JP2003263967A - Fluorescent display tube and driving method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fluorescent display tube having a rib-grid structure which enables to realize high luminant luminescence without dim spots by simple controlling, and to provide a driving method thereof. <P>SOLUTION: A plurality of grid electrodes 24 which have three long longitudinal rib members 24y which lie between rows consisting of a plurality of anodes 32, and a plurality of grid electrodes 25 which have two long longitudinal rib members 25y which lie between rows consisting of a plurality of anodes 32, are disposed alternately. An anode wiring group 34 is disposed for each line consisting of a plurality of anodes 32 independently in such a way that seven wiring members 1a, 1b, 1c, 1d, 1e, 1f and 1g of each anode wiring group 34 are disposed also independently one another, wherein anodes 32 of each line and of every seven rows are connected one another with one of the wiring members 1a, 1b, 1c, 1d, 1e, 1f and 1g. An accelerating voltage is applied to grid electrodes 24 and 25 simultaneously, and a positive voltage is applied to wiring members of anode wiring groups 34, with which, prescribed anodes 32 of five rows in the middle of the grid electrodes 24 and 25, are connected. The fluorescent material layers 12 of the five rows are provided with on their both sides at least two long longitudinal rib members 24y and 25y. The fluorescent material layers 12 of the five rows can be luminesced simultaneously without accompanying demerits such as leakage luminescence or dimming because the positive voltage is not applied to the fluorescent material layers 12 of other rows. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a fluorescent display tube and its driving method.

[0002]

2. Description of the Related Art A phosphor layer is fixed on a plurality of anodes provided on a display surface of a substrate, and thermoelectrons generated from a cathode laid above the phosphor layer in a vacuum space are transferred to the phosphor layer and the cathode. There is known a fluorescent display tube of a type in which the fluorescent layer is excited and emits light by being selectively incident on the fluorescent layer by being controlled by a control electrode (grid electrode) provided between and. 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. In particular, in a fluorescent display tube having a rib-grid structure in which the grid electrode is composed of a conductive film fixed to the top of a rib-shaped wall protruding higher than that around the phosphor layer, a mesh covering the phosphor layer is used. -Shaped grid electrode is not used, so display defects such as brightness unevenness and short circuit due to thermal deformation of the grid electrode when the display pattern of the phosphor layer is enlarged are eliminated, and the grid electrode is eliminated. There is an advantage in that the decrease in the brightness of the fluorescent display tube is eliminated in relation to the aperture ratio.

[0003]

By the way, a first direction (for example, a row direction) and a second direction (for example, a column direction) in which a plurality of phosphor layers for forming dot-shaped pixels intersect each other on a substrate. In order to display efficiently and beautifully, the fluorescent display tubes lined up along the line for displaying the anodes are, for example, anode anodes typified by a quadruple matrix type.
It is driven by a multi-matrix method or the like. The applicant of the present application has previously proposed a driving method that suppresses the occurrence of partial shade that occurs when one grid electrode is provided for two rows of phosphor layers. For example, as described in Japanese Patent Application Laid-Open No. 10-105118, there is a driving method of a fluorescent display tube in which, in order to compensate for a shade, auxiliary light emission is performed in addition to main light emission only in a column where the shade is generated.

In the above driving method, when two rows are made to emit light at the same time, the shadow is generated only in the phosphor layer of one row, so that only one of the rows is made to emit auxiliary light. Therefore, in order to obtain a uniform light emission display on the entire surface of the fluorescent display tube, the total light emission amount of the main light emission and the auxiliary light emission in one column is equal to the light emission amount of the other column in which the auxiliary light emission is unnecessary. Therefore, it is necessary to appropriately control the intensity of auxiliary light emission according to the degree of shadow. The above means that the auxiliary light emission must be controlled separately from the main light emission because the appropriate intensity of the auxiliary light emission is usually weaker than that of the main light emission. However, in a normal fluorescent display tube, the outputs of a plurality of grid electrodes and a plurality of anode wirings are mixed and shared by one drive driver, so that an independent drive driver is required for each anode wiring. The driving method of (1) has a problem that the fluorescent display tube (display tube module) including the control device is significantly increased in size and the manufacturing cost thereof is significantly increased.

A pulse corresponding to one main light emission is set to n.
By dividing the data into individual pieces and performing data rewriting n times during one main light emission, the pulse width of the auxiliary light emission can be adjusted in 1 / n steps without separately preparing a drive driver. However, in this case, the number of pulses in one cycle originally required for the number of digits becomes n times, so that there is a problem that the CPU and the driver are required to have extremely high processing speed performance. Further, when the number of digits is very large (for example, about 256 digits), dividing one pulse into n may result in insufficient processing speed of the CPU or the like. In this case, even if you try to lengthen one cycle according to the processing speed, the length is 20 (m
The upper limit of the number of divisions is low, and the practicality of brightness adjustment by pulse division has not been sufficient because it is necessary to be less than about sec) [that is, about 50 (Hz) or more].

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 rib-grid structure capable of obtaining high-luminance light without obscuring by simple control. And to provide a driving method thereof.

