JP2003208862A - Fluorescent display tube and manufacturing method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fluorescent display tube and a manufacturing method thereof, capable of attaining a large opening rate, a simple manufacturing process, and little contamination of a fluorescent layer. <P>SOLUTION: A grid electrode 30 is provided by securing a sheet member 24 on which a thick conductive electrode 30 is formed along the periphery of an opening part 26 to a display surface 22 of a substrate 14, thus favorably restraining inconvenience in a case where a grid electrode 30 is provided on the top of a rib-shaped wall, which prolongs the process and increases material cost, and contamination of the fluorescent layer caused by lamination of a thick dielectric material after formation of the fluorescent layer or the like. The opening part 26 is formed so as to roughly surround a fluorescent layer 12, thus the lightening of the fluorescent layer 12 is never blocked by the grid electrode 30 as in the case that a grid electrode is provided on the top of the rib-shaped wall. Thus, this fluorescent display tube 10 can be obtained, which has a large opening rate, easy manufacturing process, and little contamination of the fluorescent layer 12. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an improvement in a fluorescent display tube and a method for manufacturing the same.

[0002]

2. Description of the Related Art Phosphor layers are fixed on a plurality of anodes provided on a display surface of a substrate, and thermoelectrons generated from a filament cathode erected above the anodes in a vacuum space are generated in the phosphor layers. Control electrode provided between the cathode and the cathode
2. Description of the Related Art There is known a fluorescent display tube of a type in which a phosphor layer is excited and emits light by being controlled by a (grid electrode) and selectively entering the phosphor layer. In such a fluorescent display tube, since a phosphor layer against which thermoelectrons generated from the cathode collide is provided in the vicinity of the cathode, the operating voltage is clearly displayed at a low level, and a plurality of types of emission colors different from each other are provided. There is a feature that color display can be performed by preparing the above-mentioned phosphor. Therefore, it is widely used as a display component such as an audio device and a display panel of an automobile or an aircraft.

[0003]

By the way, in one type of the above-mentioned fluorescent display tube, the grid electrode is composed of a conductor film fixed to the top of a rib-shaped wall projecting higher than it around the phosphor layer. There is a rib / grid structure. In such a structure, since the mesh-shaped grid electrode covering the phosphor layer is not used, uneven brightness and short circuit due to thermal deformation of the grid electrode when the display pattern of the phosphor layer is enlarged and the size is increased. It is possible to solve such a display defect as described above, and it is also possible to solve the problem that the decrease in the brightness of the fluorescent display tube due to the aperture ratio of the grid electrode is solved.

However, when forming the rib-shaped wall, it is necessary to repeat the steps of printing the thick film dielectric paste on the substrate and drying it in order to obtain the desired height dimension. Therefore, as compared with the case of using the mesh-shaped grid electrode, there is a problem that the process becomes longer and the material cost increases. Moreover, in such a manufacturing process, since the phosphor layer is formed in the initial stage during the formation of the rib-shaped wall, it is formed in the printing, drying, and firing steps for forming the rib-shaped wall. The phosphor layer is contaminated.
Therefore, there is also a problem that the brightness of the contaminated phosphor near the rib-shaped wall becomes low or hardly emits light. The contamination in the firing step is caused by, for example, a gas derived from an organic component contained in the thick film dielectric paste.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a fluorescent display tube having a large aperture ratio, a simple manufacturing process, and less contamination of a phosphor layer, and a manufacturing method thereof. To provide.

[0006]

In order to achieve such an object, the gist of the fluorescent display tube of the first invention is that it is fixed on a plurality of anodes provided on the display surface of the substrate. A plurality of phosphor layers, a filament cathode laid over the phosphor layers, and a plurality of control electrodes provided at a height position between the phosphor layers and the cathode, A fluorescent display tube of the type in which electrons generated from a filament cathode are controlled by the control electrode to selectively enter the phosphor layer to cause the phosphor layer to emit light. A plurality of openings at a plurality of locations above the phosphor layer of a size such that the entirety of each phosphor layer can be observed through the corresponding openings, and a thin plate-like thick film dielectric having a predetermined thickness dimension is provided. The body and the plurality of control electrodes A plurality of thick film conductor electrodes fixed to the surface of the thin plate-shaped thick film dielectric along the periphery of the plurality of openings, and a sheet member fixed to the display surface of the substrate. To include.

[0007]

A second aspect of the present invention for attaining the above-mentioned object is to provide a method for manufacturing a fluorescent display tube, which comprises the step of providing a plurality of anodes on the display surface of a substrate. And a step of fixing a plurality of phosphor layers on the plurality of anodes, a step of providing a plurality of control electrodes above the plurality of phosphor layers, and a filament cathode above the control electrodes. And a step of including a step of erection of the fluorescent display tube, in which electrons generated from the filament cathode are controlled by the control electrode to selectively enter the phosphor layer to cause the phosphor layer to emit light. (A) a plurality of phosphor layers having a size such that each of the plurality of phosphor layers is entirely observable through the corresponding openings. Be prepared at the position corresponding to And a plurality of thin plate-shaped thick film dielectrics fixed to the surface of the thin plate-shaped thick film dielectric along the peripheral edges of the plurality of openings to form the plurality of control electrodes. A sheet member fixing step of fixing a sheet member having a plurality of thick film conductor electrodes to the display surface of the substrate so that the plurality of openings are located above the plurality of phosphor layers. It is in.

[0008]

In this way, the control electrode is constituted by the thick film conductor electrode formed along the periphery of the opening of the sheet member fixed to the display surface of the substrate. Therefore, the control electrode is provided only by fixing the sheet member, in which the thick film conductor electrode is fixed to the surface of the thin plate thick film dielectric having the opening, to the display surface of the substrate. Inconvenience in providing the electrode on the top of the rib-shaped wall, that is, the process is long and the material cost is high, and the phosphor layer is contaminated due to the lamination of the thick film dielectric material after the phosphor layer is formed. It is preferably suppressed. Moreover, since the openings are formed so that each phosphor layer can be observed through the openings corresponding to the phosphor layers, the fluorescence is generated by the control electrodes as in the case where the control electrodes are provided on the top of the rib-shaped wall. The light emission of the body layer is not blocked. As described above, a fluorescent display tube having a large aperture ratio, a simple manufacturing process, and less contamination of the phosphor layer can be obtained.

The openings are provided, for example, at a plurality of locations above the plurality of phosphor layers in an inner peripheral edge shape along the outer periphery of each of the phosphor layers. Further, "the entire phosphor layer is observable" means that it is sufficient if almost the entire phosphor can be observed, and there is no hindrance to the display quality, or a part of the peripheral portion that is unnecessary for display is a part of the inner peripheral edge of the opening. It also includes the case where it is located outside.

