JPH04261292A - Convergence device for in-line type color picture tube - Google Patents

Abstract

PURPOSE:To correct horizontal mis-convergence of a pattern intermediate part independently by supplying a current modulated synchronously with a half the vertical deflection period to a coil correcting the horizontal mis-convergence of the pattern intermediate part. CONSTITUTION:A current waveform modulation coil section 45 consists of a coil connecting to a horizontal deflection synchronization correction circuit section 42 and a coil connecting to a capacitor 54 of a vertical deflection synchronization correction circuit section 44. Then a current of a nearly parabolic waveform synchronously with the horizontal deflection signal of a deflection yoke obtained from the circuit section 42 is modulated based on the current of nearly parabolic waveform synchronously with a half the vertical deflection period like a current of nearly parabolic waveform being an optional waveform. Thus, the current obtained from the coil 45 is supplied to the coil 41 correcting horizontal mis-convergence of the pattern intermediate part to correct the horizontal mis-convergence of the pattern intermediate part independently of the convergence correction at four corners on the pattern horizontal and vertical axes.

Description

[Detailed description of the invention]

[Purpose of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an in-line color picture tube convergence device, and more particularly to an in-line color picture tube convergence device for correcting horizontal misconvergence occurring in the middle of the screen.

0002

2. Description of the Related Art In general, an in-line color picture tube has an envelope consisting of a panel 1 and a funnel 2 integrally joined to the panel 1, as shown in FIG. Shadow mask 3 placed inside
A phosphor screen 4 consisting of a three-color phosphor layer in the form of vertically elongated stripes that emits blue, green, and red light is opposite to the phosphor screen 4.
is formed. Also, inside the neck 5 of the funnel 2,
An electron gun 7 is arranged that emits three electron beams 6B, 6G, and 6R arranged in a row, each consisting of a center beam 6G and a pair of side beams 6B and 6R that pass on the same horizontal plane. Three electron beams 6 are emitted from this electron gun 7.
Connect B, 6G, and 6R to the neck 5 and cone part 8 of the funnel 2.
The phosphor screen 4 is deflected by magnetic fields generated from the horizontal and vertical deflection coils 10H and 10V of the deflection yoke 9 mounted on the outside of the boundary between the phosphor screen 4 and the phosphor screen 4. It is formed into a structure that displays a color image on top.

In order to improve the quality of the image drawn on the phosphor screen 4, it is important to correctly converge the three electron beams 6B, 6G, and 6R over the entire screen. As a convergence correction means,
A convergence correction yoke 12 is arranged separately from the deflection yoke 9, and a convergence correction current such as a substantially parabolic waveform current or sawtooth waveform current synchronized with the deflection period of the deflection yoke 9 obtained from a convergence correction circuit 13 is applied to the convergence correction yoke 12. There is a method of dynamically correcting misconvergence in the horizontal direction by supplying the electron beams to the electron beams 6B, 6G, and 6R, regardless of the deflection of the deflection yoke 9 with respect to the electron beams 6B, 6G, and 6R.

In FIG. 4, reference numeral 14 indicates a magnet for correcting purity and static convergence.

In the above convergence correction means, as shown in FIG. 5, a convergence cup 16 is attached to the electron beam emission end of the electron gun, and a convergence correction yoke 12 is provided outside the neck 5 in correspondence with the convergence cup 16. Placed. The convergence correction yoke 12 includes a pair of U-shaped cores 17 and a convergence coil 18 wound around the cores 17. Normally, this convergence coil 18 is used to generate horizontal misconvergence XH on the horizontal axis (X axis) of the screen, where the blue, green, and red patterns are shown as 19B, 19G, and 19R in FIG.
and a coil for correcting horizontal misconvergence at the middle part on the horizontal axis, a coil for correcting horizontal misconvergence YH on the vertical axis (Y axis) of the screen, and a coil for correcting horizontal misconvergence at the middle part on the vertical axis. and horizontal misconvergence PQH at the four corners of the screen.
It consists of a coil for correcting. Further, this convergence correction means is magnetically coupled to the convergence correction yoke 12 so that the magnetic field 20 generated when the convergence correction current is passed through the coil 18 efficiently acts on the pair of side beams 6B and 6R. , a pair of side beam passage holes 2 of the convergence cup 16
Pole pieces 22 are placed with 1B and 21R in between.

