JPS58145046A - Color picture tube - Google Patents

Abstract

PURPOSE:To obtain a shadow mask fully having sufficient mechanical strength and small beam halation, by forming a single groove to a screen side of stripe- shaped holes in the shadow mask and a groove, which consists of a node divided into two by a protrusion of a bridged part, to an electron gun side. CONSTITUTION:Stripe-shaped hole row groups consisting of many through holes 32 are formed on a shadow mask 30 and interposed between banks 31 holding a plate thickness of the whole mask in the direction at a right angle with a stripe direction. On the other hand, a group of the many holes 32 is formed to about a square shape separated by bridged parts 33 arranged in a proper distance respectively in the stripe direction. Further a single groove in thickness smaller than the bank 31 is formed in a screen side of the part 33 while protruded parts 33a and a groove in a state of recessed part 35 formed in both sides of said part 33a are provided to an electron gun side. In this way, the shadow mask fully provided with mechanical strength to suppress beam halation and good molding quality can be obtained.

Description

TECHNICAL FIELD OF THE INVENTION The present invention relates to a shadow mask type color picture tube, and particularly to a shadow mask having a group of striped holes.

Technical Background and Problems of the Invention In general, a shadow mask type color picture tube includes an electron gun means that emits an electron beam that excites phosphors that emit red, green, and blue colors, and a fluorescer that each electron beam corresponds to. It has a shadow mask placed close to the phosphor side between the phosphor and the electron gun so as to strike only the body. A so-called slit mask having striped holes is generally used as the shadow mask. Various proposals have been made regarding the hole shape of this slit-shaped shadow mask. For example,
Japanese Utility Model Publication No. 51-3733 discloses a color selection substrate (shadow mask) in which striped holes are divided into a plurality of holes C'' by bridges (bridges) provided at appropriate intervals. In the proposed method, an electron gun side hole of a striped hole is separated from adjacent holes by the bridge, and an opening on the fluorescent surface side of the hole is connected to an adjacent hole. As shown in Figure 1, this shadow mask 01) is a striped material with a thickness of 0.15mm, a pitch of 0.6nm, and a 0.3M wide opening on the phosphor surface side. When hole a2 is formed, the width of the striped hole on the electron gun side is 0.14 m, and the bridge is 0.1 m.
If the distance is 1 m, the width of the bridge on the electron gun side is 0.05 mm, and the thickness is 0.06 mm.

However, in reality, C: has a drawback that when such a shadow mask is molded into the required spherical shape, one nibriage is broken during molding because the tensile strength of the bridge portion is weak. In order to prevent the bridge from breaking, it is necessary to make the bridge width sufficiently long, 0.2 to 0.3 m, or to make the bridge thickness sufficiently thick, 0.13 to 0.15 m. However, if the bridge width is increased, when forming a striped phosphor by exposure, the bridge width (
There are two problems in exposure formation, and if the bridge thickness is increased, electron beam halation worsens, and in any case, it is difficult to implement.

OBJECTS OF THE INVENTION In view of the current situation, the present invention provides a shadow mask that is strong in mask forming, and also provides a color picture tube having a shadow mask that causes less screen formation and beam halation.

Summary of the Invention The present invention is based on the screen side (- indicates single-a) of the connecting bridge in the stripe direction of the striped holes of the shadow mask, and the electron gun side from the node bisected by the protrusion c2 of the bridge. By forming grooves, the striped pores are formed into a substantially rectangular shape, which has sufficient mechanical strength and good formability.
This color picture tube is equipped with a shadow mask that reduces electron beam halation and facilitates screen exposure formation.

Examples of the invention Below, two examples of the present invention will be described in detail.

The color picture tube of the present invention is the same as the conventional one except for the shadow mask, so a detailed explanation will be omitted.