[0010]

Other Embodiments Here, the sheet member is preferably fixed to the display surface of the substrate via a large number of spherical bodies having a predetermined maximum particle diameter. With this configuration, it becomes easy to fix the sheet member to the display surface while preventing the short circuit between the thick film conductor electrode and the phosphor layer and sufficiently reducing the mutual distance therebetween.

Further, preferably, the fluorescent display tube is provided with a thick film conductor wiring connected to the thick film conductor electrode on at least one of the inside of the sheet member and one surface thereof facing the display surface. is there. With this configuration, the wiring for connecting the thick film conductor electrode functioning as the control electrode to the external circuit is provided on the sheet member, which facilitates the formation of the wiring and the connection with the external circuit. Further, as compared with the case where both the wiring for the control electrode and the wiring for the anode are provided on the display surface of the substrate, there is an advantage that each wiring can be easily routed.

[0012] Preferably, the fluorescent display tube has, on the other surface of the sheet member facing the filamentary cathode, a portion similar to the filamentous cathode on a portion where the thick film conductor electrode is not provided. It is provided with a negative electrode made of a thick film conductor material that is set to an electric potential. By doing so, it is possible to suitably suppress the electrons generated from the filament cathode from entering the outside of the control electrode, that is, the portion other than the opening, on the sheet member, and thus it is possible to improve the luminous efficiency. There is.

Further, preferably, the fluorescent display tube is provided with an anode and a phosphor layer fixed on the anode on the other surface of the sheet member. By doing so, the phosphor layer on the sheet member as well as the phosphor layer provided on the display surface of the substrate can be made to emit light, so that the routing of the wiring does not become particularly complicated and the display diversity can be improved. Has the advantage of being increased.

Further, preferably, the fluorescent display tube has a through hole penetrating in a thickness direction at a position deviated from above the phosphor layer in the sheet member, and one end thereof is located on the substrate and The other end includes a pillar that is erected through the through hole so that the other end is located on the front plate disposed above the substrate to form a vacuum space. By doing so, such inconvenience occurs even when the fluorescent display tube having a large area of the display surface is formed to the extent that the front plate or the substrate is easily bent or the mechanical strength thereof is insufficient. Is suppressed by the above-mentioned pillar.

Further, preferably, a getter for maintaining a vacuum degree inside the fluorescent display tube is fixed to the surface of the sheet member. By doing so, there is an advantage that the getter can be provided at the same time as fixing the sheet member to the display surface of the substrate. The getter can be fixed by, for example, a glass frit.

Further, preferably, on the sheet member,
Another sheet member having the opening and the thick film conductor electrode functioning as the second control electrode is fixed in the same position as the opening while being insulated from each other. With this configuration, since the phosphor layer that emits light can be selected by the combination of the control electrode and the second control electrode, the number of wirings connected to the control electrode can be reduced. That is, driving by a so-called grid multi-matrix becomes possible.

Further, preferably, in the method for manufacturing a fluorescent display tube described above, (b) a film composed of a high-melting point particle layer in which particles having a melting point higher than a predetermined first temperature are bonded with a resin. A support preparing step of preparing a support having a forming surface,
(c) A dielectric paste film, in which constituent particles of a thick film dielectric material that can be sintered at the first temperature are combined with a resin, is formed on the film formation surface in a pattern corresponding to the thin plate-like thick film dielectric. Forming a dielectric paste film, and (d) the first
A conductor paste film forming step of forming a conductor paste film formed by bonding constituent particles of a thick film conductor material that is sintered at a temperature with a resin on the film forming surface in a pattern corresponding to the thick film conductor electrode, e) By heat-treating the support at the first temperature, the dielectric paste film and the conductor paste film are sintered without sintering the high melting point particle layer, and the thin plate-like thick film dielectric is obtained. The sheet member is manufactured by a process including a body and a firing process for producing the thick film conductor electrode.

In this way, the thick film dielectric is formed on the film forming surface composed of the high melting point particle layer having a melting point higher than the sintering temperature (first temperature) of the thick film dielectric material and the thick film conductor material. After the paste films of the material and the thick-film conductor material are respectively formed in a predetermined pattern, the thick-film dielectric material and the thick-film conductor material are subjected to heat treatment at a first temperature, whereby a thin plate shape is obtained. A sheet member having a thick film conductor electrode formed on the surface of the thick film dielectric is produced. Therefore, since the high melting point particle layer that is not sintered at the heat treatment temperature becomes a layer in which only the high melting point particles are arranged by burning the resin, the generated thick film is not fixed to the support. It can be easily peeled off from the film forming surface.
At this time, the paste film of the thick film dielectric material and the thick film conductor material can be formed on the film formation surface in a desired pattern using a simple facility by using an appropriate method according to the material and the application. It is possible. Moreover, it is easy to handle because it is applied to the film forming surface and is temporarily fixed until it is sintered by heat treatment. Therefore, the sheet member for providing the control electrode can be easily manufactured and used for manufacturing the fluorescent display tube.

The order of the conductor paste film forming step and the dielectric paste film forming step is appropriately determined according to the structure of the sheet member. That is, when the thick film conductor electrode is provided on both one surface and the other surface of the thin plate-shaped thick film dielectric, the conductor paste film forming step is performed before and after the dielectric paste film forming step, and the thick film conductor electrode is formed only on one side. When the conductor electrode is provided, the conductor paste film forming step is performed before or after the dielectric paste forming step. In addition, unlike the normal thick film formation, the thick film sintered on the layer in which only the high melting point particles are arranged as described above is not restricted by the forming surface at all when contracted. Therefore, warpage, deformation, and the like due to shrinkage resistance with the forming surface are suppressed, and in turn, cracks and the like caused by the warpage and deformation are also suppressed.

Further, preferably, the support preparing step is
The high melting point particle layer is formed on the surface of a predetermined substrate for manufacturing a sheet member. In this way, since the paste film is formed on the sheet member manufacturing substrate, the shape of the support is maintained even after the heat treatment, and thus the support is composed of only the high melting point particle layer. Compared with the case (for example, when the support is made of a ceramic green sheet), there is an advantage that the sheet member can be easily handled. Moreover, when such a support is used, the sheet member manufacturing substrate in which the high melting point particle layer is interposed between the substrate and the paste film does not restrain the paste film at the time of heat treatment, and Since the surface roughness of the paste film reflects only the surface roughness of the high melting point particle layer, the influence of the flatness, surface roughness, expansion coefficient, etc. of the sheet member manufacturing substrate on the quality of the sheet member is reduced. Therefore, high quality is not required for the sheet member manufacturing substrate.