As an example, in FIG. 7(a), a coil 18H for correcting the horizontal misconvergence XH on the horizontal axis of the screen and the horizontal misconvergence at the middle part on the horizontal axis has an approximately parabolic convergence correction current. The horizontal deflection synchronization correction circuit section 23 of the convergence correction circuit that supplies waveform current is shown. This circuit section 23
is composed of an LCR circuit having a coil 25 connected in series between the horizontal deflection coil connection terminals 24a, 24b and the coil 18H, and a variable resistor 26 connected in parallel to the coil 18H. Accordingly, a convergence correction current is generated for correcting the right side of the screen shown in FIG. 6 and the variable resistor 26 for correcting the left side of the screen.

The horizontal misconvergence XH on the horizontal axis of the screen and the horizontal misconvergence at the middle part on the horizontal axis are approximately parabolic waveforms obtained from the horizontal deflection synchronization correction circuit section 23 in synchronization with the horizontal deflection current 27. By supplying the current 28 to the coil 18H and generating a magnetic field in the convergence correction yoke 12, correction is performed for each scanning line (for each horizontal deflection scan), and uniform correction is performed over the entire screen.

In addition, as shown in FIG. 7(b), a nearly parabolic waveform is generated as a convergence correction current in a coil 18V for correcting the horizontal misconvergence YH on the vertical axis of the screen and the horizontal misconvergence in the middle part on the vertical axis. The vertical deflection synchronization correction circuit section 28 of the convergence correction circuit that supplies current is shown. This circuit section 28 is composed of a rectifier circuit 30 and an LCR circuit 31, each of which is a bridge connected in series between the vertical deflection coil connection terminals 29a, 29b and the coil 18V.

The vertical deflection synchronization correction circuit section 28 supplies a nearly parabolic waveform current obtained from the vertical deflection synchronization correction circuit section 28 to the coil 18V in synchronization with the vertical deflection current applied to the vertical deflection coil terminals 29a and 29b. By generating a magnetic field in the convergence correction yoke 12, uniform correction is performed over the entire screen.

Furthermore, regarding the correction of the horizontal misconvergence PQH at the four corners of the screen, since the correction is larger than the correction on the horizontal and vertical axes, the correction circuit is not shown in particular, but it is modulated by vertical deflection. This is done by passing a nearly parabolic waveform current (or sawtooth wave current) with the horizontal deflection period into a coil for correcting horizontal misconvergence PQH at the four corners of the screen, which is wound around the core of the convergence correction yoke.

[0011]

[Problems to be Solved by the Invention] As described above, a convergence correction yoke is arranged outside the neck corresponding to the convergence cup attached to the electron beam emitting end of the electron gun, and a pair of side faces are attached to the convergence cup. A pole piece is placed across the beam passage hole, and three types of coils are individually wound around the core of the convergence correction yoke. A coil for correcting directional misconvergence, a coil for correcting horizontal misconvergence YH on the vertical axis of the screen, a coil for correcting horizontal misconvergence at the middle part on the vertical axis, and a horizontal misconvergence P at the four corners of the screen.
The coil for correcting QH is supplied with a nearly parabolic waveform current or sawtooth wave current synchronized with the horizontal deflection current, a nearly parabolic waveform current or sawtooth wave current synchronized with the vertical deflection current, and a vertical waveform current from the convergence correction circuit, respectively. By supplying an approximately parabolic or sawtooth wave current with a horizontal deflection period modulated by the deflection,
Misconvergence on the screen horizontal axis, vertical axis, and at the four corners of the screen is corrected.

