JP2001338598A - Fluorescent character display tube - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize a fluorescent character display tube that has a face plate of half-mirror state on the entire surface, makes the bonded part invisible from the outside in the form of a frame, and a higher level of electrostatic shielding, electron diffusion and heat radiation effect. SOLUTION: The half-mirror state is obtained by forming an aluminum film 52 on the entire back side of a face plate 51. Since other aluminum films 641 and 642 are formed separately between the aluminum film 52 and the face plate 51, change in color of the aluminum film 52 caused by sealing adhesive glass 63 cannot be seen through the face plate 51. Since the sealing adhesive glass 63 is filled in a hole 643 of the aluminum films 642 and 52, the face plate 51 adheres to a side plate 62 surely. A contact lead 71 is brought into pressure contact with the aluminum film 52 at a position of the aluminum film 642.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluorescent display tube in which a half mirror is formed on a face plate.

[0002]

2. Description of the Related Art FIG. 4 shows a conventional fluorescent display tube.
(A) is a perspective view (partially sectional view) of the fluorescent display tube,
FIG. 4B is a cross-sectional view taken along the line XX of FIG. Reference numeral 11 denotes a glass anode-side substrate on which an anode electrode 12 coated with a phosphor is formed. On the anode electrode 12, a grid 13 and a filament 14 are arranged at predetermined intervals. Reference numeral 21 denotes a glass face plate on which a chromium film 22 is formed on the back surface in the vacuum vessel. 31 and 32 are side plates of glass.
Anode-side substrate 11, face plate 21, side plate 3
1, 32 are bonded by sealing glass 33, 34,
It constitutes a vacuum container. It is known that the chromium film 22 has both an electrostatic shielding or electron diffusion function and a function of an external light reflection preventing filter. (For example, see Japanese Utility Model Laid-Open No. 55-108646)

[0003]

Since chromium used for the chromium film 22 of the conventional fluorescent display tube is a harmful substance, handling and processing of chromium in the process of manufacturing the fluorescent display tube is troublesome, and the burden is increased. Large, the manufacturing process becomes complicated, and the manufacturing cost increases. Further, since chromium is an expensive material, the cost of the fluorescent display tube increases in terms of material cost. Also, when disposing the device equipped with the fluorescent display tube, chromium treatment becomes a problem.

The chrome film 22 of the conventional fluorescent display tube is shown in FIG.
As shown in (b), it is formed only in the vacuum vessel on the back surface of the face plate 21, and is not formed between the sealing glass 33 and the face plate 21. Therefore, when the face plate 21 is viewed from the outside of the fluorescent display tube, the bonding portion of the sealing glass 33 appears as a frame around the chrome film 22. As a result, the display portion of the fluorescent display tube looks smaller than it actually looks because it is surrounded by the frame. Further, the chromium film 22 changes color from blue to green due to overheating during the manufacturing process of the fluorescent display tube. Therefore, when the appearance of a device such as an audio device or a video device equipped with the fluorescent display tube has a metallic tone, the The tendency is remarkable, and color harmony with those devices cannot be taken.

The present invention solves these problems of the chromium film and provides a film which is less expensive than chromium, is superior in optical, electrical, or heat dissipation, and has an electrostatic shielding or electron diffusion function. The purpose is to realize a fluorescent display tube that can increase the contrast between the illuminated part and the non-illuminated part without forming parts inside the fluorescent display tube that can be seen through, and can be designed in a metallic tone. I do.

[0006]

A fluorescent display tube according to the present invention comprises a vacuum vessel comprising a face plate, an anode-side substrate and a side plate, and a filament provided between the face plate and the anode-side substrate. At
An aluminum film for forming a half mirror is formed on the entire back surface of the face plate. The fluorescent display tube of the present invention is the fluorescent display tube, wherein the aluminum for forming a half mirror is provided between the face plate and the aluminum film for forming the half mirror, or between the aluminum film for forming the half mirror and the sealing glass. An aluminum film different from the film is formed. In the fluorescent display tube of the present invention, a part of the another aluminum film extends inside the fluorescent display tube. In the fluorescent display tube of the present invention, a hole filled with sealing glass is formed in the another aluminum film and the aluminum film for forming a half mirror. In the fluorescent display tube of the present invention, a window through which the getter can be visually recognized from the outside of the face plate when the fluorescent display tube is assembled is formed in the aluminum film for forming the half mirror. The fluorescent display tube of the present invention is a fluorescent display tube including a face plate, a vacuum vessel including an anode-side substrate and a side plate, and a filament provided between the face plate and the anode-side substrate. An opaque aluminum film is formed except for a window corresponding to a display portion or a window corresponding to an anode electrode, and an aluminum film for forming a half mirror is formed in the window.