Further, preferably, the sheet member manufacturing substrate does not deform at the firing temperature. By doing so, the shape of the film-formed surface is maintained at the initial shape even when the heat treatment for producing the thick-film dielectric and the thick-film conductor is performed, so that the high melting point particle layer is formed on the surface. By forming it, there is an advantage that it can be repeatedly used as a support. As the substrate for producing a sheet member, for example, general glass, heat-resistant glass, ceramic plate, metal plate or the like can be used as long as it satisfies the above conditions.

Further, preferably, in the step of forming the paste film, the conductor paste film and the dielectric paste film are respectively formed by using a thick film screen printing method. As a method of forming the paste film, for example,
Cost from various methods such as printing, sand blasting, lift-off, photo process using photosensitive paste,
It is possible to use an appropriate method selected according to the required accuracy, the balance with other steps, etc., but in the case of the printing method as described above, the film forming material is not used in the unnecessary portion of the film forming surface. Since it is not applied, there is an advantage that no material is wasted. That is, the waste of the material removed at the time of processing is extremely reduced as compared with that by pressing the ceramic green sheet, laser processing the ceramic sheet, or chemical etching of the metal material.

Preferably, the high melting point particles are made of an inorganic material such as ceramics or glass frit. As the high melting point particles, an appropriate inorganic material can be used as long as it does not soften after the resin forming the high melting point particle layer is burned. The specific material is appropriately selected according to the type of thick film material forming the sheet member and the firing temperature thereof.

[0024]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described in detail below with reference to the drawings.

FIG. 1 shows a fluorescent display tube 1 according to an embodiment of the present invention.
FIG. 3 is a perspective view showing the entire 0, with a part thereof cut away.
In the figure, a fluorescent display tube 10 includes a substrate 14 made of an insulating material such as glass, ceramics, enamel, etc., provided with a large number of phosphor layers 12 on one surface, and a glass spacer 16 formed in a rectangular frame shape. , A cover consisting of a transparent glass plate
A plurality of anode terminals 20 _P arranged respectively between the glass plate 18 and the substrate 14 and the spacer 16;
A grid terminal 20 _G and a cathode terminal 20 _K are provided, and the substrate 14, the spacer 16, and the cover glass plate 18 are bonded to each other by glass sealing to form an airtight container in the shape of a long flat box. A vacuum space surrounded by these members is formed therein.

The one surface 22 of the substrate 14 covered with the vacuum space functions as a display surface of the fluorescent display tube 10. The phosphor layer 12 provided on the display surface 22 is, for example, (Zn _x Cd _(1-x) ) S: Ag, Cl which emits red light, ZnS: Cu, Al which emits green light, and ZnS which emits blue light. : Cl, yellow emission (Zn
_x Cd _(1-x) ) S: Ag, Cl, etc., composed of phosphors of various emission colors, for example, 7-segment 8-shaped, rectangular,
Alternatively, it is formed in various shapes such as a circular shape.

A sheet member 24 is fixed to the display surface 22 so as to cover the plurality of phosphor layers 12. As shown in an enlarged view of a part of the display surface 22 in FIG. 2, the sheet member 24 is fixed to the thin plate-shaped thick film dielectric 28 having openings 26 at a plurality of locations and the peripheral edge of the opening 26. The thick film conductor electrode 30 is provided.
The thin plate-like thick film dielectric is, for example, PbO-B ₂ O ₃ -SiO ₂ -Al ₂ O.
₃ -ZnO-TiO ₂ system or a combination of these, low softening point glass and thick film dielectric material such as ceramic filler such as alumina, 20-30
It has a thickness of about (μm). The thick film conductor electrode 30 is a thick film conductor containing, for example, silver (Ag), nickel (Ni), aluminum (Al), copper (Cu), carbon (C) as a conductor component, and for example, 5 The thickness of the thin plate-shaped thick film dielectric 28 is about 20 to 20 μm, and the width of the upper surface 32 of the thin plate-shaped thick film dielectric 28 is about 50 to 500 μm.

As is clear from FIG. 3 showing the main part of the cross-sectional structure of the fluorescent display tube 10, the opening 26 is provided above (just above) each of the plurality of phosphor layers 12. The shape of the opening is slightly smaller than that of the outer peripheral edge of the phosphor layer 12 located below. That is, the phosphor layer 12 is formed in an area slightly larger than the opening area of the opening 26, and almost the entire area can be observed through the opening 26, but the peripheral portion of the phosphor layer 12 is hidden.

Further, since the thick film conductor electrode 30 is located at the peripheral portion of the opening 26 having the above-mentioned shape, the thick film conductor electrode 30 substantially surrounds the phosphor layer 12 above it. It is provided and functions as a grid electrode (control electrode) for controlling light emission of the phosphor layer 12 as described later. The thick film conductor electrode 30 is provided in a range extending from the upper surface 32 to the inner peripheral surface of the opening 26, as shown in FIG.

In FIG. 2, reference numeral 34 designates a pillar standing on the substrate 14 for supporting the cover glass plate 18. The sheet member 24 is provided with a column through hole 36 through which the column 34 penetrates at an appropriate position, and although the sheet member 24 covers substantially the entire surface of the display surface 22, the display surface is not displayed. Even at the position on the inner peripheral side of 22, the bending deformation of the cover / glass plate 18 can be suppressed. The surface of the support column 34 is made of, for example, ITO.
(Indium tin oxide), ATO (antimony tin oxide), and a conductor film formed of an organic metal material such as silver (Ag) or gold (Au). In addition, the through hole 36 for the support
A conductor film 38 electrically insulated from the thick film conductor electrode 30 is provided at a position such as the periphery of the. Although only a part of the conductor film 30 is shown in the drawing, the conductor film 30 is actually provided on substantially the entire upper surface 32 of the sheet member 24 excluding the periphery of the opening 26.

Further, in FIG. 3, a large number of spherical spacers 40 are interposed between the substrate 14 and the sheet member 24. The spherical spacer 40 has, for example, a maximum diameter of about 150 to 300 (μm), preferably 200 to 250 (μm).
It is composed of glass beads, ceramic balls, or the like having a substantially uniform diameter adjusted to some extent, and is bonded to the substrate 14 and the sheet member 24 by a glass frit (not shown) or the like. That is, in the present embodiment, the sheet member 24 is disposed on the display surface 2 of the substrate 14 via the spherical spacer 40.
It is fixed to 2. The height position of the sheet member 24, that is, the gap between the phosphor layer 12 and the thick film conductor electrode 30 is substantially determined by the maximum diameter of the spherical spacer 40 interposed between the substrate 14 and the sheet member 24. . for that reason,
Since the mutual distance between the thick film conductor electrode 30 functioning as a grid electrode and the phosphor layer 12 is a constant value,
The grid electrode 30 and the phosphor layer 12 are prevented from being short-circuited, and the distance therebetween is as small as described above. Further, the spherical spacer 40 as described above suppresses the maximum diameter by removing, for example, the coarse particle side of the group having an appropriate particle size distribution with a filter (mesh or the like) having an opening defined according to the maximum diameter. The ratio of the maximum diameter can be increased.

