JPH0361300B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field of the Invention The present invention relates to a mask-focusing color picture tube;
In particular, it relates to the method of supporting and fixing the mask.

Technical Background and Problems of the Invention Conventional color picture tubes have a problem of poor electron beam utilization because they have a shadow mask with a color selection mechanism.

A mask focusing color picture tube is a method for solving the above problem. A feature of the mask-focusing color picture tube is that while the shadow mask of a conventional color picture tube only has a color selection mechanism, the mask focusing type color picture tube increases the efficiency of electron beam utilization by increasing the mask hole size. Another object of the present invention is to form an electron lens in the mask through-hole to focus the passing beam onto the screen and increase the brightness.

FIG. 1 is a schematic diagram of a conventional color picture tube, which has an electron gun 1 that generates three beams, a shadow mask 2, and a screen 3 made of phosphors of three colors.

FIG. 2 is a schematic configuration diagram showing an example of a mask focusing type color picture tube, in which an electron gun 4 that generates three beams, an electron gun side mask electrode (hereinafter referred to as Mg) 5,
It has a screen-side mask electrode (hereinafter referred to as Ms) 6 and a screen 7 made of phosphors of three colors.
Ems and Es are applied, and in order to form an electron lens in the through hole, Es=Emg>Ems.

FIG. 3 is an enlarged view showing the vicinity of the screen in FIG. 1, and the three beams 10, 11 and 12 passing through the through hole 9 of the shadow mask 8 are approximately the same size as the through hole, and have three corresponding colors. The light collides with the fluorescent bodies 13, 14 and 15 of. 16 is an envelope panel section.

FIG. 4 is an enlarged view showing the vicinity of the screen in FIG. It is provided. The beams passing through the holes 17 and 18 are focused by the electron lenses as described above and are directed to the corresponding phosphors 2.
2, 23, and 24, respectively.

Here, since the shadow mask of a conventional color picture tube requires the same voltage as the screen voltage, the method of supporting and fixing it is easy. However, in the case of a mask focusing type color picture tube, a mask electrode that applies a voltage different from the screen voltage is required, so a mask electrode support and fixing technology that takes into account electrical insulation between the mask electrode and other structures is required. becomes.

FIGS. 5 and 6 show general mask support and fixing structures of a conventional color picture tube and a mask focusing type color picture tube.

In the case of the conventional color picture tube shown in Fig. 5, all structures near the mask have the same potential, so the mask 25
The skirt portion 26 of the mask is attached to the frame 27 for fixing the mask.
The mask 25 is supported and fixed by electric welding. The frame 27 is attached to the panel 28 via bimetal or the like.

In the case of the mask focusing type color picture tube shown in Fig. 6, the frame 30 and Mg3 attached to the panel 29 are
1 have the same potential, so they can be fixed by electric welding as in the conventional case. However, since it is necessary to apply different voltages to Ms32, it must be fixed via an insulator 33. In this case, since the Mg effective surface 34 and the Ms effective surface 35 are spaced apart from each other to a certain extent in advance, it is best to fix them with the skirt portion 36.

Fig. 6 If the shape is as it is, the Mg skirt outer surface 3
7 and the Mg side surface 38 of the insulator, and
It is necessary to adhere the Ms side surface 39 and the Ms skirt inner surface 40, and the reliability is halved because the adhesive points are doubled.

Technically, since surfaces are bonded together, the characteristics of the adhesive and the bonding method are major issues. To give a specific example, when an adhesive is applied before pressing to form a curved surface of a shadow mask, the characteristics of the adhesive are that it does not adhere to the press mold and is heated after pressing. It must be such that it can restore its adhesive ability when exposed to heat. Furthermore, if the thickness of the adhesive changes during bonding after pressing, this is undesirable as it may cause holes to be misaligned between the masks.

OBJECTS OF THE INVENTION The present invention has been made in view of the above points, and an object of the present invention is to support and fix the mask of a mask focusing type color picture tube with high precision.

Summary of the Invention The mask focusing type color picture tube of the present invention is provided with through holes in the skirt portion of the mask electrode and the insulator, at least a portion of the through holes overlap, and an insulator interposed in the overlapping portion. This is to relatively fix the two mask electrodes.

Examples of the invention Examples of the invention will be described below. The mask focusing type color picture tube of the present invention is the same as that shown in FIG. 2 except for the mask support structure, so the explanation of the overall structure will not be repeated here.

FIG. 7 is a partially enlarged schematic diagram showing an embodiment of the present invention, showing a through hole 42 provided in Mg41 and an insulating material 4.
A through hole 44 provided in Ms. 3 and a through hole 46 provided in Ms 45 are filled with an insulating agent 47 to relatively fix the mask electrodes. 8 to 10 are partially enlarged schematic diagrams showing other embodiments of the present invention.
Figure 8 shows an example in which through holes are provided only in Ms and the insulator.

FIG. 9 is similar to FIG. 7, but a screw 48 made of an insulator is inserted instead of the insulator. FIG. 10 is an example of a case where the size of the through hole is changed. It goes without saying that combinations of the embodiments shown in FIGS. 7 to 10 are also possible.

Effects of the Invention As described above, according to the present invention, instead of bonding the skirt portions of two masks mainly on their surfaces, the skirt portion of the mask and the through hole provided in the insulating material are bonded together through the insulating material. Since it has a fixing structure, it is possible to provide a mask focusing type color picture tube having a highly accurate mask insulation support fixing structure regardless of the thickness of the adhesive used for fixing.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing a conventional color picture tube, FIG. 2 is a schematic diagram showing a mask focusing type color picture tube,
Figure 3 is an enlarged view showing the vicinity of the screen in Figure 1;
Figure 4 is an enlarged view showing the vicinity of the screen in Figure 2;
FIG. 5 is a schematic enlarged view showing a general mask support and fixing structure of a conventional color picture tube, FIG. 6 is a schematic enlarged view showing a mask support and fixing structure of a mask focusing type color picture tube, and FIGS. The figure is a schematic enlarged view of main parts showing an embodiment of the present invention. 1, 4... Electron gun, 2, 8, 25... Shadow mask, 3, 7... Screen, 5, 31, 41
...Electron gun side mask electrode: Mg, 6, 32, 45
...Screen side mask electrode: Ms, 9, 17,
18...Mask beam through hole, 10-12, 19-
21...Electron beam, 13-15, 22-24...
...Fluorescent material, 16, 28, 29...Panel, 26...
...Shadow mask skirt part, 27, 30... Frame, 33, 43... Insulator between Mg-Ms, 3
4...Mg effective surface, 35...Ms effective surface, 36...
Ms skirt part, 37...Mg skirt outer surface, 38
...Mg side surface of the insulator, 39...Ms side surface of the insulator, 40...Ms skirt inner surface, 42...Mg skirt part through hole, 44...insulator through hole, 46...
Ms skirt part through hole, 47... Insulating filler for fixing the mask, 48... Insulating screw.

Claims (1)

[Claims] 1 It has at least an electron gun, two mask electrodes fixed relatively to each other through an insulator, and a screen made of phosphors of three colors, and at least one of the mask electrodes has a In a mask focusing type color picture tube to which a voltage different from the applied voltage is applied, a through hole is provided in the skirt portion of the mask electrode and the insulator, and a through hole between the through hole in the skirt portion and the through hole in the insulator is provided. A mask focusing type color picture tube, characterized in that the two mask electrodes are fixed relatively to each other by at least partially overlapping each other and interposing an insulator to the overlapping through holes.