JP2001266779A - Fluorescent display tube and its drive method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fluorescent display tube having planar grids, reducing charge-up of an insulating layer, to prevent an eclipse phenomenon of electrons and to disperse electrons emitted from filaments to anode electrodes to both sides of a linear filmament into a uniformly planar form. SOLUTION: Stripe thin film anode electrodes A1-An and stripe thin film grids G1-G7 are formed in matrix on a first substrate S1 via a thin-film insulating layer D. Opening portions are formed in the insulating layer and the grids, fluorescent materials H11-H7n are applied to the anode electrodes in the opening portions, and the grids are equal in height to or smaller than the fluorescent materials. Back electrodes B1-B9 are formed on a second substrate S2 for controlling electron emission of the filaments, and a potential gradient is provided for control voltage to be applied to the back electrodes, so as to differentiate a potential between points which are close to and far from the filaments F1, F2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a graphic type fluorescent display (VFD) using a plane grid and a driving method thereof.

[0002]

2. Description of the Related Art FIG. 11 shows a plan view and a sectional view of a part of an anode-side substrate of a fluorescent display tube using a conventional flat grid. FIGS. 11B and 11C show arrows X in FIG.
FIG. 11B is an enlarged cross-sectional view of FIG.
(C) is different in the structure of the opening. S1 is a glass substrate on the anode side and includes a plurality of striped anode electrodes A1.
To Am, and a solid insulating layer D on the anode electrodes A1 to Am, and grids G1 to G on the insulating layer D.
7 are formed. The anode electrodes A1 to Am and the grids G1 to G7 are arranged in a matrix. Square openings are formed in the grids G1 to G7 and the insulating layer D, and the phosphors H11 to H11 are formed on the anode electrodes in the openings.
H7m is applied. Anode electrodes A1 to Am, grids G1 to G7, phosphors H11 to H7m, and insulating layer D
Is a thick film formed by printing.

In the case of FIG. 11B, the height of the phosphor H21 and the height of the insulating layer D are the same, but in the case of FIG.
The phosphor H21 is formed at a position lower than the insulating layer D. The filaments not shown are grids G1 to G
7 (on the side opposite to the anode electrode).
(See JP-A-63-69354).

[0004]

Since the grid has a function of extracting electrons emitted from the filament to the anode electrode, it is necessary to arrange the grid closer to the filament than the anode electrode. In both cases of FIGS. 11B and 11C, the grids G2 and G3 correspond to the phosphors H21 and H3.
It is arranged at a position higher than 1 (closer to the filament). As a result, in the case of FIG. 11B, some of the electrons emitted from the filament to the anode electrode A1 are:
It collides with the exposed surface Ds1 of the insulating layer D and charges up. In the case of FIG. 11C, the exposed surface D of the insulating layer D
It collides with s2 and charges up.

In the cases shown in FIGS. 11B and 11C, the electrons arriving at the end of the phosphor H21 are repelled by the charged-up charges and cannot reach the phosphor H21. As a result, a portion that does not emit light occurs at the end of the phosphor H21. Phosphor H
The same applies to 31. The effect of this electron eclipse phenomenon becomes greater as the width of the anode electrode and the grid decreases and the distance between them decreases. In other words, the higher the definition, the greater the effect of the electron eclipse phenomenon and the lower the display quality.

Further, the conventional fluorescent display tube has grids G1 to G1.
Since G7 and the insulating layer D are formed of a thick film, for example, the thickness of the insulating layer D is limited to about 0.2 mm. Therefore, it is difficult to increase the definition of a thick film. Further, when the openings are formed in the grids G1 to G7, if the shape of the openings is as shown in FIG. 11A, a bridge cannot be provided in the mask for forming the openings, so that mask evaporation is practically adopted. Can not.

[0007] Further, since the filament of the fluorescent display tube is stretched at a predetermined interval, the amount of emitted electrons is different between a portion where the anode electrode is close to the filament and a portion which is far from the filament. A difference in light emission luminance (luminance unevenness) occurs. In view of these points, the present invention provides a high-definition fluorescent display tube in which charge-up of an insulating layer is small, electrons emitted from a filament are uniformly diffused in a plane, and luminance unevenness is small, and An object of the present invention is to provide a fluorescent display tube in which a grid can be formed by mask evaporation.