[0007]

FIG. 1 shows a structure of a fluorescent display tube according to an embodiment of the present invention. FIG. 1A is a perspective view (partially sectional view) of the fluorescent display tube, and FIG.
(A) is a cross-sectional view taken along the line YY. Reference numeral 41 denotes a glass anode-side substrate, which is an anode electrode 42 coated with a phosphor.
Are formed. On the anode electrode 42, a grid 43 and a filament 44 are arranged at predetermined intervals. Reference numeral 51 denotes a glass face plate, and the aluminum film 5 is formed on the entire back surface as shown in FIG.
2 are formed. 61 and 62 are side plates of glass. The anode-side substrate 41, the face plate 51, and the side plates 61 and 62 are adhered by sealing glasses 63 and 64 to form a vacuum container. The aluminum film 52
When the film thickness becomes about 500 °, the film becomes transparent. The present invention pays attention to this point, and
By adjusting the film thickness, a half mirror is formed by the aluminum film 52 and the face plate 51. The aluminum film 52 for forming the half mirror
Uses aluminum, which is a conductive material, and thus has both functions of electrostatic shielding and electron diffusion.

If the fluorescent display tube is not provided with the aluminum film 52, the internal components will be seen through. In particular, the portion of the phosphor is conspicuous white. For this reason, the internal components are visible when the light is not lit, which makes it hard to see. In addition, at the time of lighting, external light is reflected from internal components such as a phosphor to lower contrast. On the other hand, if the film thickness is too thick, the light emission of the phosphor becomes invisible during lighting. Therefore, the present invention blocks a considerable part of the external light with the aluminum film 52, reduces reflection by components inside the fluorescent display tube, improves the contrast, and does not impair the visibility at the time of lighting. The device was devised so that the interior was almost invisible when lit.

The thickness of the aluminum film 52 is 100 to 5
The range may be 00 °, but the range of 200 to 300 ° is optimal. When the film thickness is 200 to 300 °, the transmittance of the aluminum film 52 is about 15 to 10%.
If the transmittance exceeds 20%, internal components and the like become too visible. When the film thickness is 100 ° or more, there is no particular problem since the electric resistance becomes several Ω or less (the film thickness is
When the thickness is less than 0 °, the electrical resistance increases as the film thickness decreases.) Since the aluminum film 52 is formed on the entire back surface of the face plate 51, the entire surface of the face plate 51 becomes a mirror surface,
No frame-like frame is visible around 1. Moreover, since the aluminum film 52 is formed of aluminum, it exhibits a metallic color.

Next, various characteristics of the aluminum film 52 will be described. When the film for forming the half mirror is made of aluminum and chromium, a film having a transmittance of 10% has a thickness of about 140 ° for chromium and about 300 ° for aluminum. That is, when the transmittance of the film for forming the half mirror is the same, the film thickness of aluminum can be larger than that of chromium. On the other hand, the electrical resistance of aluminum is a fraction of that of chromium. Considering these two characteristics, when the transmittance of the film for forming a half mirror is the same, the electrical resistance of the film is much smaller in aluminum than in chromium. Therefore, it can be seen that the aluminum film 52 of the present invention is superior to chromium as a film for electrostatic shielding or electron diffusion.

Although the aluminum film 52 also contributes to the heat radiation of the fluorescent display tube, the heat conductivity of aluminum is several times larger than that of chromium. ing. As for heat dissipation, since the aluminum film 52 of the present invention is exposed outside the fluorescent display tube, a greater heat dissipation effect can be obtained than in the conventional fluorescent display tube.

FIG. 2 is a plan view for explaining a fluorescent display tube according to another embodiment of the present invention, and a sectional view of the fluorescent display tube. FIG. 2A corresponds to a plan view of the face plate 51 of FIG. In FIG. 1, when lead borosilicate glass is used for the sealing glass 63, the aluminum film 52 is formed by a chemical reaction of the lead borosilicate glass.
Turns black. When the thickness of the aluminum film 52 is small, the blackening extends to the face plate 51 side,
The blackened portion may look like a frame around the display portion 54 like 53. In the present embodiment, even if the blackening occurs, the blackened portion is devised so as not to appear on the face plate 51 side unlike 53.

