It acts on the R and B beams of the magnetic field of B3 generated by the strength of B2. As shown in FIGS. 2B and 2C, the directions of the electromagnetic forces F3R and F3B by the convergence correction magnetic field B3 are opposite to each other with respect to the vertical axis.

Therefore, the electromagnetic force acting on the R beam and the B beam can be adjusted in a direction toward or away from each other, depending on the direction of the magnetic field of B3. The arcuate misconvergence at the top and bottom of the screen is controlled by a variable resistor V
By adjusting R1 and VR2 to adjust the ratio of the divided currents I1 and I2 to the optimum value, the R beam can be shifted independently to the right and the B beam to the left independently according to the situation of misconvergence. It is possible to correct the R beam to the left and the B beam to the right.

Next, the operation for correcting the vertical cross-shaped misconvergence will be described. In FIG. 1, the current that is not affected by the direction of the vertical deflection current becomes the divided currents I3 and I4 by the variable resistor VR3. In FIG. 4, the magnetic field generated by the divided current I3 and the convergence correction coils L1 and L2 is denoted by B4, and the magnetic field generated by the divided current I4 and the convergence correction coils L3 and L4 is denoted by B5. Therefore, as shown in FIG. 6C, when a cross-shaped misconvergence occurs in the upper half of the screen where the B beam is on the right side and the R beam is on the left side, the upper part of the screen is adjusted by adjusting the variable resistor VR3 so that I3> I4. When the beam is vertically deflected, B4> B5, and electromagnetic forces F6B and F6R acting on the B beam to the left and the R beam to the right are generated as shown in FIGS. 4 (a) and 4 (c).

Next, when the lower side of the drawing is vertically deflected, the direction of the current is reversed, but the ratio of the divided currents is adjusted so that I3> I4, so that the magnitude of the electromagnetic forces B4 and B5 is B4>
B5 becomes the acting direction. Therefore, the directions of the electromagnetic forces F6B and F6R acting on the B and R beams are as shown in FIG.
As shown in (b) and (d), generation of electromagnetic forces F6B and F6R acting on the B beam in the right direction and the R beam on the left direction enables correction of vertical cross-shaped misconvergence.

Next, as shown in FIG. 6D, in the correction of the cross misconvergence of the vertical line with the left side of the B beam and the right side of the R beam at the upper part of the screen, the current which is not influenced by the direction of the vertical deflection current is the variable resistor VR3. By adjusting the divided currents I3 and I4 so as to satisfy I3 <I4, when the upper part of the screen is vertically deflected, B4 <B5, and the B beam is shifted to the right.
An electromagnetic force acts on the beam to the left. Next, when the lower side of the screen is vertically deflected, the direction of the current is reversed, but the ratio of the divided current is adjusted so as to satisfy I3 <I4, so that the magnitudes of the electromagnetic forces B3 and B4 become B3 <B4. The directions are reversed. Therefore, as for the direction of the electromagnetic force acting on the B and R beams, the electromagnetic force acting on the B beam to the left and the R beam to the right acts to correct vertical cross-shaped misconvergence.

Incidentally, the variable resistors VR1, VR2, VR3 for adjusting the divided current are shown in the circuit diagrams of FIGS. 2 and 5 (described later).
Are adjusted to the state of the middle point respectively, so that the correction magnetic fields B1, B
2. The directions are opposite to each other with the same strength. The correction magnetic fields B4 and B5 also have the same strength and opposite directions.
Therefore, by acting in directions that cancel each other, it is possible to generate a state excluding the function of convergence correction by the correction coil. Therefore, it is easy to check the nakedness characteristics of the vertical deflection coil, and it is possible to manage the nakedness characteristics of the vertical deflection coil in the production process, which is an important function for stabilizing the characteristics.

(Embodiment 2) FIG. 5 is a circuit diagram of a convergence correction device according to Embodiment 2 of the present invention, wherein convergence correction coils L1, L2, L3 and L4 are shown in FIG.
L1 is set to L so that it can be mounted on the left and right sides of the magnetic bodies M1 and M2 in (b) and above and below the magnetic bodies M1 and M2 in FIG.
11 and L12, L2 to L21 and L22, L3 to L3
1 and L32, and L4 is separated into L41 and L42, respectively, so that mounting is easy.