FIG. 2 is a schematic partial perspective view showing an embodiment of the present invention (two shadow masks used together), and FIG. 3 is a schematic plan view of FIG. 2. As shown in C2, a striped hole array group consisting of a large number of through holes (32) is formed in the shadow mask holder.This striped hole array group maintains the thickness of the entire shadow mask in the direction perpendicular to the stripe direction. ).On the other hand, a large number of through holes (group 3Z) are separated by bridge parts □□□ arranged at appropriate intervals in the stripe direction, and have a roughly rectangular shape. ) is shown in Fig. 2 (2) It goes without saying that each stripe row may be arranged in a staggered manner or in a different arrangement as shown in Fig. 2. A single groove is formed thinner than the mask bank 01) on the electron gun side (downward side in the paper of FIG. 2) of the bridge (to). It has a protrusion (33a) and a groove in the form of a concave part 09 formed on both sides of the protrusion (33a).That is, each substantially rectangular through hole G
z is formed by a continuous single groove on the screen side, which is connected to each other, and at the same time, on the electron gun side (1) it is a striped groove having a node divided into two by a protrusion (33a). They are connected to each other via a gap 09 consisting of.Furthermore, details C2 will be explained using the cross-sectional views of FIGS. 4 to 7. FIG. The through hole G2 is formed by the large hole on the screen side (32a) and the small hole on the electron gun side (r32b), and the adjacent hole G2 is formed by the large hole on the screen side (32a) and the small hole on the electron gun side r32b). Matching through hole (32a
) are connected to each other, and the large hole (32a) forms a single striped recess as a whole. Electron gun side small hole (32
b) is separated by the protrusion (33a) of the bridge (331). FIG. 5 is a sectional view taken along line B-B' in FIG. 3, showing the end section of the through hole and the bridge. Similar to FIG. 4, in the large hole side through hole portion (32a), adjacent through holes (32a) are connected to each other via the bridge portion C331.Small hole portion r
32b) are connected via grooves G provided at both ends of the bridge portion (to), and form a single striped recessed portion as a whole. However, a protrusion (33a) is formed between the grooves C3!
) has a node bisected by

FIG. 6 shows a cc' cross section in FIG. 3. The surface of the through hole portion consists of a large hole side (32a) and a small hole side (32b), both of which are formed by chemical etching or the like. FIG. 7 shows a sectional view taken along line DD' in FIG. The bridge portion C33) formed between the banks (31) interposed between the striped hole rows is chemically etched in the plate thickness direction≦2 on the screen side, and is formed lower than the bank 01).

On the side of the small hole, there is a protrusion (33a) having a surface of approximately the same height as the side surface of the small hole (t34), and a groove (to) formed at both ends of the protrusion (33a).
has. It is preferable that the grooves 0ω are spaced close to each other in the through hole of the small hole (32b), but they do not necessarily have to be the same.

Effects of the Invention In the shadow mask C2 having striped holes configured as described above, even if the large hole sides are connected, and even if the bridge width is wider than the conventional one in order to strengthen the mask strength, When forming a screen, the hole shape is substantially (-
The rectangular shape facilitates the formation of a screen consisting of phosphor strips. Also, if a groove is formed at the center of the bridge,
Although the bridge becomes increasingly weak mechanically, the grooves are formed in the relatively thick bridge (1) The shape of the pores can be controlled without reducing the strength of the bridge.In this way, the cross-link By connecting not only the large hole side but also the small hole side of the
At the same time, it is possible to suppress electron beam halation, and at the same time, it is possible to obtain a shadow mask that is easier to form a screen and has good formability.

[Brief explanation of drawings]

FIG. 1 is a schematic partial perspective view showing a conventional shadow mask;
2 is a schematic partial perspective view showing an embodiment of a shadow mask applied to the present invention, FIG. 3 is a schematic plan view of FIG. 2, and FIG. 4 is a sectional view taken along line AA' in FIG. 3. 5 is a sectional view taken along line BB' in FIG. 3, FIG. 6 is a sectional view taken along line CC' in FIG. 3, and FIG. 7 is a sectional view taken along line DD' in FIG. (73] 7) Agent Patent attorney Noriyuki Chika (and 1 others)
given name)

Claims (1)

[Claims] An electron gun that emits a plurality of electron beams, a screen facing the electron gun and having a large number of phosphor strips, and a large number of striped holes arranged in rows disposed close to the screen in the stripe direction 1. : In a color picture tube equipped with a shadow mask having a large number of striped holes connected via a bridge, the striped holes are formed into a substantially rectangular shape I in the stripe direction by the bridge.
: A single groove is formed on the screen side of the bridging part, and a striped groove is formed on the electron gun side of the bridging part with a node divided into two by a protrusion provided on the bridging part sea. A color picture tube characterized by having a shadow mask.