KR20010027424A - Convergence device for a color picture tube - Google Patents

Abstract

PURPOSE: A convergence device of a color Braun tube is provided to improve an image spreading effect and obtain a white balance according to a focus by controlling individually a side beam or an R beam. CONSTITUTION: A convergence device of a color Braun tube comprises a plurality of pair. The pairs are composed of a couple of magnet ring, respectively. The convergence device has a half-multi-polar correction magnet(P3) to locate a center magnetic pole to an outside of a side beam by arranging two magnetic poles or multi-magnetic poles. The half-multi-polar correction magnet(P3) is composed a pair having a couple of ring. The convergence device further comprises a landing control magnet of bipolar pair.

Description

Convergence device for a color picture tube}

FIELD OF THE INVENTION The present invention relates to color CRTs, and more particularly to a convergence device.

The color CRT is an aperture type that emits R, G, and B phosphors with a single electron beam, and a trio type and in-line type that independently emits three electron beams for each phosphor. However, in-line type tubes that are easy to manufacture electron guns and fluorescent screens are mainly used for consumer CRTs such as TVs.

In-line color CRT forms three electron guns in which the electron gun assembly is arranged side by side. As shown in FIG. 1, the electron beam 20 emitted from the three electron guns 10 is in a raster state. It should be converged to a point on the fluorescent surface 40 through a shadow mask 30.

In this case, the electron beam 20 scans each position on the fluorescent surface 40 by horizontal and vertical deflection means 50. In this scanning, the three electron beams 20 should be converted to one point at each position. .

Accordingly, the color-brown tube is provided with static and dynamic convergence means, which are referred to collectively as P, P2, P4 and P6; It is generally composed of a convergence device called CPM (Convergence Purity Magnet).

Here, each pair P2, P4, P6 of the convergence device is partially magnetized and is composed of two magnet rings forming two kinds of poles, N and S.

First, the bipolar pair P2 shown in FIG. 2A is called a purity magnet. As shown in FIG. 2A, the three R, G and B beams are generated by the magnetic flux between the N pole and the S pole. Will move in one direction.

Meanwhile, the 4-pole pair P4 shown in FIG. 2B moves two R and B beams in opposite directions to each other. The two beams are moved in the same direction, and the 4-pole pair P4 and the 6-pole pair P6 are called convergence magnets together.

The convergence device is used to adjust the three R, G, B electron beams are not aligned correctly due to errors in the manufacturing process of the color CRT, each pair (P2, P4, P6) is composed of a pair of magnet ring The reason for this is to adjust the convergence by adjusting the beam shift amount for different manufacturing errors for each CRT by adjusting the relative angle therebetween.

Such convergence adjustment is sufficient in consumer CRTs such as TVs, but in industrial CRTs and high-end CPTs used for computer monitors, accurate focus adjustments require white balance; Abbreviated below as WB).

Here, WB means the whiteness of the white spot formed when the three beams of R, G, and B are simultaneously turned on. Since the luminous efficiency of the R, G, and B phosphors becomes R <G <B, The intensity of the electron beam passing through must be R> G> B so that an appropriate WB can be achieved on the screen. Since the intensity of the electron beam passing through the color screening means depends on the accuracy of the landing of each beam, the landing of each beam is properly adjusted, that is, the state in which the focus is accurately achieved to achieve the WB.

To this end, in the CDT, as illustrated in FIG. 3A, a 2-pole pair P2 of the convergence apparatus P is disposed on the deflection apparatus DY, and a separate 2-pole pair P2 'is disposed. It is intended to improve image quality such as focus and achieve WB by using the focus correction magnet to compensate for the R-beam's spreading phenomenon. Since the remaining code P4 'is not directly related to the B / R adjustment magnet by the 4-pole pair or the present invention, description thereof will be omitted.

However, since the focus correction magnet P2 'is basically a two-pole pair described with reference to Fig. 2A, as shown in Fig. 3B, the R, G, and B beams are shifted by the same degree in the same direction ( In this case, if one beam is corrected, the other two beams are separated from each other, so that only the required beams can be adjusted independently.

The problem here is that the side beams, especially the phosphors, have a very low luminous efficiency, which is an R beam that requires a large electron beam intensity. When the focus is adjusted to improve the R beam spread, the G and B beams are shifted out together. As a result, the red color reproducibility is deteriorated, and thus, WB is not achieved, which causes a problem of deteriorating the image quality of the CPT and incapable of implementing the original function of the CDT, which makes life accurate.

In view of such a conventional problem, an object of the present invention is to provide a convergence device capable of individually adjusting side beams, particularly R beams, to improve the spreading phenomenon and achieve focus and thus WB.