Returning to FIG. 1, a pair of filament supporting frames 42 (only one positioned on the right side in the figure) having the cathode terminals 20 _K are fixedly provided on both ends of the substrate 14, respectively. A plurality of fine filament filaments (filament cathodes) 44 functioning as a directly heated cathode (cathode) are parallel to the longitudinal direction of the substrate 14 and are separated from the display surface 22 between the filament support frames 42. It is stretched so as to be at a predetermined height position. The sheet member 24 provided with the grid electrode 30 is arranged at a height position between the filament 44 and the phosphor layer 12. In the fluorescent display tube 10,
Although an exhaust hole for exhausting and sealing the inside of the vacuum container and a getter for maintaining the internal vacuum degree after sealing are provided, these are omitted in the drawing. The getter is attached to, for example, the filament support frame 42 described above, but in this embodiment, the upper surface 3 of the sheet member 24 is used.
It may be provided in a part of 2 so as not to interfere with the grid electrode 30 and the conductor film 38.

Further, as shown in FIGS. 2 and 3, the display surface 22 has a plurality of substantially the same shape as the phosphor layer 12 or a slightly larger area than the phosphor layer 12. An anode 46 is provided below the phosphor layer 12. The anode 46 is made of, for example, a graphite layer having a thickness of about 20 to 40 (μm), and is connected to the anode connection wiring 48, respectively. The wiring 48 is formed by printing thick film conductor paste to a thickness of about 15 (μm) by a screen printing method or the like and baking it, or by vapor deposition and etching treatment of an aluminum thin film or the like. The anode 46 is provided so as to partially overlap the end of the wiring 48. Wire 48 is the anode terminal 20 _P is the substrate edge that is provided routed to (see FIG. 1), where it is connected to each unit defined by the driving method in the anode terminal 20 _P. Although the wiring 48 is exposed in the drawing, it may be covered with a thick film insulating layer.

On the other hand, the thick film conductor electrode, that is, the grid electrode 30 provided on the sheet member 24 is also connected to the grid terminal 20 _G for each drive unit. This connection structure is required in FIG. The lower surface 50 of the sheet member 24 is used as shown in FIG. The lower surface 50 is made of a thick film conductor like the grid electrode 30,
Grid wiring 52 with a thickness of about 20 (μm)
Is provided. The thickness of the grid wiring 52 is
For example, when a thick film conductor paste containing fine powder silver (Ag) as a conductor component is used, the thickness becomes as thin as several μm or less, and when a thick film conductor paste containing aluminum (Al) powder as a conductor component is used. It becomes thicker than tens of μm. The grid wiring 52 is formed so that its end is located on the opening edge of the opening 26, and the opening edge is formed on the grid electrode 30 provided in the range extending over the inner peripheral surface of the opening 26. Connected by. As described above, the sheet member 24 is positioned apart from the display surface 22 by being fixed to the substrate 14 via the spherical spacer 40, but the sheet member 24 has a manufacturing process described below. Since it is a sheet-like thick film manufactured through the process and has sufficient flexibility,
If a portion of the peripheral portion that is not supported by the spherical spacer 40 is provided, it will contact the display surface 22 there. For this reason, for example, the contacting portion is connected to the grid terminal 20
_If it is on the _G or on the wiring on the display surface 22 connected to it, it can be easily connected to the grid terminal 20 _G.

When the fluorescent display tube 10 constructed as described above is driven, a predetermined heating current is constantly applied to the plurality of filaments 44, for example, to the zero (V) filaments 44. On the other hand, a relatively positive acceleration voltage of, for example, about 20 (V) is applied to the plurality of grid electrodes 30 in a predetermined order and scanning is performed. Then, in synchronization with the timing of the scan, a drive voltage of about 20 (V), which is the same as the above acceleration voltage, which is positive with respect to the cathode potential, is applied to a predetermined anode wiring 48 corresponding to the input data. As a result, the thermoelectrons emitted from the filament 44 are accelerated by the grid electrode 30 to which a positive voltage is applied,
When a positive voltage is also applied to the phosphor layer 12 located inside (that is, substantially surrounded) via the anode 46, electrons are incident on the phosphor layer 12 to excite it to emit light. . However, even if a positive voltage is applied to the phosphor layer 12, if a negative cutoff bias of about several (V) is applied to the filament 44 on the grid electrode 30 located thereabove, heat will be generated. The electrons do not reach the phosphor layer 12 and the phosphor layer 12 does not emit light. Therefore, in a state in which the thermoelectrons are emitted by the current flowing through the filament 44, the desired one of the phosphor layers 12 is selected in synchronization with the timing when the acceleration voltage is sequentially applied to the grid electrode 30. Also, when a positive voltage is applied, so-called dynamic driving causes light emission display in a desired pattern.

In this case, according to the present embodiment, the phosphor layer 12 having the opening 26 located thereunder (that is, corresponding to the opening 26) is provided in such a size that the entire phosphor layer 12 can be observed through the opening 26. Therefore, the grid electrode 30 does not block the light emission of the phosphor layer 12. Therefore, compared with the case where a mesh-shaped grid electrode is used, the luminous efficiency is improved.

When driven in this way, the conductor film 38 is kept at the same potential as the filament 44. Therefore, the thermoelectrons generated from the filament 44 are
Even if it goes to a portion of the sheet member 24 where the opening 26 is not provided, the thermoelectrons are cut off.
Like the thermoelectrons directed to the grid electrode 30 to which the bias is applied, the course thereof is blocked by the negative electric field formed by the conductor film 38. Therefore, the probability that the generated thermoelectrons enter the phosphor layer 12 through the opening 26 is increased, and high luminous efficiency is obtained. In addition, the pillar 34
The conductor is also covered with a conductor such as ITO. However, the conductor is charged with the thermoelectrons incident on the surface of the pillar 34 exclusively, and a negative electric field that impedes the course of the thermoelectrons directed to the phosphor layer 12 is generated. It is for preventing formation.