[0038]

As described above, according to the present invention, irrespective of the misconvergence of a vertical arc formed at the upper part and the lower part on the CRT screen, and even if the misconvergence is different,
Each can be sufficiently corrected. In addition, the correction of vertical cross-shaped misconvergence can be sufficiently corrected by using a correction coil.

Further, according to the present invention, it is possible to create a state in which convergence correction is not performed by adjusting each of the variable resistors to the neutral position, and it is possible to confirm the nakedness characteristics of the vertical deflection coil, and it is possible to check the quality of the vertical deflection coil. It is sufficiently effective for improvement.

Further, by dividing the convergence correction coil into two parts and providing the convergence correction coil on the magnetic body, the convergence correction coil can be mounted after being wound, thereby simplifying the manufacture of the convergence yoke.

[Brief description of the drawings]

FIG. 1 is a circuit diagram of a convergence correction device according to a first embodiment of the present invention.

FIG. 2 is an explanatory diagram of a convergence yoke of the convergence correction device according to the first embodiment of the present invention.

FIG. 3 is an explanatory diagram of a convergence yoke of the convergence correction device according to the first embodiment of the present invention.

FIG. 4 is an explanatory diagram of a convergence yoke of the convergence correction device according to the first embodiment of the present invention.

FIG. 5 is a circuit diagram of a convergence correction device according to a second embodiment of the present invention.

FIG. 6 shows an example of a conventional vertical line misconvergence.

FIG. 7 is a circuit diagram of a conventional convergence correction device.

[Explanation of symbols]

 1 Convergence yoke drive circuit 2 Convergence yoke VL1, VL2 Vertical deflection coil D1, D2 Diode

Claims (7)

[Claims] 1. A convergence correction device attached to a color cathode ray tube using multiple electron beams in an in-line arrangement, comprising a convergence yoke drive circuit and a convergence correction coil provided for each of a plurality of magnetic bodies. The yoke drive circuit includes at least a pair of oppositely connected diodes connected in parallel in opposite directions connected to the vertical coil, and a variable shunt current flowing through the vertical deflection coil connected to each diode to each convergence correction coil. And the vertical deflection current is divided into a current flowing through a variable diode and a variable resistor depending on a flowing direction thereof, and a current flowing through a variable resistor on a path independent of the flowing direction. Flows into each convergence correction coil, and each variable resistance Convergence correction apparatus characterized by correcting the misconvergence occurring at the top and bottom of the screen by adjusting independently. 2. The convergence correction device according to claim 1, wherein a state in which convergence correction is not performed can be created by adjusting each of the variable resistors to a neutral position. 3. The magnetic body is arranged in a set in a vertical direction,
The convergence correction device according to claim 1, wherein two sets of the convergence correction coils are provided for each of the magnetic bodies, one set being an upper and a lower set, and the magnetic field generated by the two sets of convergence correction coils has a function of canceling each other. . 4. The convergence correction coil comprising two sets of coils, each pair of a pair of upper and lower coils arranged in series in the vertical direction and arranged in a vertical direction, for each of the magnetic bodies. 3. The convergence correction device according to claim 1, wherein the coil is independently formed and then incorporated. 5. The magnetic material according to claim 1, wherein said magnetic material comprises two sets of left and right convergence correction coils which are arranged in a horizontal direction and connected in series, and each of which has two coils. 3. The convergence correction device according to claim 1, wherein the convergence correction device is incorporated after being created independently. 6. The two sets of convergence correction coils,
6. The convergence correction apparatus according to claim 1, wherein magnetic fields are generated in directions in which currents in the same direction cancel each other. 7. The convergence correction apparatus according to claim 1, wherein the magnetic field generated by the convergence yoke does not affect a G (green) beam at a center position of the CRT using the in-line arranged beams.