1 is a schematic cross-sectional view showing the configuration of an inline color brown tube;

2 (A) to (C) are schematic diagrams showing the function of each pair of convergence devices;

3 is a view showing a conventional focus adjustment configuration, (A) is a schematic configuration diagram, (B) is a beam cross-sectional view,

4 is a front view of a phase spreading correction magnet constituting the convergence device of the present invention;

5 (A) and (B) are schematic configuration diagrams showing preferred embodiments of the convergence device of the present invention,

6A to 6D are front views showing various possible configurations of the correction magnet of the present invention.

<Description of the code | symbol about the principal part of drawing>

P: convergence device

P2, P4, P6: (2-pole, 4-pole, 6-pole) pair

P2 ': Focus correction magnet (by 2 pole pair)

P3: (Invention) Half 3-pole Correction Magnet

In order to achieve the above object, the convergence device of the present invention is characterized by locating a half-multipole correction magnet having two or more poles arranged on one side in a single ring or a pair and located outside the side beam. An additional feature is that the anti-polarity correction magnet is used in parallel with a conventional focus correction magnet using a two-pole pair.

As a result, individual adjustment of side beams such as R beams to R phosphors having particularly low luminous efficiency can be performed, thereby improving color spreading, which enables the implementation of color CRTs having excellent focus characteristics, WB, and image quality.

Such specific features and advantages of the present invention will become more apparent from the following description of the preferred embodiments with reference to the accompanying drawings.

Example

In Fig. 4, the half-pole correcting magnet constituting the convergence device of the present invention is composed of three-pole magnets P3 with three magnetic poles of NSN or SNS disposed adjacent to one half thereof, and the central magnetic poles are R, G, and B. The three beams are arranged adjacent to the side beams, in particular the R beams.

The magnetic flux applied to the three R, G, and B beams becomes R >> G> B by the configuration of the anti-polar pole correction magnet, so that the side beams, in particular, the R beams can be individually adjusted.

In this case, the three-pole magnet P3 is preferably composed of a half-pole pair of two rings paired together with other magnets for adjustment, but adjustment by the other pairs P2, P4, and P6 may be appropriately performed. If possible, it may consist of a single ring, rather than a pair, to function by shifting the adjustment state by a certain amount.

FIG. 5 illustrates a convergence device using the present invention half-pole magnet P3 as a phase spread correction magnet. First, in FIG. 5 (A), the half-pole magnet P3 is constituted by a pair, and is located behind the convergence device P in front of the electron gun 10 to function as an upper spreading correction magnet.

On the other hand, in the configuration of Fig. 5 (B), the focus correction magnet P2 'by the conventional two-pole pair is located at the rear of the deflection device DY, and the pair of the half-pole magnet P3 of the present invention is connected to the convergence device P. Located in the rear, the half-pole magnet P3 individually adjusts the R-beams while the conventional landing adjusting magnet P2 'adjusts the three R, G, and B beams by the same amount. On the other hand, even in the case where a problem such as the spreading of the B beam, which is another side beam, becomes a problem, individual adjustment of only the B beam is similarly possible. Here, the landing adjustment magnet P2 'by the two-pole pair may be located in front of P4 of the convergence device P as needed.

6 (A) to (D) show various embodiments of the anti-pole polarization correction magnet according to the present invention. First, (A) is a half-pole, as already shown and described in Fig. 4, (B) is a half-pole by NS two-pole, (C) is a half-pole by four poles, and (D) is a half-pole. Configuration. In either embodiment, two or more poles, preferably six poles or less, are disposed only on one side half of the ring-shaped correction magnet to selectively adjust only the side beams.

As described above, according to the present invention, since the luminous efficiency of the phosphor is significantly low, the image spreading phenomenon is remarkable, and the side beams such as R beams requiring large electron beam intensity and accurate landing can be individually adjusted, and thus, WB is easily achieved and red color reproducibility is achieved. It is effective to realize this excellent high quality color CRT.

Claims (3)

In the convergence device of a color brown tube having a plurality of pairs each consisting of a pair of magnet rings in which a plurality of magnetic poles are formed, A half-pole polarization correction magnet for arranging a plurality of magnetic poles adjacent to two or more poles on one side thereof and positioning the central magnetic pole outside of the side beam. The method of claim 1, And said half-pole correcting magnet is composed of a pair of pairs of rings. The method of claim 1, A landing adjustment magnet by a two-pole pair is further provided in the convergence device and / or the deflection device. And R, G, B three beams are adjusted to the same amount by the landing adjustment magnet, and the side beams are individually adjusted by the anti-pole polarization correction magnet.