[0008]

A fluorescent display tube according to the present invention has a first structure in which a striped anode electrode and a striped grid are formed in a matrix with an insulating layer interposed therebetween.
A filament is stretched in the longitudinal direction of the back electrode between the substrate and the second substrate on which the striped back electrode is formed, and an opening is formed in the grid and the insulating layer where the anode electrode and the grid intersect. The phosphor is applied on the anode electrode in the opening. In the fluorescent display tube of the present invention, the grid is formed at a position where the height of the grid is substantially the same as or lower than that of the phosphor. In the fluorescent display tube of the present invention, the grid is formed of a thin film. In the fluorescent display tube of the present invention, a notch is formed in the opening of the grid. The fluorescent display tube of the present invention is provided with a means for setting a potential gradient to the filament selection voltage applied to the back electrode.

In the present invention, a filament which emits electrons is selected by applying a filament selection voltage and a filament non-selection voltage in a time division manner for each filament control group of the back electrode. In the present invention, a filament which emits electrons is selected by applying a filament selection voltage and a filament non-selection voltage to the filament in a time-division manner. The present invention relates to a filament which emits electrons by applying a filament selection voltage and a filament non-selection voltage in a time division manner to each filament control group of the back electrode, and applying a filament selection voltage and a filament non-selection voltage to the filament in a time division manner. Is selected. In the present invention, a potential gradient is provided to the filament selection voltage applied to each filament control group of the back electrode. In the present invention, a grid selection voltage is applied to a grid in a time-division manner, and a data signal is input to an anode electrode to select a phosphor to emit light.

[0010]

FIG. 1, FIG. 2 and FIG. 3 show a plan view and a sectional view of a part of a fluorescent display tube according to an embodiment of the present invention. 1A is a plan view of the first substrate portion in the direction of arrow C in FIG. 1B, and FIG. 1B is a cross-sectional view of the first substrate portion in the direction of arrow A in FIG. 1A and a cross-sectional view of a filament and a second substrate portion not shown in FIG. FIG. 2A is a cross-sectional view in the direction of arrow D in FIG.
(B) is an enlarged view of the first substrate portion of FIG. 1 (b). FIG. 3A is an enlarged view of the first substrate portion of FIG.
(b) shows another embodiment of FIG. 1 (b).

S1 is a first glass substrate, A1 to An are striped thin-film anode electrodes, H11 to H1n,.
H71 to H7n are phosphors, D is a thin film insulating layer, G1 to G7
Is a striped thin film grid having openings, F1,
F2 is a filament, B1 to B9 are striped back electrodes, S2 is a second glass substrate, and S3 is a glass side plate. Anode electrodes A1 to An and grids G1 to G7
Are arranged in a matrix with the insulating layer D interposed therebetween, and openings are formed in the portions of the grids G1 to G7 and the insulating layer D where they intersect. The anode electrodes A1 to An have phosphors H11 to H7n at portions exposed to the openings.
Has been applied. The filaments F1 and F2 are stretched in the longitudinal direction of the striped back electrodes B1 to B9.

The width of the anode electrodes A1 to An is 125 μm.
m, and the interval between the anode electrodes A1 to An is 125 μm. The diameter of the filament F1 and the filament F2 is 15 μm. The distance between the filament and the anode electrode is about 1.0 mm.

Details of the openings of the grids G1 to G7 and the insulating layer D are shown in FIGS. 2 (b) and 3 (a). FIG. 2 (b)
In the case of, the heights of the phosphors H33 and H43 and the grids G3 and G4 are the same. Also in the case of FIG. 3A, the heights of the phosphors H52 and H53 and the grid G5 are the same. In this way, by making the height of the phosphor substantially equal to that of the grid, the electrons emitted from the filament are concentrated on the phosphor, the charge-up of the insulating layer can be reduced, and the electrons are eliminated. The phenomenon can be reduced.