The fluorescent display tube 10 is manufactured, for example, according to the process shown in FIG. That is, first, in the wiring forming step 54, the anode wiring 48 is formed on the substrate 14 by using, for example, the thick film screen printing method or the vapor deposition method, and then in the anode forming step 56, for example, the thick film screen printing method or the like is performed. The graphite paste is applied from above to form the anode 46. Next, in a phosphor layer forming step 58, the phosphor layer 12 is formed by applying a phosphor paste on the anode 46 by using, for example, a thick film screen printing method.

Subsequently, in a sheet member fixing step 60, glass paste or the like containing the spherical spacer 40 is applied to a portion of the substrate 14 where the anode wiring 48, the phosphor layer 12 and the like are not formed. The separately manufactured sheet member 24 is placed on the sheet member 24 and heat-treated to fix it. Then, for example, a lead frame manufactured separately,
The spacer 16 and the cover glass plate 18 are sequentially placed, and heat treatment is performed in the sealing step 62. The lead frame is one in which the terminal 20 and the filament supporting frame 42 are integrated. As a result, the lead frame is fixed to the substrate 14 by the glass frit or the like previously applied on the substrate 14, and at the same time, the spacer 16
The cover glass plate 18 is fixed to the substrate 14 via
An airtight space is formed between them. Then, in the evacuation / sealing step 64, the fluorescent display tube 10 is obtained by exhausting from the exhaust hole (not shown) to evacuate the inside and then sealing the exhaust hole.

In the above manufacturing process, the sheet member 24
Is performed in accordance with, for example, the process shown in FIG. 6 to which the well-known thick film printing technique is applied. Hereinafter, a method of manufacturing the sheet member 24 will be described with reference to FIGS. 7A to 7F showing the states at the essential stages of the manufacturing process.

First, in the substrate preparing step 66, a substrate 68 (see FIG. 7) for thick film printing is prepared, and its surface 70 and the like are subjected to appropriate cleaning treatment. This substrate 68 is one which is hardly deformed or deteriorated during the heat treatment described later, and has a thermal expansion coefficient of about 87 × 10 ⁻⁷ (/ ° C.) and a softening point of about 740 (° C.), for example. A glass substrate made of soda lime glass or the like having a strain point of about 510 (° C.) is preferably used. The thickness of the substrate 68 is, for example, about 2.8 (mm), and the size of its surface 70 is made sufficiently larger than that of the sheet member 24. In this embodiment, the substrate 68 corresponds to a sheet member manufacturing substrate.

Next, in the peeling layer forming step 72, the peeling layer 74 to which the high melting point particles are bonded by the resin is provided on the surface 70 of the substrate 68 with a thickness of, for example, about 5 to 50 (μm).
The high melting point particles, for example, an average particle size of 0.5 ~ 3 (μm) high softening point glass frit and an average particle size of 0.01 ~ 5
It is a mixture of ceramic filler such as alumina and zirconia (about μm). The high softening point glass is, for example, one having a softening point of about 550 (° C.) or higher, and the softening point of the high melting point particles as a mixture is, for example, 550.
(° C) or higher. Further, the resin is, for example, 350
It is an ethyl cellulose resin that is burned down at about (° C.). The peeling layer 74 is made of, for example, an inorganic material paste 76 in which the high melting point particles and the resin are dispersed in an organic solvent such as butyl carbitol acetate (BCA).
For example, as shown in FIG. 7 (a), it is provided by coating on substantially the entire surface of the substrate 68 using a screen printing method and drying at room temperature, but it can also be provided by coating with a coater or a film laminate. FIG. 7B shows a stage in which the release layer 74 is formed in this way. In addition,
In FIG. 7A, 78 is a screen and 80 is a squeegee. In this embodiment, the substrate 68 provided with the release layer 74 corresponds to the support, and the surface of the release layer 74 corresponds to the film forming surface, and the substrate preparing step 66 and the release layer forming step 72 support the substrate. Corresponds to the body preparation process.

In the subsequent thick-film paste layer forming step 82, a thick-film dielectric paste 84 and a thick-film conductor paste 86 (see the figure) for forming the thin plate-shaped thick-film dielectric 28, the grid electrode 30, and the grid wiring 52, respectively. (See 7 (a))
Are sequentially applied and dried in a predetermined pattern on the peeling layer 74 by using a screen printing method or the like similarly to the inorganic material paste 76. As a result, the conductor printed layer 88 for forming the portion of the grid electrode 30 located on the upper surface 32 of the thin plate-shaped thick film dielectric 28, the dielectric printed layer 90 for forming the thin plate-shaped thick film dielectric 28, A conductor printed layer 92 for forming the grid wiring 52 and a conductor printed layer 94 for forming a portion of the grid electrode 30 located on the inner wall surface of the opening 26 are sequentially formed. The thick film conductor paste 86 is, for example, a conductor material powder such as silver powder,
A glass frit and a resin are dispersed in an organic solvent. The thick film dielectric paste 84 is, for example, dielectric material powder such as alumina or zirconia, glass frit, and resin dispersed in an organic solvent. The above glass frit is, for example, Pb.
OB ₂ O ₃ —SiO ₂ —Al ₂ O ₃ —TiO ₂ -based low softening point glass or the like is used, and the same resin and solvent as the inorganic material paste 76, for example, are used.

At this time, when the dielectric print layer 90 and the conductor print layers 88 and 92 are formed, the screen 78 is
The thin plate-like thick film dielectric 2 shown in FIG. 2 and FIG.
8, the portion of the grid electrode 30 located on the upper surface 32,
And those having opening patterns corresponding to the shapes of the grid wirings 52 are used, and the thick-film dielectric paste 84 and the thick-film dielectric paste 84 having predetermined thickness dimensions are set so that the above-mentioned film thicknesses are obtained after firing shrinkage. Thick film conductor paste 86 is applied. As a result, a thick film (printed film) having a shape as shown in FIGS. 7C to 7E is formed. Note that, in the drawing, for convenience of illustration and description, a gap is formed between the dielectric printing layer 90 and the peeling layer 74, but
Since the applied thick film dielectric paste 84 has sufficiently high fluidity and the applied thickness is sufficiently thin, the lower surface follows the applied surface, that is, the surface of the release layer 74, and the upper surface is flat.