FIG. 2B is a sectional view of the fluorescent display tube of the present embodiment. In this embodiment, an aluminum film 641 having a thickness of 0.8 μm or more is provided between the aluminum film 52 and the face plate 51. Aluminum film 641
Are formed on the entire periphery of the display portion 54. 642
Indicates an aluminum film 641 on the side plate 62 side. The aluminum film 642 is wider than the other portions of the aluminum film 641 and extends inside the fluorescent display tube more than the width of the sealing glass 63. By providing the aluminum film 641, even if the aluminum film 52 is blackened by the sealing glass 63, the blackening is performed by the aluminum film 64.
1, 642 does not reach the face plate 51 side. One end of the contact lead 71 is
The extended portion 42 is in pressure contact with the aluminum film 52. Even if the aluminum film 52 is damaged by the tip of the contact lead 71, the aluminum film 6
42 covers the damage, the aluminum film 52
The electrical connection between the contact lead 71 and the contact lead 71 is not impaired, and the connection reliability is improved. The other end of the contact lead 71 is attached to a filament support member or the like, and applies a predetermined potential such as a filament potential to the aluminum film 52.

FIG. 2C is a sectional view of an embodiment of the aluminum films 641 and 642 in FIG. 2B, and shows only the aluminum film 642. Aluminum films 642, 52
Are formed with a plurality of holes 643 in the bonding portion between the face plate 51 and the side plate 62. In the hole 643,
At the time of sealing, the sealing glass 63 is filled to reinforce the adhesion between the face plate 51 and the side plate 62. The hole 643 may have an arbitrary shape such as a circular shape or a stripe shape. Although the aluminum films 641 and 642 of FIGS. 2B and 2C are formed between the aluminum film 52 and the face plate 51, they may be formed between the aluminum film 52 and the sealing glass 63. it can. In the case of FIGS. 2B and 2C, the width of the aluminum film 641 is increased only at the side plate 62 side (only the aluminum film 642), but the other portions are also as wide as the aluminum film 642. May be widened.

In the case of FIGS. 2B and 2C,
Although the aluminum film 52 and the aluminum film 641 are laminated, the display portion 5 is formed on the entire surface of the face plate 51.
4 or an opaque aluminum film corresponding to the aluminum film 641 except for the window portion corresponding to the anode electrode (42 in FIG. 1), and the window portion corresponds to the aluminum film 52 for forming a half mirror. May be formed.

FIG. 3 shows an embodiment of the aluminum film 52 of the present invention. FIG. 3A is a plan view and FIG.
3A is a cross-sectional view taken along the line ZZ in FIG. On the rear surface of the face plate 51, an aluminum film 52 is formed on the entire surface except for the non-film portion 82. The non-film portion 82 is formed in a window of the aluminum film 52 at a position where the evaporable getter 81 can be visually recognized from outside the face plate 51 as shown in FIG. When the fluorescent display tube is assembled, the position of the getter 81 can be confirmed from outside the face plate 51 when the non-film portion 82 is assembled, which is convenient for the assembly. After the assembly, the value of the getter material of the getter 81 is evaporated by high frequency heating or the like, so that the non-film portion 82
Is covered with a value (metal film) and becomes a metallic mirror-like surface. That is, after the completion of the fluorescent display tube, the non-film portion 82
Is also covered by the value, forming a mirror surface.

[0017]

The present invention provides a film for forming a half mirror,
Since it can be formed of aluminum, it is not necessary to use harmful chromium unlike a conventional fluorescent display tube. Aluminum is a material used for the anode electrode and the internal wiring of the fluorescent display tube, so that the half mirror forming film can be formed by the same method as the anode electrode and the wiring. Therefore, the manufacture of the fluorescent display tube becomes easy, and it is not necessary to treat chromium in the manufacturing process.
Manufacturing costs can be reduced. Further, since aluminum is a cheaper material than chromium, the manufacturing cost of the fluorescent display tube can be reduced. Further, there is no problem such as chromium treatment after disposing of the device equipped with the fluorescent display tube.