FIG. 3B shows an example of a structure in which the phosphors H33 and H43 are higher than the grids G3 and G4 (closer to the filament). In this case, electrons emitted from the filament further emit fluorescent light. Concentrating on the bodies H33 and H43, the charge up of the insulating layer D can be further reduced. Since the insulating layer D of the present invention is a thin film, its thickness can be reduced to one tenth or less of a conventional thick film. Can be reduced.

The shapes of the grids and the openings of the insulating layer (the shape of the phosphor) in FIGS. 1, 2 and 3 have been described as squares, but may be any other shapes such as polygons and circles. . Note that the insulating layer D in FIGS. 1, 2 and 3 also has the function of a black matrix, so that there is no need to separately provide a black matrix. 1, 2 and 3 have back electrodes B1 to B9 which are not provided in the conventional fluorescent display tube.
Whether the heights of 1 to G7 are almost the same as the phosphors H11 to H7n,
Even in the case of lower than that, in order to supplement the operation of the grids G1 to G7, both can reliably control the electrons emitted from the filament to the anode electrode.

FIGS. 4 and 5 show an embodiment of the opening of the grid according to the present invention. 4 and 5, the insulating layer D in FIGS. 1, 2 and 3 is omitted, and only the grid G and the anode electrode A are shown. In the case of FIG. 4A, the opening of the grid G completely surrounds the phosphor H.
In the case of (b), one side of the rectangular opening is cut out to form a comb tooth shape. In the case of FIG. 5A, a notch is formed at one position of the opening of the grid G, and FIG.
In the case of (b), notches are formed at two places of the opening. In the case of FIGS. 4B, 5A, and 5B, the opening portion of the grid has a cutout portion, so that the bridge portion can be formed in the opening forming mask. Thus, the opening can be formed by mask evaporation as described later.

Here, a method of manufacturing the fluorescent display tube shown in FIGS. 1 to 5 will be described. First, a first glass substrate S
Metals such as ITO (compound of indium and tin) and Al (aluminum) are formed on the substrate 1 by sputtering, EB vapor deposition, or the like to form thin-film anode electrodes A1 to An and formed into a predetermined shape by chemical etching. Perform patterning. At this time, patterning can be performed simultaneously with the formation of the metal film using an evaporation mask. The anode electrodes A1 to An are formed to have a thickness of several tens nm to several thousand nm. This film thickness is selected in the above range in consideration of the resistivity of the metal material used, the wiring pattern, and the like. The material of the anode electrode may be any of metals such as ITO or Al when the fluorescent display tube is a direct-view type, that is, when the phosphor emits light from the second substrate S2 side, and may be a transmission type (FL type).
That is, when observing the light emission of the phosphor from the first substrate S1 side, ITO is used. On the anode electrodes A1 to An, SiOx (silicon oxide), SiN (silicon nitride) or the like is deposited by CVD (Chemical Vapor De).
The thin-film insulating layer D is formed by position, an opening is formed by chemical etching or RIE dry etching, and the anode electrode is exposed. The thickness of the insulating layer D is formed in the range of several hundred nm to several thousand nm.

On the insulating layer D, a metal such as ITO or Al is formed by sputtering or EB vapor deposition.
The thin film grids G1 to G7 are formed, and an opening is formed by dry etching or the like. The grid thickness is several tens
It is formed in the range of nm to several thousand nm. At this time, FIG.
The opening in (a) is formed by photolithography after forming the grids G1 to G7. In the case of FIG. 4B, FIG. 5A and FIG. 5B, since the opening has a notch,
A bridge can be provided in the opening forming mask.
Therefore, the openings in FIGS. 4B, 5A, and 5B can be formed by mask evaporation at the same time as the grids G1 to G7 are formed. FIG.
5 (a), 4 (b), 5 (a) and 5 (b), the phosphors H11 to H7n are formed by a slurry method on the portions of the anode electrode at the openings, and several thousand nm to 1000 nm.
It is formed with a thickness of 0 nm.