On the other hand, when forming the conductor print layer 94,
For example, by using a screen 78 having an opening slightly protruding inward from the inner wall surface of the opening 26 provided in the thin plate-shaped thick film dielectric 28, the thick film conductor paste 86 is used as the dielectric printing layer 90. Is applied so as to flow down along the inner wall surface of the opening 26 from the upper surface. At this time, as the thick-film conductor paste 86, for example, fine particles having high fluidity such as silver particles which are conductor components are used.
As a result, a print film having a shape as shown in FIG. 7F, that is, a print film along the inner wall surface of the opening 26 is formed.
Since the conductor print layers 88 and 92 have a thickness of about 5 to 10 (μm), they are formed by printing once, but the dielectric print layer 90 has a thickness of about 30 (μm). Therefore, printing and drying are repeated about three times to form a laminated layer until an appropriate thickness dimension is obtained. Note that, in FIG. 7 described above, the thick film printing layers 88 to 94 are drawn relatively thick for convenience of illustration.

After forming the thick film printing layers 88 to 94 as described above and drying to remove the solvent, in the baking step 96, the substrate 68 is placed in a furnace chamber of a baking device (not shown), and the thick film dielectric layer is formed. Body paste 84 and thick film conductor paste 8
The heat treatment is performed at a firing temperature of, for example, about 550 (° C.) corresponding to the six types.

In the above heat treatment process, the thick film printing layers 88 to 94 have a sintering temperature of, for example, about 550 (° C.), so that the resin component thereof is burned off, and the dielectric material, the conductor material, and The glass frit is sintered,
The thin plate-shaped thick film dielectric 28, the grid electrode 30, and the grid wiring 52, that is, the sheet member 24 are generated.
FIG. 7 (g) shows this state. At this time, as described above, the release layer 74 has 550 of the inorganic component particles.
Since the resin component has a softening point of (° C.) or higher, the resin component is burnt out, but the high melting point particles (glass powder and ceramic filler) are not sintered. Therefore, when the resin component is burnt out as the heat treatment progresses,
As shown in FIG. 5, the peeling layer 74 becomes the particle layer 100 composed only of the high melting point particles 98.

FIG. 8 is a diagram schematically showing a part of the right end in FIG. 7 (g) in an enlarged manner to show the progress of sintering in the above heat treatment. The particle layer 100 generated by burning off the resin component of the peeling layer 74 is a layer in which the high melting point particles 98 are simply stacked, and the high melting point particles 98 are not bound to each other. Therefore, the thick film printed layers 88 to
When 4 contracts, its high melting point particles 98 act like rollers. As a result, even on the lower surface side of the thick film printing layers 88 to 94, a force that prevents the contraction between the thick film printing layers 88 to 94 and the substrate 68 does not act, so that the thick film printing layers 88 to 94 are contracted similarly to the upper surface side. No warping or the like has occurred.

In this embodiment, the thick film printing layer 8 is used.
When the sintering of Nos. 8 to 94 starts, the substrate 68 does not prevent the firing shrinkage thereof due to the action of the particle layer 100 as described above. Therefore, the thermal expansion of the substrate 68 does not substantially affect the quality of the thick film produced. When the substrate 68 is repeatedly used or the heat treatment temperature becomes high, heat resistant glass having a higher strain point (for example, a thermal expansion coefficient of about 32 × 10 ⁻⁷ (/ ° C.) and a softening point of 820 ( Borosilicate glass with a thermal expansion coefficient of 5 × 10 ^-7 (/ ° C) and a softening point of 15
Quartz glass (about 80 (° C.)) can be used. Also in this case, the thermal expansion amount of the substrate 68 is extremely small in the temperature range where the binding force of the dielectric material powder or the like is small, and therefore the thermal expansion does not affect the quality of the thick film produced.

Returning to FIG. 6, in the peeling step 102, the generated thick film, that is, the sheet member 24 is peeled from the substrate 68. Since the high melting point particles 98 are simply piled up in the particle layer 100 interposed between them, the peeling process can be easily performed without using any chemicals or devices. At this time, the high melting point particles 98 can be attached to the back surface of the sheet member 24 with a thickness of about one layer, but the attached particles are removed by using an adhesive tape, an air blow, or the like as necessary. The substrate 68 from which the thick film is peeled off is not likely to be deformed or deteriorated at the firing temperature as described above, and thus is repeatedly used for the same purpose.

In the sheet member fixing step 60 shown in FIG. 5, the sheet member 24 manufactured as above is manufactured.
However, it is placed on the substrate 14 in such a direction that the surface on the conductor printed layer 88 side is the upper side. Therefore, the sheet member 2
In No. 4, the peeling surface located on the peeling layer 74 side is made to face the filament 44. Since the peeling surface is formed through the manufacturing process as described above, it is substantially flat, so that the grid electrode 30 and the filament 4 are separated.
The distance between the fluorescent display tube 4 and the display surface 4 is substantially uniform over the entire surface of the fluorescent display tube 10.

As described above, according to this embodiment, the grid electrode 30 is formed by fixing the sheet member 24 having the thick film conductor electrode 30 formed along the periphery of the opening 26 to the display surface 22 of the substrate 14. Is provided. Therefore, inconvenience in providing the grid electrode 30 on the top of the rib-shaped wall, that is, the process becomes long and the material cost increases, and the phosphor layer is formed due to the lamination of the thick film dielectric material after the phosphor layer is formed. And the like are suitably suppressed. Moreover, since the opening 26 is formed to substantially surround the phosphor layer 12, the grid electrode 30 blocks the light emission of the phosphor layer 12 as in the case where the grid electrode is provided on the top of the rib-shaped wall. Never be. As described above, the fluorescent display tube 10 having a large aperture ratio, a simple manufacturing process, and less contamination of the phosphor layer 12 can be obtained.

Further, according to the present embodiment, since the grid wiring 52 is provided on the lower surface of the sheet member 24 as described above, the grid wiring 52 is spatially separated from the anode connection wiring 48, so that three-dimensionally. Since it is possible to form wirings that intersect, wirings can be easily routed.

Further, according to the present embodiment, as described above, after the thick film printing layers 88 to 94 are formed on the peeling layer 74, heat treatment is performed at a predetermined temperature so that the thin plate-shaped thickness is increased. The sheet member 24 having the grid electrode 30 formed on the surface of the film dielectric 28 is manufactured. Therefore, in the peeling layer 74 that is not sintered at the heat treatment temperature, the resin layer is burned off, so that only the high melting point particles 98 are lined up.
Since it is 0, the generated thick film is not fixed to the film forming surface and can be easily peeled from the film forming surface.

Next, another embodiment of the present invention will be described. In the following embodiments, the same parts as those in the above-mentioned embodiments are designated by the same reference numerals and the description thereof will be omitted.

