JPS5968150A - Cathode-ray tube - Google Patents

Abstract

PURPOSE:To concentrate three electron beams on almot one point on a screen by inserting a focusing member without mutually deflecting the central axes of the electron beam through holes of opposed electrodes that comprise relative principal focusing lenses. CONSTITUTION:When a focusing member 6 is inserted, the equipotential surface 7 of an electric field forms rotational symmetry for the central axis in the aperture of a final electrode 1, but it is located in the reverse direction with the central axis 5 with regard to the central axis 3 as the surface advances to the electron beam advance direction. Thus, the side electron beam is focueed in the direction of the central axis 5 and three electron beams are substantially deflected on a screen so as to be concentrated. However, since the focusing member 6 has the same central axis as the aperture central axis 3 of the final electrode 1, an electron lens is not distoted on the opposed surface of a principal electron lens and the electron beam focusing spot becomes a good circle and then a picture with good resolution can be obtained. In this case, it is important that the central axis 3 of the final electrode 1 should align the central axis of the focusing member, and the good electron beam focusing spot can be obtained by doing so.

Description

DETAILED DESCRIPTION OF THE INVENTION TECHNICAL FIELD OF THE INVENTION The present invention relates to cathode-like tubes, and more particularly to shadow-mask type collar single-hole tubes.

Technical Background of the Invention In general, a color cathode tube electron device consists of three electron guns each consisting of a plurality of grids. The beam is focused and the electron beam is made to strike a screen.Normally, the method of converging three parallel electron beams emitted from a cathode on a screen is as follows:
A known method is to deflect the electron beam by slightly decentering the center axis of the electron beam passage hole of the counter electrode forming the electron lens.

With reference to the drawings, a deflection means for concentrating and matching the plurality of beams of a conventional electron gun device will be explained. No. 11) shows the final magnetic pole of the conventional electron gun device. i & final electrode (1)
(hereinafter referred to as G6) is normally applied with a high voltage of 20 to 25 KV. G6 (1) is an electron beam passage hole (1-a) corresponding to the three electron beams passing through.

(1-b), (1-c), and a focus electrode (2)
(hereinafter referred to as G5) is separated by a distance C. G5 (
In 2), a wind pressure of 7 KV to 8 KV is usually applied, and the distance C between the upper poles is selected to be about 1 nrm.

G5 (2) (=also G6 (1), passing holes corresponding to three electron beams (2-a), (2b),
(2-c) is provided. G5 (2) and G6 (
The central axes (5) of the center holes in 1) coincide, but G6 (1
) and the corresponding central axis (4) of the outer passage hole of G5 (2) are connected to the central axis (4) of the outer passage hole of G6 (1) in order to concentrate the three electron beams on the screen 1. The central axis (3) of G5 (2) is offset from the central axis (4) of G5 (2) by b in the external measurement direction from the central axis (5) of the central hole. The value of b is the central axis (5) of the central hole (2-b) of G5 (2) and the outer passage hole (2-a).

Distance a between center axis (4) of (2-b) (different from 2, but usually a = 6. (for 3 mm, 'D'' 0.2 r
ut-also if a==4.9 mm then b=0.1
l'f of about 3 mm? It is.

Problems with the Background Art According to the electron gun device (-), which has a single configuration, the focused spot of the electron beam on the screen becomes elliptical, the bright spot on the screen becomes larger, and the resolution deteriorates significantly. For this reason, in the cathode ray tube disclosed in Japanese Patent Publication No. 52-32714, the above-mentioned drawback is improved by curved 441 the counter electrode arranged on the screen side.However, the above-mentioned structure (In the second 'id sub-gun device, the distance C between the electron beam passing holes in the opposing electrodes is as short as d/2 or less with respect to the diameter d (Z) of the beam passing hole, so the main electron lens formed between the opposing magnetic poles is (Distortion occurs due to the electric field of two adjacent apertures, and the electron beams on both sides pass through the most distorted part of this main electron lens, so the electron beams on both sides are subject to large distortions, resulting in the brightness of the screen surface.) Unfortunately, I was unable to prevent the resolution from deteriorating.

OBJECTS OF THE INVENTION The object of the present invention is to improve such drawbacks ('''-). By interposing a focusing member, three electron beams are IF on the screen.

The object of the present invention is to provide a cathode ray tube that can be focused on a single point.

In the present invention, a focusing part 1lIj having an electron beam passing hole is interposed in at least one of opposing magnetic poles forming a focusing lens, and at least a part of the electron beam passing hole of this member is arranged in the tube axis direction ( The electron beam passing through the focusing lens is formed so that the length of the electron beam passing hole in the tube axis direction is different at each position on the circumference of the electron beam passing hole. to concentrate on (=substantial (-
It is something that deflects.