That is, a nearly parabolic wave current or a sawtooth wave current synchronized with the horizontal deflection current is applied to the coil for correcting the horizontal misconvergence XH on the horizontal axis of the screen and the horizontal misconvergence in the middle part on the horizontal axis. , the horizontal misconvergence of the same amount as the horizontal misconvergence XH on the horizontal axis is corrected over the entire screen. In addition, by flowing a nearly parabolic waveform current or a sawtooth waveform current synchronized with the vertical deflection current to the coil for correcting the horizontal misconvergence YH on the vertical axis of the screen and the horizontal misconvergence at the middle part on the vertical axis, The same amount of horizontal misconvergence as the horizontal misconvergence YH on the vertical axis is corrected over the entire screen. Furthermore, by flowing a nearly parabolic waveform current or a sawtooth wave current with a horizontal deflection period modulated by vertical deflection through a coil for correcting horizontal misconvergence PQH at the four corners of the screen, the horizontal misconvergence at the four corners of the screen can be corrected. PQH is corrected.

However, in general, the approximately parabolic waveform current or sawtooth waveform current required for the above-mentioned convergence correction is synchronized with the horizontal and vertical deflection of the deflection yoke. It is supplied to and formed by a vertical deflection synchronization correction circuit. Therefore,
It varies due to variations in the horizontal and vertical deflection coils of the deflection yoke, assembly errors of the electron gun, etc., and does not include the horizontal and vertical axes of the screen, as well as the first and final scanning lines that are ultimately displayed on the screen. Horizontal misconvergence may occur in the middle. In this case, if the horizontal misconvergence in the middle part can be corrected independently of the horizontal convergence correction on the horizontal axis, the vertical axis, and the four corners of the screen, the effort and time required to correct the convergence of the entire screen can be saved, making it extremely effective.

The present invention has been made in view of the above-mentioned problems, and is directed to the horizontal axis on the screen, the vertical axis, and the horizontal direction in the intermediate area that does not include the first scanning line and the final scanning line displayed on the screen. The object of the present invention is to construct an in-line convergence device for a color picture tube that can correct misconvergence independently of horizontal convergence correction on the horizontal axis, vertical axis, and four corners of the screen.

[Configuration of the invention]

[0016]

[Means for Solving the Problems] In an in-line color picture tube convergence correction device, the convergence correction device is attached to an electron gun that emits three electron beams arranged in a row consisting of a center beam and a pair of side beams. a convergence cup located within, a pair of cores and a first scanning line displayed on the screen;
a coil wound around the pair of cores in order to correct horizontal misconvergence in the middle part of the screen that does not include the final scanning line and the horizontal and vertical axes of the screen, a convergence correction yoke located outside the neck; a horizontal deflection synchronization correction circuit section that generates a nearly parabolic waveform current in the coil in synchronization with the horizontal deflection period of the deflection yoke; A vertical deflection synchronization correction circuit section that modulates a substantially parabolic waveform current synchronized with a 1/2 period, and a current waveform modulation coil section that modulates a substantially parabolic waveform current that is modulated in synchronization with a 1/2 period of the vertical deflection period. and a pole piece attached to the convergence cup and magnetically coupled to the convergence correction yoke to shape the magnetic field generated from the convergence correction yoke in the pair of side beam passing regions.

[0017]

[Operation] As described above, a coil is wound around the core of the convergence correction yoke to correct horizontal misconvergence in the middle of the screen, and a nearly parabolic waveform is modulated in synchronization with 1/2 period of the vertical deflection period. When a current is supplied to the coil and a magnetic field is generated from the convergence correction yoke, horizontal errors in the middle of the screen can be corrected independently of the conventional convergence correction on the horizontal axis, vertical axis, and four corners of the screen. Convergence can be corrected.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on embodiments with reference to the drawings.

The convergence correction device for a color picture tube of this example, like the conventional convergence correction device shown in FIG. 4, includes a convergence cup attached to the electron beam emission end of the electron gun of the in-line color picture tube;
Corresponding to this convergence cup, there is a convergence correction yoke placed outside the neck where the electron gun is located, a convergence correction circuit that drives this convergence correction yoke, and a pair of side beam passage holes in the convergence cup. It consists of a pole piece that is placed between them and magnetically couples with the convergence correction yoke. The convergence cup, convergence correction yoke, and pole piece are arranged in the same relationship as the conventional one shown in FIG.