Next, thin film back electrodes B1 to B9 are formed on the second glass substrate S2 in the same manner as the formation of the anode electrodes A1 to An. Finally, the first substrate S1 and the second substrate S2 face each other, filaments F1 and F2 such as W (tungsten) are arranged between them, and both substrates and the side plate S3 are sealed with a sealing material. The fluorescent display tube is manufactured by performing a predetermined exhaust process.

Next, an embodiment of a method for driving a fluorescent display tube according to the present invention will be described. First, according to FIG.
The operation of B9 will be described. FIG. 6A shows the same cross-sectional view as FIG. 1B, and FIG. 6B shows an arrow Y in FIG.
FIG.

The back electrodes B1 to B9 are connected to the filament F
1. Control the emission and emission stop of electrons emitted from F2 to the anode electrodes A1 to An. That is, the back electrodes B1 to B
9, a control voltage consisting of a filament selection voltage and a filament non-selection voltage is applied to select the filament F1 or the filament F2, and emit electrons to the anode electrode. Here, for example, regarding the filament F1 and the anode electrode A3, the phosphors H23 and H33 close to the filament F1 and the phosphors H13 and H43 on both sides thereof.
Since the distance to the filament F1 is different between and, the amount of electrons emitted to the phosphor is different, and the emission luminance is different. Therefore, the present invention controls the control voltage applied to the back electrodes B1 to B9 so that electrons emitted from the linear filament are emitted substantially uniformly in a plane by providing a potential gradient. I have.

FIG. 6B shows the state of the control voltage applied to the back electrodes B1 to B9 and the potential gradient of the control voltage.

The back electrodes B1 to B9 have tens of volts to
A control voltage of about 10 V is applied to control electron emission and emission stop of the filament F1 or the filament F2. Here, the back electrodes B1 to B5 control the filament F1 in the group, and the back electrodes B5 to B9 control the filament F2 in the group.
Control. For example, if the filament F1 is an electron emission filament and the filament F2 is an electron emission stop filament, a positive control voltage is applied to the back electrodes B1 to B5 as a filament selection voltage, and the filament is applied to the back electrodes B6 to B9. A negative control voltage is applied as a non-selection voltage (the emission of electrons from the filament is stopped by covering the filament F2 with a negative potential). The filament selection voltage is set to a filament potential (0 V in this case) to +10 V, and the filament non-selection voltage is set to −10 V to less than the filament potential (0 V in this case).

FIG. 6B shows a potential gradient, for example,
0 V is applied to the back electrode B3 closest to the filament F1, 2 V is applied to the back electrodes B2 and B4 on both sides, and 4 V is applied to B1 and B5.
Is applied. By thus providing a potential gradient to the control voltage applied to the back electrode, electrons emitted from the filament can be uniformly and planarly diffused in a region including both sides of the filament. The technique of the back electrode in FIG. 6 can also be applied to a conventional fluorescent display tube.

Next, an embodiment of a method for directly selecting a filament according to the present invention will be described with reference to FIG. FIG.
(A) shows the same sectional view as FIG. 1 (b), and FIG. 7 (b)
FIG. 8 shows a plan view in the direction of arrow C in FIG.

In the example of FIG. 7, the filament that emits electrons is selected depending on whether the voltage applied to the filament is negative or positive. For example, when a negative voltage is applied to the filament F1 as a filament selection voltage, the filament F1 is selected, and a state where electrons can be emitted is obtained. On the other hand, a positive voltage is applied to the filament F2 to make it unselected,
The filament F2 is set to a state in which electron emission is stopped. FIG.
In the case of (b), the phosphors H11 to H4n located at the openings of the grids G1 to G4 become regions where electron irradiation is possible,
Phosphors H51 to H51 located at openings of grids G5 to G7
H7n is a region where electron irradiation is impossible. By using the control method using the control voltage and the potential gradient of the back electrode shown in FIG. 6 in combination with the direct selection method of the filament shown in FIG. 7, the filament can be reliably selected and the electrons emitted from the filament can be uniformly distributed on the surface. Can be diffused.

