JPS5933148Y2 - color picture tube - Google Patents

Description

[Detailed description of the invention] The present invention relates to a color picture tube, and in particular, the electron beam movement of the color picture tube is reduced by attaching an electron shield and a casing or an inner shield to a mask frame that supports a shadow mask. It's about structure.

For example, the panel portion of a color picture tube incorporating an electron shield has a structure as shown in FIG.

That is, a panel 2 has a fluorescent surface 1 on the inner surface of which phosphor layers emitting light in red, green, and blue colors are regularly formed, and a panel 2 is embedded at a predetermined position on the inner surface of a side wall 3 of the panel 2. A frame support 7 made of a bimetallic material 5 and a spring material 6 is attached to the panel pin 4, a first side 8□ in the tube axis direction to which the bimetallic material 5 is fixed, and a side (not shown) perpendicular to this first side 8□. A mask frame 8 consists of a second side 82 facing the electron gun, and a skirt portion 9□ is fixed to the outer wall of the first side 8□ on the fluorescent surface 1 side, and the effective portion 92 is attached to the fluorescent surface 1. A shadow mask 9 is disposed at a predetermined distance from the electron beam passage hole 9a, and an undesired electron beam 10□, 10 from the electron gun is disposed at a second side 8° on the electron gun side. Block out ゜,
An electron shield 11 that allows only effective electron beams 103 and 104 to strike a predetermined phosphor layer of the phosphor surface 1 through an electron beam passage hole 9a, and a second side 8° between the electron shield 11 and the second side. It is composed of a locking spring 12.

When operating a color picture tube having such a structure, electron beams other than the effective electron beams io3 and 104 impinge on the effective part 92 of the shadow mask, expand this effective part 9°, and make the central part fluorescent. The impact position on the fluorescent surface 1 of the electron beams 103 and 104 projected toward the surface 1 side and passing through the same electron beam passage hole 9a moves, and in the case of a 14-inch tube, the point 22 of the curve 21 in FIG. The amount of beam movement is generated as follows.

This point 22 differs depending on the type of pipe, but is approximately 10 minutes after operation.

Next, the temperature of this effective part 9□ moves to the mask frame 8 via the mask skirt part 9, and this mask frame 8
At the same time, the bimetallic material 5 is also heated, and the effective portion 9□ is brought closer to the fluorescent surface 1 as a whole.
The impact position of the electron beams 103 and 104 on the phosphor surface 1 moves, passing through the point 23 where the amount of beam movement is zero on the curve 21 in FIG. Stabilize.

In this case, the electron shield 11 and the mask frame 8
The second side 8□ of the electron gun side is only locked with a spring 12, etc., and undesired electron beams 10□,
Even if the electron shield is heated by, for example, 10 degrees, the heat is not transferred to the mask frame 8, and therefore the heating of the mask frame 8 and bimetal material 5 is only transferred from the effective portion 92 through the mask skirt portion 9□. In particular, it takes a considerable amount of time after operation to heat up the bimetal material 5, and the old electron shield 11 also acts as a heat sink, so the beam movement after point 24 is stable at about 30μ. Become.

This phenomenon is caused by clip 1 in addition to electron shield 11.
This becomes even more noticeable when an internal magnetic shield (not shown) is provided.

As a result, the amount of beam movement on the phosphor surface fluctuates as shown in curve 21, and the landing margin for the electron beam on the phosphor layer is extremely small, resulting in color shift and poor white balance, resulting in poor quality of the color picture tube. There were drawbacks that made it worse.

The present invention was developed in view of the above-mentioned drawbacks of the conventional method, and even when an electron shield and/or inner shield is provided, the bimetallic material is rapidly heated, and in particular, the amount of beam movement that is almost stable during operation is reduced. The purpose is to provide a color picture tube that can

Next, one embodiment of the present invention will be described with reference to FIGS. 3 to 6.