In the embodiment shown in FIG. 9, the seat member 24 is provided on the seat member 24a via the spherical spacer 40.
b is overlaid. The sheet member 24a is the same as that shown in FIG.
The sheet member 24 is substantially the same in structure as the sheet member 24 shown in FIG. 3, and a predetermined one of the grid electrodes 30 is connected to the common grid terminal 20 _G. On the other hand, the seat member 24b is also substantially the same as the above-mentioned seat member 24, that is, substantially the same as the seat member 24a.
A predetermined one of the plurality of grid electrodes 30 is connected to a common grid terminal 20 _G so that the combination is different from that of the sheet member 24 a and the sheets on the sheet member 24 a are electrically insulated from each other. Has been done. The positions of the openings 26, 26 of the sheet members 24a, 24b are the same position when viewed from the observation direction.

In the thus constructed fluorescent display tube, when the accelerating voltage is applied to both the grid electrode 30 on the sheet member 24a and the grid electrode 30 on the sheet member 24b, it is generated from the filament 44. The thermoelectrons will be directed to the phosphor layer 12 surrounded by them. Therefore, the two sheet members 24a and 24b
The wiring of the grid wiring 52 in each of the cases is simplified, the pattern formation is facilitated, and the matrix drive pattern in which the number of necessary drivers can be reduced is also facilitated.

In the embodiment shown in FIG. 10, a sheet member 104 is provided instead of the sheet member 24. The sheet member 104 includes a plurality of thick film conductor electrodes that function as the second grid electrodes 106 on the lower surface 50 of the thin plate-shaped thick film dielectric 28. The plurality of grid electrodes 30 of the sheet member 104 are connected to a common grid terminal 20 _G , and the plurality of grid electrodes 106 are in a combination different from that of the grid electrode 30. Certain objects are connected to the common grid terminal 20 _G. In addition, the grid electrode 30 has an upper surface 32.
The grid electrode 106 is provided in a range from to the middle of the inner wall surface of the opening 26.
Since it is provided so as to project to the inner peripheral side of 6, the gap is formed in the opening 26 between them, and the grid electrode 30 and the grid electrode 106 are electrically insulated from each other. Has been. Therefore, also in the present embodiment, as in the case shown in FIG. 9 described above, the phosphor layer 12 that emits light by the combination of the two grid electrodes 30 and 106.
Can be selected. Therefore, this embodiment also has an advantage that the grid wiring 52 on each of the upper surface 32 and the lower surface 50 can be formed in a simple shape.

The sheet member 104 as described above is
For example, it is manufactured by the method as shown in FIG. That is, after the conductor printed layer 108 for forming the grid electrode 106 and the grid wiring 52 is formed in an annular shape on the peeling layer 74, the second peeling layer 110 is formed on the inner circumferential side of the conductor printed layer 108. To cover a part of. Second
The peeling layer 110 is formed of, for example, the same inorganic material paste 76 as the peeling layer 74. FIG. 11A shows this state. Then, a dielectric printing layer 90 for forming the thin plate-shaped thick film dielectric 28 is formed thereon. At this time,
The inner peripheral edge of the dielectric printed layer 90 is in contact with the second peeling layer 110 as shown in FIG. 11B, and the conductor printed layer 108 is completely covered. Then, a conductor printed layer 88 (94) for forming the grid electrode 30 from above
To form. When forming the conductor printed layers 88 and 94,
Although the thick-film conductor paste 86 flows down along the inner wall surface of the opening 26, it cannot reach the conductor printed layer 108.

After the thick film screen printing is performed in this manner, the thick film printing layers 108, 90, 8 are subjected to a baking treatment.
Conductors and dielectrics are generated from the second release layer 110.
Is neither sintered nor burnt out. for that reason,
Since the printed conductor layers 108 and 94 are sintered without being in contact with each other, their electrical insulation is ensured. The second release layer 110 made of the inorganic material paste 76 is removed at the same time when the sheet member 104 is released from the release layer 74.

In the present embodiment, the grid wiring 52 connected to the grid electrode 30 has, for example, the upper surface 3
2 will be provided.

In each of the above-described structural examples, only the grid electrode 30 and its wiring are provided on the sheet member 24 and the like. For example, as shown by the dashed line in FIG. 112 and the phosphor layer 114 may be provided. These anode 112 and phosphor layer 114
After the completion of the manufacturing process of the sheet member 24, that is, after the peeling process 102, it may be formed by using a thick film screen printing method or the like, as in the case of forming the display surface 22 of the substrate 14. When the baking step 96 of the sheet member 24 does not particularly affect the function of the phosphor layer 114, it may be provided in the thick film paste layer forming step 82. The anode 112 is, for example, a thin plate-shaped thick film dielectric 28.
It is possible to provide an independent dedicated wiring on the upper surface 32 of the above, or to connect to the grid wiring 52 common to the specific grid electrode 30 and connect to the terminal 20 similarly to the grid electrode 30.

With the above structure, the sheet member 24
Since the phosphor layer 114 is also provided on the substrate 14,
Compared with the case where all the phosphor layers 12 are provided above, it is possible to increase the variety of display while suppressing the wiring from being complicated. The phosphor layer 114 described above is used.
The time when the light is emitted depends on the connection configuration of the wiring, but for example, if it is connected to the wiring common to the grid electrode 30, it is emitted together with the grid electrode 30, and if it is connected to an independent wiring, a voltage is applied to the wiring. As long as the voltage is applied, the light is emitted regardless of the voltage applied to the grid electrode 30.

Although one embodiment of the present invention has been described in detail with reference to the drawings, the present invention can be implemented in still another mode.

For example, in the fluorescent display tube 10 of the embodiment, the phosphor layers 12 are provided in various character patterns, but in the fluorescent display tube in which the dot pattern and the character pattern are provided side by side. The invention applies as well. In such a fluorescent display tube, a mesh grid electrode or a rib grid electrode may be provided in the dot pattern portion as in the conventional case. However, the present invention may be applied to the dot pattern portion as long as the dot spacing is sufficiently large and the support of the sheet member 24 such as the spherical spacer 40 can be arranged.

Further, in the embodiment, the anode connection wiring 48 is provided in an exposed state.
It may be covered with an insulating layer having an opening at the position.

The support column 34 is formed by the cover glass plate 18
The column 34 is not necessary for a fluorescent display tube that is so small that there is no possibility of such a problem, because the column 34 is provided when it is predicted that the bending deformation will occur.

In the embodiment, the grid wiring 52 is provided on the sheet member 24.
It may be provided on the upper side so that the sheet member 24 is fixed by a conductive adhesive or the like, and at the same time, connected to the grid remote line on the substrate 14.

Further, the conductor film 38 for improving the luminous efficiency
Need not necessarily be provided.