Since the half mirror forming film of the present invention is formed on the entire back surface including the sealing portion of the face plate, a frame-like frame can be seen at the bonding portion like a conventional fluorescent display tube. The display does not appear small. The half mirror forming film is
Because it is aluminum, it has a metallic color. Therefore, when a fluorescent display tube is mounted on a device such as an acoustic device or a video device having a metallic appearance, the color tone matches well with those colors.

Since aluminum has lower electric resistance and higher thermal conductivity than chromium, the film for forming a half mirror according to the present invention has lower electric resistance and higher heat radiation effect than chromium. Therefore, the film for forming a half mirror of the present invention has a more uniform electrostatic shielding effect and electron diffusion effect over the entire surface, and the display quality of the fluorescent display tube is improved. In addition, the half mirror forming film of the present invention is formed of a material having a high heat radiation effect and is exposed outside the fluorescent display tube, so that a greater heat radiation effect can be obtained. it can.

According to the present invention, since an aluminum film is formed separately from the half mirror forming film on the bonding portion of the face plate, lead borosilicate glass is used as the sealing glass.
Even if the adhesive portion of the half mirror forming film is blackened, the blackening does not reach the face plate side. Further, since the contact lead is in pressure contact with the half mirror forming film at the portion of the another aluminum film, even if the half mirror forming film is damaged by the contact, the another aluminum film is not damaged. Since the damage is covered, the electrical connection between the contact lead and the film for forming the half mirror is not impaired.

Further, since a hole filled with sealing glass is formed in the sealing portion between the half mirror forming film and the another aluminum film, the face plate and the side plate can be securely bonded. .

[Brief description of the drawings]

FIG. 1 is a perspective view and a sectional view of a fluorescent display tube according to an embodiment of the present invention.

FIG. 2 is a plan view and a cross-sectional view of a fluorescent display tube according to another embodiment of the present invention.

FIG. 3 is a plan view and a sectional view of an embodiment of the present invention.

FIG. 4 is a perspective view and a sectional view of a conventional fluorescent display tube.

[Explanation of symbols]

 41 Anode substrate of glass 42 Anode electrode coated with phosphor 43 Grid 44 Filament 51 Face plate of glass 52 Aluminum film 53 Blackened portion 54 Display portion 61, 62 Side plate of glass 63, 64 Sealing glass 641, 642 Aluminum film 643 hole 71 contact lead 81 getter 82 non-film part

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Hiroshi Saito 629 Futaba Electronics Co., Ltd., Oshiba, Mobara City, Chiba Prefecture 72) Inventor Shinya Osamu, Futaba Electronics Industry Co., Ltd. 629, Oshiba, Mobara City, Chiba Prefecture Mobara-shi Oshiba 629 Futaba Electronics Co., Ltd.In-house (72) Inventor Junichiro Kogure EH09

Claims (6)

[Claims] 1. A fluorescent display tube comprising a vacuum vessel comprising a face plate, an anode-side substrate and a side plate, and a filament provided between the face plate and the anode-side substrate, for forming a half mirror on the entire back surface of the face plate. A fluorescent display tube, wherein an aluminum film is formed. 2. The fluorescent display tube according to claim 1, wherein
Make sure that an aluminum film different from the aluminum film for forming the half mirror is formed between the face plate and the aluminum film for forming the half mirror, or between the aluminum film for forming the half mirror and the sealing glass. Characteristic fluorescent display tube. 3. The fluorescent display tube according to claim 2, wherein
A part of the another aluminum film extends inside the fluorescent display tube. 4. The fluorescent display tube according to claim 2, wherein
A fluorescent display tube, wherein the another aluminum film and the aluminum film for forming a half mirror are formed with holes filled with sealing glass. 5. The fluorescent display tube according to claim 1, wherein
A fluorescent display tube characterized in that a window through which a getter can be visually recognized from the outside of a face plate when the fluorescent display tube is assembled is formed on an aluminum film for forming a half mirror. 6. A fluorescent display tube provided with a vacuum vessel comprising a face plate, an anode-side substrate and a side plate, and a filament provided between the face plate and the anode-side substrate. A fluorescent display tube, wherein an opaque aluminum film is formed except for a corresponding window or a window corresponding to an anode electrode, and an aluminum film for forming a half mirror is formed in the window. .