As described above, according to the present invention, a filament for emitting electrons to the anode electrode is selected by the filament selection voltage applied to the back electrode or the filament selection voltage applied to the filament, and at the same time, the filament selection applied to the back electrode is selected. By setting a potential gradient to the voltage, the electrons emitted to the anode are made uniform.

As a method of selecting the anode electrode and the grid, a selection method used in a conventional fluorescent display tube in which the anode electrode and the grid are arranged in a matrix can be used. For example, in the grids G1 to G7, time division
A voltage of 0 V to + several tens of volts (a voltage higher than the filament potential and lower than the anode potential (e.g., + several volts) on the selected grid, and a voltage lower than the filament potential (e.g., -several tens of volts) on the non-selected grids) are sequentially applied; By inputting a data signal of + several tens of volts to the anode electrodes A1 to An, a predetermined phosphor can be selected from the phosphors H11 to H7n to emit light.

FIG. 8 shows an embodiment of a filament selection circuit of the direct filament selection method of FIG. Circuits related to the anode electrode A, the grid G, and the back electrode B are schematically illustrated, and a data writing circuit, a grid scan circuit, a control voltage application circuit, and the like are omitted. The filaments F1 and F2 are provided with a secondary coil E of a transformer T.
An AC filament voltage is applied from f1 and Ef2.

The center taps Ek1 and Ek2 of the secondary coils Ef1 and Ef2 are connected to the power supply Eb via the resistors Rs and Rs.
And the switching elements Tr1, Tr
2 is grounded. The On / Off signal of the input terminal Ti is supplied directly to the switching element Tr1, and is supplied to the switching element Tr2 via a knot circuit. When the signal at the input terminal Ti is an On signal, the switching element Tr1 conducts and the secondary coil Ef
1 center tap Ek1 is grounded, and filament F1
Is applied with a ground potential. On the other hand, switching element Tr
2 is turned off because the On signal is inverted and the Off signal is supplied. Therefore, the center tap Ek
2 is connected to the power supply Eb, and the voltage of the same power supply is applied to the filament F2. When the signal of the input terminal Ti is Off
In the case of a signal, the conduction state of the switching elements Tr1 and Tr2 is opposite to the above, the ground potential is applied to the filament F2, and the voltage of the power supply Eb is applied to the filament F1. Thus, by continuously supplying the On / Off signal to the input terminal Ti, the filament F1 or the filament F2 can be selected in a time-division manner.

The circuit for switching or selecting the filament is not limited to the circuit shown in FIG. 8, but may be any circuit capable of alternately applying a positive voltage and a negative voltage to the filament F1 and the filament F2. FIG. 9 is a cross-sectional view of a model fluorescent display tube of an electric field analysis simulation performed to confirm the effect of the potential gradient of the control voltage in each embodiment of the present invention. The fluorescent display tube of the model has the same structure as the fluorescent display tube of FIG. S1 and S2 are a first substrate and a second substrate, A1 is an anode electrode, G1 to G7 are grids, B1 to B9 are back electrodes, F1 and F2 are filaments, and D is an insulating layer.

In the model, the first substrate S1 and the second substrate S
2, the distance between the back electrodes B1 to B9 and the filaments F1 and F2 is 0.15 mm, and the distance between the filaments F1 and F2 and the anode electrode A1 is:
0.7 mm, the interval between the filament F1 and the filament F2 is 2.0 mm, the voltage applied to the anode electrode A1 is 12.0V, and the voltage applied to the filaments F1 and F2 is 0V. The voltage applied to the grids G1 to G7 is +6 V for the selected grid and -6 V for the non-selected grid. FIG. 10 shows the results of a simulation of the model of FIG. FIG. 10A shows the result when a potential gradient is provided to the control voltage applied to the back electrode, and FIG.
0 (b) shows the result when no potential gradient is provided in the control voltage.