By the way, the convergence correction yoke of the convergence correction device for a color picture tube in this example includes a coil for correcting the horizontal misconvergence XH on the horizontal axis of the screen and the horizontal misconvergence in the middle part on the horizontal axis, and A pair of coils wound around a coil for correcting horizontal misconvergence YH on the vertical axis and horizontal misconvergence at the middle part on the vertical axis, and a coil for correcting horizontal misconvergence PQH at the four corners of the screen. U-shaped core 17 (see Figure 5)
is a common core, and this core and the coils wound around this core independently of the above-mentioned coils, that is, the first scanning line displayed on the screen, the final scanning line, and the horizontal and vertical axes of the screen. It consists of a coil for correcting horizontal direction misconvergence in the middle part of the screen that does not include.

The convergence correction circuit that drives this convergence correction yoke, as shown in FIG. A horizontal deflection synchronization correction circuit section 42 is connected to a coil 41 for correcting convergence, and a vertical deflection synchronization correction circuit is connected to the vertical deflection coil of the deflection yoke via vertical deflection coil connection terminals 43a and 43b. It consists of a circuit section 44 and a current waveform modulation coil section 45 inserted between the correction circuits 42 and 44 for modulating the current waveform.

The horizontal deflection synchronization correction circuit section 42 is for generating a substantially parabolic waveform current synchronized with the horizontal deflection of the deflection yoke, and is shown as a block in FIG. Conventional LC shown in Figure 7(a)
The horizontal deflection synchronization correction circuit section consisting of the R circuit can be diverted or shared.

The vertical deflection synchronization correction circuit section 44 also has a capacitor 47 connected between vertical deflection coil connection terminals 43a and 43b. Further, a capacitor 49 is connected in parallel with this capacitor 47 via a variable resistor 48. Furthermore, variable resistors 50a and 50b are connected in parallel with the capacitor 47, respectively.
variable resistor 51a and diode 52a through 0a
are connected in parallel, and a diode 53a is connected to the parallel variable resistor 51a and diode 52a. Similarly, a variable resistor 51b and a diode 52b are connected in parallel via a variable resistor 50b, and a diode 53b is connected to the parallel variable resistor 51b and diode 52b.
is connected. Furthermore, the diode 53a
, 53b is connected to the output side of the capacitor 54.

In this circuit, the return line portion 55 of the sawtooth vertical deflection current of the deflection yoke shown in FIG. 2(a) is erased by the capacitor 47 connected between the vertical deflection coil connection terminals 43a and 43b. And that capacitor 4
7 and the rectification characteristics of the diodes 51a and 52a connected via the variable resistor 50a and the rising voltage vs. current characteristics during rectification, as shown in FIG. 2(b).
A substantially parabolic waveform current 56a shown in FIG. 2A is formed corresponding to the first half portion 57a of the vertical deflection current shown in FIG. 2A. Similarly, due to the rectification characteristics of the diodes 51b and 52b connected via the variable resistor 50b and the rising voltage vs. current characteristics during rectification, the latter half of the vertical deflection current 57b
A substantially parabolic waveform current 56b corresponding to the current 56b is formed. In this case, variable resistors 48, 50a, 51a, 50
b, 51b, the first half of the vertical deflection current 56a
The shape of the substantially parabolic waveform currents 57a and 57b corresponding to the second half portion 56b can be changed. The approximately parabolic waveform currents 57a and 57b synchronized with 1/2 of the vertical deflection period are generated by the diode 5.
Capacitor 54 connected to the output side of 3a, 53b
The phase is adjusted by

The current waveform modulation coil section 45 is composed of a coil connected to the horizontal deflection synchronization correction circuit section 42 and a coil connected to the capacitor 54 of the vertical deflection synchronization correction circuit section 44, The nearly parabolic waveform current synchronized with the horizontal deflection of the deflection yoke obtained from the correction circuit section 42 is adjusted by the magnitude of the nearly parabolic waveform current synchronized with the 1/2 period of the vertical deflection period as shown in FIGS.
As shown in (e), the currents are modulated into arbitrary, almost parabolic waveform currents 58a to 58c.

Therefore, this current waveform modulation coil 44
By supplying the coil 41 with a nearly parabolic waveform current modulated into a predetermined waveform obtained from , green, red pattern 6
It is possible to efficiently correct horizontal misconvergence in the middle part of the screen that does not include the first scanning line, the final scanning line, and the screen horizontal and vertical axes displayed on the screen shown as 0B, 60G, and 60R.