That is, the color picture tube includes a panel 32 having a fluorescent surface 31 on the inner surface of which phosphor layers emitting red, green, and blue light are regularly formed, and a side wall 33 of this panel 32 located at a predetermined inner surface. A frame support 37 made of a bimetal material 35 and a spring material 36 is attached to the implanted panel pin 34, a first side 38□ in the tube axis direction to which the bimetal material 35 is fixed, and a funnel 43 to the side wall portion 33. articulated neck 4
The first side 38 is disposed opposite to the electron gun 45 installed in the
Mask frame 3 consisting of □ and a second side 382 perpendicular to
8, and a skirt portion 39□ is fixed to the outer wall of the first side 38□ on the fluorescent surface 1 side, such that the effective portion 39□ connected to this skirt portion 39□ has a predetermined distance from the fluorescent surface 31. A shadow mask 39 with an electron beam passing hole 39a formed therein and a second side 38□ on the electron gun 45 side are arranged to prevent unwanted electrons from the electron beam 40 from the electron gun 45. an electron shield 41 that blocks the beam 40□ and makes only the effective electron beam 402 impinge on a predetermined phosphor layer of the phosphor surface 31 through the electron beam passage hole 39a;
The configuration of the electron shield 41 and the spring 42 that locks the second side 38° is almost the same as the conventional one, but in this embodiment, the bimetal material 35 of the electron shield 41 is An opening 41a is formed at a position opposite to the second side 382 of the mask frame 38 corresponding to the part to which the mask frame 38 is fixed, so as to expose the surface of the second side 382 on the electron gun 45 side. , electron gun 4
The electron beam 403 from No. 5 is made to directly impinge on the mask frame 38 to locally heat this portion.

When operating a color picture tube having such a structure, electron beams other than the effective electron beam 402 impinge on the effective part 392 of the shadow mask, expand this effective part 39°, and turn the central part into the fluorescent surface 31. Fluorescent surface 31 of electron beam 402 which is projected to the side and passes through the same electron beam passage hole 39a.
The upper firing position moves, and in the case of a 14-inch tube, a beam movement amount as shown at point 52 of curve 51 in FIG. 6 is generated.

A beam movement amount such as this point 52 is generated.

Although this point 52 differs depending on the type of pipe, it is approximately 10 minutes after operation.

Next, the temperature of this effective part 392 is determined by the temperature of the mask skirt part 39.
While the mask frame 38 is expanded through □, the bimetal material 35 is also heated, but in this embodiment, the electron beam 403 directly targets a portion of the mask frame 38, particularly a portion corresponding to the bimetal material 35, through the opening 41a of the electron shield 41. Since direct heating is performed, the entire effective portion 39° can be brought closer to the fluorescent surface 31 side faster than before.
The point 53 of the beam movement amount of zero on the curve 51 in FIG.
It is stable at position 4, and the amount of beam movement at this time can be reduced by approximately 10μ compared to conventional methods, allowing more margin for the electron beam to land on the phosphor layer, making it possible to create a color picture tube with good color shift and white balance. I was able to get it.

In the above embodiments, a color picture tube using only an electron shield was described, but the same applies to other tubes equipped with an inner shield, or those equipped with an electron shield and an inner shield at the same time, and the opening also prevents unwanted electron beams. Of course, the notch may be used as long as it does not impinge on the fluorescent surface.

[Brief explanation of the drawing]

Fig. 1 is an enlarged cross-sectional view of the main part of a conventional color picture tube, Fig. 2 is a curve diagram showing changes in the amount of beam movement of the color picture tube shown in Fig. 1 over time, and Figs. 3 is a cross-sectional view, FIG. 4 is a plan view of the panel section viewed from the electron gun side, and FIG. 5 is a diagram showing the color picture tube of the invention.
FIG. 6 is a cross-sectional view taken along the line -A' and viewed in the direction of the arrow, and a curve diagram showing changes in the amount of beam movement over time. 1.31... Fluorescent surface, 2,32... Panel, 5°3
5... Bimetal material, 8, 38... Mask frame, 9.39... Shadow mask, 11.41... Electron shield, 41a... Opening, 12, 42
···spring.

Claims (1)

[Scope of utility model registration request] A shadow mask, a mask frame that supports the shadow mask, a frame support including a bimetallic material that supports the mask frame on panel pins, and a collar in which an electron shield and/or an inner shield are provided on the electron gun side of the mask frame. A color picture tube characterized in that the electron shield and/or the inner shield is provided with an opening or a notch so as to expose the electron gun side of the mask frame corresponding to the bimetal material.