In FIG. 10, the horizontal axis represents the horizontal distance (Distance) of the first substrate S1 in FIG. 9, and 1.00 is -1.0 between the filament F1 and the filament F2.
0 corresponds to the left end of the anode electrode A1, and 3.00 corresponds to the right end of the anode electrode A1. The vertical axis represents the current density (Ip) of the anode electrode and the current density (Iback) of the back electrode.
And

FIG. 10A shows the results in two cases, that is, when the control voltage (Eback) applied to the back electrodes B1 to B9 is 0V, 2V, 4V and 0V, 3V, 6V. 0V is applied to the back electrodes B3 and B7, 2V and 3V are applied to the back electrodes B2, B4, B6 and B8, and 4V and 6V are applied to the back electrodes B1, B5 and B9. FIG. 10B shows the results in two cases where the control voltage (Eback) is 0V and 3V.

In the case of FIG. 10A, in each case,
The current density (Ip) becomes substantially uniform near and on both sides of the filament, and does not contribute to light emission.
back) hardly flows. That is,
It can be seen that the light emission luminance at each part of the anode electrode becomes uniform, and there is almost no reactive current.

In the case of FIG. 10B, the control voltage (Ebac
k) is 0 V, the current density (Iba
ck), but the current density (Ip) contributing to light emission hardly occurs in the intermediate portion between the filaments F1 and F2. That is, the filament F
The anode electrode in the intermediate portion between 1 and the filament F2 does not emit light. When the control voltage (Eback) is 3 V, the current density (Ip) becomes substantially uniform at all points of the anode electrode, but the reactive current increases near the filaments F1 and F2.

From these results, it can be seen that the potential gradient of the control voltage is effective in uniformly emitting electrons emitted from the filament to each portion of the anode electrode and making the current density in each portion uniform. Potential gradient voltage 0V, 2V, 4
V, 3 V, 6 V, and the like may be supplied using a power supply that generates these voltages, or may be supplied by a voltage dividing circuit using a resistor or the like. In the case of using a resistor, the resistance value of each electrode may be different depending on the shape and material of the back electrode. The distance between the filament and the anode electrode is
0.1 mm to several mm is preferable. Here, it is possible to increase the distance between the filament and the anode electrode by increasing the cutoff potential applied to the control electrode. However, considering the withstand voltage and cost of the driving IC, the The distance between the electrodes is more preferably about 0.5 mm to 1.5 mm.

[0038]

According to the fluorescent display tube of the present invention, since the back electrode is provided, even if the grid is arranged at a position lower than the phosphor, the back electrode complements the function of the grid.
Control of electrons emitted from the filament to the anode electrode can be reliably performed without any trouble. The fluorescent display tube of the present invention has a structure in which the anode electrode, the insulating layer, and the grid are formed of thin films, and the position of the opening of the grid is substantially the same as or lower than the phosphor. It is possible to reduce the up, and to eliminate the phenomenon of electron scuffing. Further, since the insulating layer of the present invention is a thin film, the thickness of the insulating layer can be reduced to one tenth or less of the conventional thick film. As a result, the charge-up of the insulating layer is also improved from this point. be able to.

The fluorescent display tube of the present invention comprises an anode electrode,
By forming the insulating layer and the grid with thin films, it has become possible to manufacture a high-definition fluorescent display tube. By setting the height of the grid and the phosphor as described above, it is possible to suppress the charge-up of the insulating layer of the conventional fluorescent display tube even in the case of a high definition structure. In the fluorescent display tube of the present invention, a mask can be vapor-deposited by forming a notch in the opening of the grid. As a result, since the openings can be formed by vapor deposition simultaneously with the formation of the grids, the manufacturing process is simplified, and grids having a small width can be arranged at a narrow pitch.

The fluorescent display tube of the present invention has a back electrode, and the back electrode is disposed on the opposite side of the anode electrode with the filament interposed therebetween. The release stop can be easily controlled, and by providing a potential gradient to the control voltage,
Electrons emitted from the filament to each part of the anode electrode can be uniformly diffused, and a planar electron source having a substantially uniform electron density can be realized.