[0027]

Effects of the Invention: A convergence correction yoke located outside the neck is attached to an electron gun that emits three electron beams arranged in a row, consisting of a center beam and a pair of side beams, and is located inside the neck. A coil that corrects horizontal misconvergence in the middle of the screen is wound around a pair of cores independently of the coil that corrects horizontal misconvergence in the horizontal axis, vertical axis, and four corners of the screen, and a convergence correction circuit is wound around this coil. When configured to supply a nearly parabolic waveform current in which a nearly parabolic waveform current synchronized with the horizontal deflection of the deflection yoke is modulated by a nearly parabolic waveform current synchronized with 1/2 of the vertical deflection period, the screen horizontal axis and vertical axis And, independent of horizontal convergence correction at the four corners of the screen, efficiently correct horizontal misconvergence in the middle of the screen that does not include the first scan line, last scan line, and screen horizontal and vertical axes displayed on the screen. As a result, the convergence accuracy can be improved and the workability of convergence adjustment can be improved.

[Brief explanation of the drawing]

FIG. 1 is a convergence correction circuit diagram of an in-line color picture tube convergence device that is an embodiment of the present invention.

[Fig. 2] Fig. 2(a) is a vertical deflection current waveform diagram of the deflection yoke, and Fig. 2(b) is a diagram of the approximately parabolic waveform current formed in response to the vertical deflection current by the vertical deflection synchronization circuit section of the convergence correction circuit. The waveform diagrams in FIGS. 2(c) to 2(e) are waveform diagrams of approximately parabolic waveform currents having different waveforms obtained from the current waveform modulation coil section of the convergence correction circuit.

FIG. 3 is a diagram for explaining a method of correcting horizontal direction misconvergence in the middle part of the screen using an in-line color picture tube convergence device according to an embodiment of the present invention.

FIG. 4 is a diagram showing the configuration of an in-line color picture tube equipped with a conventional convergence device.

FIG. 5 is a diagram showing the configuration of the convergence device.

[Figure 6] Horizontal misconvergence on the horizontal axis of the screen and horizontal misconvergence in the middle of the horizontal axis, horizontal misconvergence on the vertical axis of the screen and horizontal misconvergence in the middle of the vertical axis, screen by a conventional convergence device. FIG. 6 is a diagram for explaining a method of correcting horizontal direction misconvergence at four corners.

FIG. 7 is a circuit diagram showing the configuration of a horizontal deflection synchronization correction circuit section of a conventional convergence device.

FIG. 8 is a circuit diagram showing the configuration of a vertical deflection synchronization correction circuit section.

[Explanation of symbols]

7...Electron gun 9...Deflection yoke 10H...Horizontal deflection coil 10V...Vertical deflection coil 13...Convergence correction circuit 12...Convergence correction yoke 16...Convergence cup 17...Core 21B, 21R...Pair of side beam passage holes 22...
Pole piece 44...Vertical deflection synchronization correction circuit section 45...Current waveform modulation coil section

Claims (1)

[Claims] Claim 1: A convergence cup that is attached to an electron gun and located in the neck and emits three electron beams arranged in a row consisting of a center beam and a pair of side beams, a pair of cores, and a convergence cup that is displayed on a screen. 1 scan line,
It consists of a coil wound around the pair of cores to correct horizontal misconvergence in the middle of the screen that does not include the final scanning line and the horizontal and vertical axes of the screen. a convergence correction yoke located outside; a horizontal deflection synchronization correction circuit section that generates a nearly parabolic waveform current in the coil in synchronization with the horizontal deflection period of the deflection yoke; A convergence device having a vertical deflection synchronization correction circuit section that modulates a substantially parabolic waveform current synchronized with two periods, and a current waveform modulation coil section that modulates a substantially parabolic waveform current that is modulated in synchronization with a half period of the vertical deflection period. A correction circuit, and a pole piece attached to the convergence cup and magnetically coupled to the convergence correction yoke to shape the magnetic field generated from the convergence correction yoke in the pair of side beam passing regions. An in-line convergence device for color picture tubes.