JPH1092351A - Fluorescent display tube - Google Patents

Abstract

PROBLEM TO BE SOLVED: To show various colors with a fluorescent display tube not to be reduced in life. SOLUTION: Annular anodes 4 with the open centers are formed at openings in preset areas in an insulating layer 3 on a glass substrate 1. On the glass substrate 1 in areas encircled by the anodes 4, optical filters 11 formed of pigment, e.g. are formed. Emission parts 5 formed of zinc oxide based fluorescence are formed on the optical filters 11 in the condition that the ends or their vicinities are connected to the anodes 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a flat light emitting fluorescent display tube in which a display is viewed from a glass substrate side.

[0002]

2. Description of the Related Art A fluorescent display tube is an electron tube that displays a desired pattern by causing thermal electrons emitted from a cathode called a filament to collide with a phosphor and emit light in a vacuum vessel at least one of which is transparent. The phosphor is applied in the form of a pattern to be displayed on the anode. Usually, a triode structure having a grid for controlling the function of electrons is most often used.

FIG. 4 is a sectional view showing a structure of a conventional fluorescent display tube. As shown in FIG. 4, a wiring layer 2 is formed on a glass substrate 1, and an insulating layer 3 is formed on the wiring layer 2. An anode electrode (anode) 4b is formed at a predetermined position on the insulating layer 3, and the anode electrode 4b is connected to a predetermined position of the wiring layer 2 through a through hole 3a formed in the insulating layer 3. Have been. In addition, the anode electrode 4
A phosphor 5 is formed on b, a grid 6 is disposed on the phosphor 5, and a filament 7 is disposed thereon.

On the other hand, a spacer glass 8 is disposed at an end of the glass substrate 1, and a transparent windshield 9 is disposed thereon so as to face the glass substrate 1. Glass substrate 1
The spacer glass 8 and the spacer glass 8 and the windshield 9 are respectively bonded and fixed by a glass frit 10 to form an envelope. Although not shown, a lead is provided through a glass frit 10 at a contact portion between the spacer glass 8 and the glass substrate 1, and the lead is connected to the wiring layer 2.

The above-described fluorescent display tube has a configuration in which light emitted from the phosphor 5 is viewed through the windshield 9. Here, in such a fluorescent display tube, when an attempt is made to cope with multicoloring, a method using phosphors of different emission colors,
There is a method of converting the emission color of the phosphor using a color filter. In the method using phosphors of different emission colors, Zn
S: A sulfide phosphor such as Ag is added with In ₂ O ₃ for imparting conductivity to obtain various emission colors. However, when a sulfide phosphor is used, there is a problem in that, when excited by an electron beam, its constituent substances are scattered, thereby deteriorating the filament and shortening its life.

On the other hand, in the method using a color filter, it is easy to cope with multicoloring, and there is no problem of deterioration of the cathode since mainly an oxide-based phosphor can be used.
However, a color filter cannot be formed on the phosphor. Therefore, in the above-described fluorescent display tube, a color filter is formed on the front surface or the back surface of the windshield. However, in this case, since the light emitting portion (phosphor layer) and the color filter are separated from each other, a shift easily occurs depending on a viewing angle, and it is difficult to color a fine pattern.

On the other hand, in the flat emission type fluorescent display tube shown in FIG. 5, since the color filter 11b is formed on the surface of the glass substrate 1 where the emitted light is viewed, no color shift occurs and the grid is formed. Since the electrode built-in components such as 6 and the filament 7 cannot be seen, the display becomes clearer. As shown in FIG. 5, in the flat emission type fluorescent display tube, a color filter 11b is formed at a predetermined position on the glass substrate 1, and a translucent anode electrode 4c and a phosphor 5 are formed thereon. As the translucent anode electrode 4c, for example, ITO or the like may be used. Although not shown, the anode electrode 4c is connected to a wiring layer.
Other symbols are the same as those in FIG.

[0008]

By the way, in the above-mentioned flat emission type fluorescent display tube, the color filter 11b is formed by using colored glass frit or the color filter 11b is formed on the glass substrate 1 at the position where the phosphor 5 is formed. The color filter 11b is formed by directly coloring. In addition, the glass substrate 1 can be colored directly by substituting and coloring the alkali ions in the glass with silver or copper ions. However, there is a problem in that these colors have limitations in colors that can be expressed, such as the inability to produce blue, and that they cannot be completely adapted to multicoloring.