The fluorescent display tube of the present invention switches between a filament for emitting electrons and a filament for stopping emission by a filament voltage applied to the filament.
Alternatively, the emission of electrons emitted from the filament can be performed and stopped more easily and reliably, and the uniformity of the emitted electrons can be achieved by adding the function of the back electrode. .

[Brief description of the drawings]

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

FIG. 2 shows a sectional view of a fluorescent display tube according to an embodiment of the present invention and an enlarged sectional view of a part of FIG.

FIG. 3 shows an enlarged sectional view of a part of FIG.

FIG. 4 shows an embodiment of an opening of a grid according to the present invention.

FIG. 5 shows another embodiment of the opening of the grid of the present invention.

FIG. 6 is a cross-sectional view and a plan view of a fluorescent display tube for describing a method of applying a control voltage according to the present invention.

7A and 7B are a cross-sectional view and a plan view of a fluorescent display tube for explaining a method of applying a filament selection voltage to a filament according to the present invention.

FIG. 8 shows an embodiment of a filament switching circuit of the fluorescent display tube of the present invention.

FIG. 9 shows the structure of an electric field analysis simulation model of the fluorescent display tube of the present invention.

FIG. 10 shows the results of an electric field analysis simulation of the fluorescent display tube of the present invention.

FIG. 11 shows a structure of a conventional fluorescent display tube.

[Description of Symbols] A, A1 to An Anode electrode B1 to B9 Back electrode D Insulating layer F1, F2 Filament G, G1 to G7 Grid H, H11 to H7n Phosphor S1 First substrate of glass S2 Second substrate of glass S3 Glass side plate

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Katsutoshi Kogo In-house 629 Futaba Electronics Co., Ltd., Oshiba, Mobara-shi, Chiba Prefecture Reference) 5C036 EE02 EE03 EE09 EF01 EF02 EF06 EG15 EG21 EG28 EG30 EG36 EG48 EH01 EH02 EH05 EH26 5C080 AA08 BB05 DD03 DD05 HH18 JJ02 JJ05 JJ06

Claims (10)

[Claims] A first substrate having a striped anode electrode and a striped grid formed in a matrix with an insulating layer interposed therebetween; and a second substrate having a striped back electrode formed therebetween. The filament is stretched in the longitudinal direction of the back electrode, an opening is formed in the grid and the insulating layer where the anode electrode and the grid intersect, and the phosphor is applied on the anode electrode in the opening. Characteristic fluorescent display tube. 2. The fluorescent display tube according to claim 1, wherein
A fluorescent display tube characterized in that the height of the grid is substantially the same as or lower than the phosphor. 3. The fluorescent display tube according to claim 1, wherein
A fluorescent display tube, wherein the grid is a thin film. 4. The fluorescent display tube according to claim 1, wherein
A fluorescent display tube, wherein a notch is formed in an opening of a grid. 5. The fluorescent display tube according to claim 1, wherein
A fluorescent display tube provided with means for setting a potential gradient to a filament selection voltage applied to a back electrode. 6. The fluorescent display tube according to claim 1, wherein
A method of driving a fluorescent display tube, characterized in that a filament selection voltage and a filament non-selection voltage are applied in a time division manner to each filament control group of a back electrode to select a filament from which electrons are emitted. 7. The fluorescent display tube according to claim 1, wherein
A method for driving a fluorescent display tube, characterized in that a filament selection voltage and a filament non-selection voltage are applied to a filament in a time division manner to select a filament from which electrons are emitted. 8. The fluorescent display tube according to claim 1, wherein
Filament selection voltage and filament non-selection voltage are applied in a time division manner to each filament control group of the back electrode, and filament selection voltage and filament non-selection voltage are applied to the filament in a time division manner to select a filament that emits electrons. A method for driving a fluorescent display tube, comprising: 9. The fluorescent display tube driving method according to claim 6, wherein a potential gradient is provided for a filament selection voltage applied to each filament control group of the back electrode. Drive method. 10. The fluorescent display tube according to claim 1, wherein a grid selection voltage is applied to the grid in a time-division manner, and a data signal is input to the anode electrode to select a phosphor to emit light. How to drive the display tube.