Examples of the invention Embodiments of the present invention will be explained using two drawings.

FIG. 2 is an overview diagram showing the focusing member (6). The focusing member (6) consists of a plate member (6-1) with three electron beam passage holes, two cylindrical members (6-2), and side cylindrical members (6-3) with different peripheral heights. This is what I added.

Such a focusing member (6) can be manufactured, for example, by press molding, drawing, etc.

Further, as shown in No. 21, the side cylindrical member (6-3) is made to have a high peripheral height at a portion close to the central cylindrical member (6-2). Again, 1 is not shown, but the side circle is 1itT
The peripheral height of the member (6-3) is the center of the cylindrical part (= the closer it is, the lower it is formed, or the combination of both. In other words, the axial center of the electron beam passage hole and the tube axial center A cylindrical member is formed with different lengths in the tube axis direction at the circumferential position of the focusing member cut by a line segment connecting the focusing member.

FIG. 3 shows a cross section of the main electron lens section when the main focusing lens is attached to the focusing member shown in FIG. Third
Attach the focusing member (6) shown in Figure 2 (=) to G6 (1) in the figure.The attachment method may be by fitting, welding, etc., or by crimping, etc. The central axis of the electron beam passage hole (5) in the center is Gfj (1) and G5 (
2) and the focusing member (6) all have the same central axis, but the side electron beam passage hole central axis (3) also has the same central axis as G6 (1) and 05 (2) and the focusing member (6). 6) all have the same central axis. G6 (1
) and 05(2), if there is no focusing member (6), both electron beams will travel straight, and the two electron beams will not be concentrated on the screen surface. When the focusing member (6) is present, the equipotential surface (7) of the electric field is the third one.
As shown in the figure, at the G6 (1) aperture, the electron beam is rotationally symmetrical with respect to the central axis, but the electron beam advances in the direction (-therefore, with respect to the central axis (3)) - in the opposite direction (two directions) to the central axis (5). Due to the position, the side beams are focused towards the central axis (5) and are deflected so that substantially two electron beams are concentrated on the screen surface.However, the focusing member (6) G(i (1) lHm Since it has the same central axis as the mouth center axis (3) (the electron lens is not distorted on the opposing surfaces of the two main electron lenses, the electron beam focused spot has a good circular shape). , images with good resolution can be obtained.At this time (2G6(
It is important that the central axis (3) of 1) and the central axis of the focusing member match, and doing so (=therefore a good
m electron beam focused spots are obtained. Therefore, the shortest dimension of the focusing member in the direction of the tube axis, indicated by g, is important, and makes it possible to form an electron lens that is not misaligned with the central axis (3).

In such a case, the conditions are 4 strokes in G6 (1), G5 (2)
When a heavy pressure of 8 KV is applied to the center and side electron beam passage holes, the distance between the central axes a = 5, the longest dimension of the focusing member in the tube axis direction of a 19 V inch 90° deflection tube is f = It has been confirmed that a thickness of 0.4 mm, g=0.5 mm, and a thickness of the focusing member (6) of 0.32 mm are sufficient. In addition, dimensions f and g are also available for other tube sizes such as 11 inches and other inch sizes such as 25V inches, and cathodes and friction tubes with various deflection angles such as 76°, 100', and 110'.
That is, by adjusting the inclination of the opening of the focusing member (6) with respect to the central axis (3), the two electron beams can be well concentrated on the screen surface. Also in this case, since the central axis of the focusing member (6) coincides with the central axis of G6 (1), the electron beam focusing spot is not distorted and a screen with good resolution can be obtained. The focusing member (6) also acts on the central electron beam;
A good screen can be obtained by adjusting the effect of the focusing part (6) on the side electron beam and the focusing effect on the medium-fired electron beam to the same degree and using it to adjust the shape or size of each electron beam focusing spot. It will be done.

FIG. 4 shows an embodiment in which the present invention is used in an electron gun device using an electron gun member different from that of the previous embodiment. FIG. 4 is a diagram mainly for explaining the main focusing lens, and is a diagram mainly for explaining the main focusing lens.
), G5 (2) is actually the center axis (3) in addition to the illustration.
) and (5) are attached to form the electron gun device at 41°q. The focusing member is the same as that shown in FIG.

FIG. 5 shows another preferred embodiment of the present invention. In this embodiment, the focusing member (6) is also attached to the G5(2)" electrode, and the focusing member (6a) is attached to the central axis (3).
.