[0009] In contrast, if pigments are used for the color filters 11b, more various colors can be expressed. However, there is a problem that the light-transmitting anode electrode 4c cannot be formed uniformly on the color filter 11b made of pigment. The surface of the color filter 11b composed of a pigment does not have flatness, and it is very difficult to form a uniform electrode thereon. As described above, in the conventional technique, in the multi-color display of the fluorescent display tube, there is a limit to the colors that can be expressed in an attempt to extend the life, and there is a problem that more various colors cannot be expressed.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to make it possible to express various colors on a fluorescent display tube without shortening the life.

[0011]

A fluorescent display tube according to the present invention comprises: an optical filter made of, for example, a pigment disposed in an opening formed in a predetermined region of an insulating layer on a glass substrate constituting an envelope; A light-emitting portion made of, for example, a zinc oxide-based phosphor is provided on the light-emitting portion. Under the optical filter, an anode electrode is provided which is in contact with the light emitting unit through a hole partially opened in the optical filter, so that light emitted from the light emitting unit is emitted from the glass substrate side through the optical filter. I made it. Therefore, the driving potential applied to the anode electrode is also applied to the light emitting unit. Then, the light emitted from the light emitting portion by applying the driving potential to the anode electrode passes through the optical filter and is observed from the glass substrate side.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. Embodiment 1 FIG. FIG. 1 is a sectional view and a plan view showing a partial configuration of a fluorescent display tube according to the first embodiment of the present invention. As shown in FIG. 1A, a color filter (optical filter) 11 made of a pigment is formed at a predetermined position of the glass substrate 1 where the insulating layer 3 is opened. Note that the insulating layer 3 blocks light. Further, an anode electrode 4 is formed on the glass substrate 1 so as to surround the color filter 11. The anode electrode 4 is made of, for example, a metal such as aluminum.

Then, a phosphor (light emitting portion) 5 is formed on the color filter 11 with its end contacting the anode electrode 4. The phosphor 5 is made of a ZnO: Zn phosphor or the like. If a plurality of these color filters 11, anode electrodes 4, and phosphors 5 are arranged in a matrix as one dot and used, a dot matrix type fluorescent display tube can be constructed. FIG. 1B is a plan view showing the shape of the anode electrode 4 in a partial area where the phosphor 5 is formed. The anode electrode 4 is formed so as to surround the color filter 11. Although not shown, the anode electrode 4 is connected to a wiring layer. Other symbols are the same as those in FIG.

A driving potential is applied to the phosphor 5 by contacting the anode electrode 4 at its end. Thus, the phosphor 5 emits light when the electrons emitted from the filament 7 and guided by the grid 6 enter the phosphor 5. The emitted light of the phosphor 5 passes through the color filter 11 and can be seen through the glass substrate 1. At this time, according to the first embodiment, since the anode electrode 4 is not formed on the color filter 11, unlike the related art,
Light emitted from the phosphor 5 does not pass through the anode electrode 4.

Here, it is difficult to uniformly form an electrode film made of metal or the like on the color filter 11 made of a pigment, but it is easy to form the phosphor 5. Therefore, in the first embodiment, the anode electrode 4 is formed not on the color filter 11 but on the glass substrate 1. Therefore, the anode electrode 4 can be formed stably and uniformly. According to the first embodiment, since the pigment can be used for the color filter 11 as described above, it is possible to obtain a desired spectral characteristic for the display color of the fluorescent display tube. Further, according to the first embodiment, it is not necessary to use a sulfide phosphor that causes deterioration of the filament 7 in order to enable multicolor display, so that the life of the fluorescent display tube is not shortened.

Embodiment 2 Hereinafter, a fluorescent display tube according to the second embodiment of the present invention will be described. FIG.
FIG. 7 is a cross-sectional view and a plan view showing a partial configuration of a fluorescent display tube according to the second embodiment. In the second embodiment, the contact area between the phosphor 5 and the anode electrode 4a is made larger. In addition, other symbols are shown in FIG.
Is the same as As shown in FIG. 2A, the phosphor 5
At the center, the hole passes through the hole 12 at the center of the color filter 11a, and is in contact with the center of the anode electrode 4a. In addition, as in the first embodiment, the peripheral end of the phosphor 5 is in contact with the peripheral part of the anode electrode 4a.