Further, in the embodiment, the opening 26 is formed in a shape substantially similar to that of the phosphor layer 12, but even if the opening 26 is formed to have a larger opening and a different opening shape than the phosphor layer 12, the entire opening 26 is formed. There is no problem if the light can be emitted with sufficient uniformity. On the contrary, as the opening having a shape smaller than the phosphor layer 12, only a part of the opening may be observed.

Further, in the embodiment, the sheet member 24
Was fixed to the substrate 14 via the spherical spacer 40, but if it can prevent a short circuit with the conductor on the substrate 14, it may be fixed directly.

In the embodiment, the grid electrode 3
Although 0 is provided on the upper surface 32 of the sheet member 24 and the inner peripheral surface of the opening 26, either one may be used.

Although not illustrated one by one, the present invention can be variously modified without departing from the spirit of the invention.

[Brief description of drawings]

FIG. 1 is a perspective view with a part cut away for explaining a structure of a fluorescent display tube according to an embodiment of the present invention.

FIG. 2 is a diagram for explaining the configuration of a part of the display surface of the substrate of the fluorescent display tube of FIG. 1 in an enlarged manner.

3 is a cross-sectional view illustrating a main part of the fluorescent display tube of FIG.

FIG. 4 is a diagram illustrating a back surface of a sheet member included in the fluorescent display tube of FIG.

5A to 5C are process diagrams illustrating a manufacturing process of the fluorescent display tube of FIG.

6A to 6C are process diagrams illustrating a method of manufacturing a sheet member in the manufacturing process of FIG.

7 (a) to 7 (f) are cross-sectional views for explaining main steps of the manufacturing process of FIG.

FIG. 8 is a diagram for explaining the function of the peeling layer by enlarging the right end portion of FIG. 7 (f).

FIG. 9 is a sectional view corresponding to FIG. 3 for explaining a main part of a fluorescent display tube according to another embodiment of the present invention.

FIG. 10 is a sectional view corresponding to FIG. 3 for explaining a main part of a fluorescent display tube according to still another embodiment of the present invention.

FIG. 11 is a diagram illustrating a method for manufacturing the sheet member used in the example of FIG.

[Explanation of symbols]

10: Fluorescent display tube 12: Phosphor layer 14: substrate 24: Sheet member 26: Opening 30: Grid electrode

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Susumu Sakamoto             2160 Yatsunami, Sanjo, Yasu-cho, Asakura-gun, Fukuoka Prefecture             Address Noritake Electronics Co., Ltd. Yasu Factory             Within F-term (reference) 5C027 BB01 BB03 BB08                 5C036 EE02 EE04 EE14 EF05 EF06                       EF08 EG15 EH01

Claims (10)

[Claims] 1. A plurality of phosphor layers fixed on a plurality of anodes provided on a display surface of a substrate, a filament cathode laid over the phosphor layers, and the phosphor layers and With a plurality of control electrodes provided at a height position between the cathodes, the electrons generated from the filamentous cathodes are controlled by the control electrodes to selectively enter the phosphor layer, A fluorescent display tube of the type that causes a phosphor layer to emit light, wherein a plurality of openings are provided at a plurality of locations above the plurality of phosphor layers, and the respective phosphor layers as a whole are respectively passed through the corresponding openings. A thin plate-shaped thick film dielectric having a predetermined thickness dimension that is observable, and the thin plate-shaped thick film dielectric along the periphery of the plurality of openings to form the plurality of control electrodes. Multiple thick film conductors adhered to the surface of And an electrode, a fluorescent display tube, characterized in that it comprises a sheet member fixed to the display surface of the substrate. 2. The fluorescent display tube according to claim 1, wherein the sheet member is fixed to the display surface of the substrate through a large number of spherical bodies having a predetermined maximum particle diameter. 3. The thick film conductor wiring connected to the thick film conductor electrode is provided on at least one of the inside of the sheet member and one surface thereof facing the display surface.
Alternatively, the fluorescent display tube according to claim 2. 4. A thick film conductor material having a potential approximately equal to that of the filament cathode on a portion of the other surface of the sheet member facing the filament cathode, where the thick film conductor electrode is not provided. The fluorescent display tube according to any one of claims 1 to 3, further comprising a negative electrode. 5. The fluorescent display tube according to claim 1, further comprising an anode and a phosphor layer fixed on the anode on the other surface of the sheet member. 6. A step of providing a plurality of anodes on a display surface of a substrate, a step of fixing a plurality of phosphor layers on the plurality of anodes, and a plurality of steps above the plurality of phosphor layers. The step of providing the control electrode of, and the step of laying the filament cathode above the control electrode, the electrons generated from the filament cathode are controlled by the control electrode to selectively select the phosphor layer. A method for manufacturing a fluorescent display tube in which the phosphor layer is made to emit light by being incident on a plurality of openings, wherein each of the plurality of phosphor layers is entirely corresponding to each opening. A thin plate-shaped thick film dielectric having a predetermined thickness and provided at positions corresponding to the plurality of phosphor layers, each of which has a size observable through Along the perimeter of the opening A sheet member having a plurality of thick-film conductor electrodes fixed to the surface of the thin plate-shaped thick-film dielectric so that the plurality of openings are located above the plurality of phosphor layers. A method of manufacturing a fluorescent display tube, comprising: a sheet member fixing step of fixing the sheet member to a display surface of the substrate. 7. A support preparing step of preparing a support having a film forming surface composed of a high melting point particle layer in which particles having a melting point higher than a predetermined first temperature are bonded with a resin, Dielectric paste for forming a dielectric paste film, in which constituent particles of a thick film dielectric material that can be sintered at one temperature are bonded with a resin, in a pattern corresponding to the thin plate-like thick film dielectric on the film formation surface. A film forming step, and forming a conductor paste film, in which constituent particles of a thick film conductor material that can be sintered at the first temperature are bonded with a resin, in a pattern corresponding to the thick film conductor electrode on the film forming surface. By a conductor paste film forming step and heat treatment of the support at the first temperature,
A step of sintering the dielectric paste film and the conductor paste film without sintering the high melting point particle layer to produce the thin plate-like thick film dielectric and the thick film conductor electrode. The method for manufacturing a fluorescent display tube according to claim 6, wherein the sheet member is manufactured by the method. 8. The method of manufacturing a fluorescent display tube according to claim 7, wherein in the support preparing step, the high melting point particle layer is formed on a surface of a predetermined sheet member manufacturing substrate. 9. The method of manufacturing a fluorescent display tube according to claim 8, wherein the substrate for manufacturing a sheet member does not deform at the firing temperature. 10. The method for manufacturing a fluorescent display tube according to claim 7, wherein the conductor paste film and the dielectric paste film are respectively formed by using a thick film screen printing method.