The inclination of the open portion surface of (6b) may be small, and the focusing effect of the side electron beam is improved. Therefore, compared to the embodiments shown in FIGS. 3 and 4, the size and distortion of the electron beam focused spot on the screen surface are smaller and an image with even higher resolution can be obtained. Good results can also be obtained when the embodiment shown in FIG. 5 is used in an electron gun device using electron gun components such as those shown in the embodiment shown in FIG.

In the above embodiments, a so-called in-line type electron gun device configuration has been described. In the in-line type electron gun device, there are three openings (G-a) in the focusing section (6).

Among (6b) and (6-c), the openings (6-a) and (6-c) of both side beams are at the center 1i1t
It suffices if it has a slope with respect to l (3). At this time, the medium heat opening (6-b) is preferably perpendicular to the central axis (5).

FIG. 6 is a schematic diagram showing an example of the mounting member (8) when the present invention is implemented in a delta-type electron gun.

When applied to a delta array electron gun, the two electron beam passing hole aperture surfaces (8-1), (8-2), (8-3)
is preferably inclined with respect to the central axis of each electron beam passage hole, but what is the opening surface of one passage hole? It is perpendicular to the central axis of the α electron beam passage hole, and the other two passage holes may be inclined with respect to the central axis of each electron beam passage hole.

FIG. 7 is a sectional view showing a preferred example of the present invention in which the focusing member (8) is attached to the main focusing lens of a delta-type electron gun device. Since it is a delta-type electron gun, it is not possible to show all three electron guns in the same plane, so only a cross-sectional view of the two electron guns is shown. When using a delta array electron gun device, the G
6 (1) and G5 (2) (it is also possible to attach two focusing members (not shown).

In addition, in both the in-line array electron gun device and the delta-type array electron gun device, the focusing member (
6) and (8) are integrated, but each has a three-electron gun (
1, separate members may be used.

In this case, the attachment to the electron gun device is fitted.

Any method such as welding or crimping may be used.

Effects of the Invention (2) According to the present invention (2), it is not necessary to decenter the central axis of the corresponding electron beam passing hole of the opposing stack forming the main electron lens, as has been conventionally known. In addition to being able to obtain high-resolution images with low distortion of the electron beam focused spot, there is also the advantage that 1. the electrodes 71) constituting the main electron lens can be made of the same component.Therefore, component manufacturing is possible. (2) The assembly of the electron gun can be easily made with high precision.Also, the main electron lens can be constructed from the same parts, reducing the variation in parts (2. Even if the part dimensions vary, However, the focusing effect and the diverging effect in the main electron lens are canceled out, and the effect on the lens effect of the main electron lens is small, which greatly contributes to lowering manufacturing yield and product defect rate. The industrial value of the invention is very high.

[Brief explanation of drawings]

FIG. 1 is a schematic cross-sectional view of the main parts of a conventional main electron lens configuration, FIG. 2 is a four-way external view showing a focusing member applied to the present invention, and FIG. 3 is an embodiment of the present invention. FIGS. 4 and 5 are schematic sectional views of the main parts showing other embodiments of the present invention, and FIG. A schematic sectional view showing another focusing member, and FIG. 7 is a schematic sectional view of the main part showing the main electron lens configuration used in the focusing member layer of FIG. 6. (1) -G6 'ttt (Gi (2) -G5'M
Pole (3)...Central axis of G6 side hole (4)...Central axis of G5 side hole (5)...Central axis of central hole (6), t81...
・Focusing member (7)... Equipotential surface

Claims (1)

[Claims] ■) Each of the electron beam passing holes for at least two electron beams is composed of a plurality of electrodes arranged on the same central axis,
The virtual center of gravity of at least two electron beams is 1i:1.
is disposed substantially coincident with the tube axis, and between at least two opposing electrodes of the plurality of electrodes (in a polar ray tube comprising an electron gun forming a square-flux lens, the focusing lens is A member extending through the electron beam passage hole is interposed on at least one of the opposing electrodes to be formed, and at least a part of the electron beam passage hole of the member forms a side wall extending in the tube axis direction, and A cathode ray tube characterized in that the length of the electron beam passage hole in the tube axis direction is different at each position on the circumference of the electron beam passage hole. 2) The line segment connecting the axial center of the electron beam passage hole and the tube axis center. 2. The cathode ray tube according to claim 1, wherein the lengths of the circumferential positions of the members cut in the tube direction ζ11 are different. 3) The aperture surface of at least one electron beam passing hole of the member on the opposite urine collecting magnetic pole side is inclined with respect to the central axis of the electron beam passing hole.
,+'rl'Claims! Cathode ray tube according to item 2.