As described above, according to the second embodiment, since the phosphor 5 and the anode electrode 4a are in contact with each other over a larger area, the luminous efficiency can be further increased. Also in the second embodiment, similar to the first embodiment, a pigment can be used for the color filter 11a, so that a desired spectral characteristic can be obtained for the display color of the fluorescent display tube. Further, since it is not necessary to use a sulfide phosphor that causes the deterioration of the filament 7 in order to enable multicolor display, the deterioration of the filament 7 does not occur and the life of the fluorescent display tube is not shortened.

Embodiment 3 FIG. 3 is a plan view showing another embodiment of the present invention. In the above embodiment, the anode electrode is formed so as to surround the region where the phosphor is formed. However, the present invention is not limited to this. As shown in FIG. 3A, a color filter 31 is formed on the entire surface of a region where a phosphor (not shown) is formed, and an anode electrode 32 is formed under the color filter 31 so as to pass through the center of the region where the phosphor is formed. May be formed. In this case, the area concealed by the anode electrode 32 with respect to the area in front of the color filter 31 only needs to be equal to or less than a predetermined area so that the emission light of the phosphor passes by a predetermined amount or more. Then, the anode electrode 32 and the phosphor are in contact with each other through a hole 33 formed at a predetermined position of the color filter 31.

Further, as shown in FIG. 3B, an anode electrode 32a may be arranged below the color filter 31 to make contact with a phosphor (not shown) via the hole 33a. As described above, the state where the anode electrode is formed in a part of the region through which the emission light of the phosphor passes, and the phosphor and the anode are formed through the hole formed in the color filter in the region above the anode electrode Even if the electrodes are in contact,
It has the same effects as the first and second embodiments.

[0020]

As described above, according to the present invention, there is provided an optical filter made of, for example, a pigment disposed in an opening formed in a predetermined region of an insulating layer on a glass substrate constituting an envelope, and And a light-emitting portion made of, for example, a zinc oxide-based phosphor. Under the optical filter, an anode electrode is provided which is in contact with the light emitting unit through a hole partially opened in the optical filter, so that light emitted from the light emitting unit is emitted from the glass substrate side through the optical filter. I made it. Therefore, the driving potential applied to the anode electrode is also applied to the light emitting unit. Then, the light emitted from the light emitting portion by applying the driving potential to the anode electrode passes through the optical filter and is observed from the glass substrate side. As a result, according to the present invention, various colors can be expressed by the fluorescent display tube without using a sulfide-based phosphor that shortens the life of the fluorescent display tube. In addition, by appropriately setting the transmitted light spectral characteristics of the optical filter, various colors can be expressed by the fluorescent display tube.

[Brief description of the drawings]

FIG. 1 is a sectional view and a plan view showing a partial configuration of a fluorescent display tube according to a first embodiment of the present invention.

FIGS. 2A and 2B are a cross-sectional view and a plan view illustrating a partial configuration of a fluorescent display tube in Embodiment 2. FIGS.

FIGS. 3A and 3B are a cross-sectional view and a plan view illustrating a partial configuration of a fluorescent display tube in Embodiment 3. FIGS.

FIG. 4 is a cross-sectional view showing a configuration of a conventional fluorescent display tube.

FIG. 5 is a cross-sectional view showing a configuration of a flat emission type fluorescent display tube.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Glass substrate, 3 ... Insulating layer, 4 ... Anode electrode, 5 ...
Phosphor, 6 grid, 7 filament, 8 spacer glass, 9 windshield, 10 glass frit, 11 color filter.

Claims (3)

[Claims] An enclosure that includes a glass substrate and has an inside that is evacuated, an insulating layer disposed on the surface of the glass substrate, and an opening that is opened in a predetermined region of the insulating layer on the glass substrate. An optical filter arranged, a light emitting portion made of a phosphor arranged on the optical filter, and an emission filter arranged in a predetermined area below the optical filter, and the light emission through a hole partially opened in the optical filter. An anode electrode in contact with the light-emitting portion; a filament disposed above the light-emitting portion for emitting electrons; and an electron-emitting portion disposed between the filament and the light-emitting portion to extract electrons emitted from the filament and collide with the light-emitting portion. And a wiring layer disposed in contact with the anode electrode on the glass substrate below the insulating layer, wherein the light emitted from the light emitting section is emitted from the optical filter. Fluorescent display tube, characterized in that it is emitted from the glass substrate side through the data. 2. The fluorescent display tube according to claim 1, wherein the anode electrode is disposed so as to surround a periphery of the optical filter, and the light emitting unit contacts the anode electrode at an end of the optical filter. A fluorescent display tube arranged on the top. 3. The fluorescent display tube according to claim 1, wherein the optical filter is made of a pigment.