[0007]

In order to achieve such an object, the gist of the fluorescent display tube of the first invention is that phosphor layers for forming dot-shaped pixels are provided on the surface. A plurality of anodes, which are fixed and arranged in a first direction and a second direction that intersect with each other on the substrate, are provided, and electrons generated from a cathode installed above the anode in a vacuum space are made incident so that A fluorescent display tube of a type that selectively emits light from a phosphor layer, comprising: (a)
Rib-shaped walls protruding higher than the phosphor layer between the plurality of anodes, and (b) passing between rows of a plurality of anodes arranged in the first direction. A plurality of first control electrodes, each of which is provided on the top of the rib-shaped wall and is connected to a common control electrode wiring, three adjacent to each other, and (c) each of the first control electrodes Control electrode wirings are provided on the top of the rib-shaped wall through the rows of a plurality of anodes arranged along the first direction and adjacent to each other (where n is a natural number) in common. A plurality of second control electrodes each of which is composed of a plurality of electrode parts connected to each other and which are alternately provided with the first control electrodes in the second direction; and (d) an anode along the second direction. M rows (where m = n + 5) are provided electrically independent of each other and the plurality of positive lines are provided. Its second those arranged along the direction of the [m-1] number every plurality of anode wires, which are respectively connected to is to include among the.

[0008]

A second aspect of the present invention, which is intended to achieve the above object, is a method for driving a fluorescent display tube according to the first aspect of the present invention.
(a) Two first control electrodes and one second of the plurality of first control electrodes and second control electrodes that are adjacent to each other
The combination of the control electrodes as one set is sequentially changed along the second direction so that one first control electrode is overlapped, and simultaneously accelerated to the set of the first control electrode and the second control electrode. A scanning step in which a voltage is applied and scanning is sequentially performed;
(b) In synchronization with the scanning timing, the first set of the first set
Within the k-th column located at the center in the second direction of the array of anodes sandwiched between the control electrode and the electrode portion of the second control electrode
(Provided that k = n + 3), a drive voltage is applied to the anode wiring to which a predetermined anode is connected.

[0009]

In this way, the plurality of control electrodes for controlling the electrons are the plurality of first control electrodes having the three electrode portions that pass between the columns of the anodes, and the plurality of first control electrodes. First
A plurality of second control electrodes (hereinafter, collectively referred to as control electrodes unless otherwise specified) provided with n electrode portions that are arranged alternately with the control electrodes and pass through between the columns of anodes. Each anode is connected to every m [m-1] anode wires provided for each row, and the number of anode wires for each row, that is, the multiplicity m is set to [n + 5]. Has been. Therefore, since the relationship between the number n of electrode portions provided in one control electrode and the multiplicity m of the anode wiring is defined as described above, three adjacent control electrodes are set as a set. Considering that, each of the k (= n + 3) rows of anodes located at the center of the row of anodes sandwiched by the plurality of electrode portions has at least two electrodes in the set of control electrodes on both sides in the second direction. There are two electrode portions, and the electrode portions in the pair of control electrodes are connected to the anode wiring different from the adjacent columns of other anodes.

Therefore, by applying an accelerating voltage to the set of control electrodes and a driving voltage to the anode wiring to which the k-th column anodes are connected, the accelerating voltage is applied to the k-th column anodes. While at least two electrode portions of the control electrode to which is applied are provided, the driving voltage is not applied to the anodes of the columns connected to the different anode wirings, which causes inconveniences such as leakage light emission and shade. The k rows can be simultaneously made to emit light. At this time, if two sets are sequentially changed so that one first control electrode overlaps along the second direction, a similar positional relationship is always provided between the control electrode and the anode. Since all the columns are satisfied and all the columns correspond to the above-mentioned column k in sequence, all the columns of the anodes can emit light. Therefore, the brightness of the fluorescent display tube is increased in accordance with the number k of rows that emit light at the same time. The other column of anodes connected to the same anode wiring as the column of anodes to be made to emit light cannot be made to emit light by applying a negative control voltage to the electrode part (control electrode) adjacent to it. . That is, only the above-mentioned row k is made to emit light without shadow, and the rows of other anodes are not made to leak and emit light. Moreover, in the above-described driving method, the pulse width and potential of the driving pulse applied to the anode wiring may be constant, and the number of driving voltages applied at the same time is kept at k, which makes driving particularly complicated. In addition, since each of the control electrodes is composed of n electrode parts electrically connected to each other, the control electrodes are driven separately as compared with the case where each is composed of one electrode. The number is reduced to 1 / n, and drive control of the control electrode becomes easy. From the above, it is possible to obtain light emission of high brightness without shadow by simple control.

Incidentally, in the past, when determining the number of electrode parts constituting each control electrode, the multiplicity of anodes, or the number of rows of anodes that emit light at the same time, their mutual relation was not particularly considered. In the anode multi-matrix drive for increasing the brightness by simultaneously emitting light from a plurality of columns of anodes, it is necessary to multiplex the anode wiring, but generally, the number of common electrode portions is large and the multiplicity of the anode wiring is small. The more the number of ports required for the drive controller is reduced, which is preferable in terms of manufacturing cost. However, the relationship between these numbers is contradictory. The present inventor has studied a driving method and a control electrode structure and an anode wiring structure suitable for the driving method in order to reduce the number of ports as much as possible under the contradictory relationship,
It has been found that the number of electrode parts and the multiplicity of anode wiring may be set in the above relationship. The present invention has been made based on such knowledge.

[0012]

Another aspect of the present invention is preferably a plurality of first control electrodes and a plurality of second control electrodes, each of which has a plurality of electrode portions arranged in the first direction. The anodes are connected to each other to form a lattice. In this way, each of the plurality of anodes in each column is surrounded by the electrode portion of the control electrode, so that when the electrode portion of the control electrode is composed of only the portion passing between the columns of anodes. Compared with this, there is an advantage that the luminance is increased and the luminance unevenness hardly occurs.

Further, preferably, the fluorescent display tube is (e)
One first control electrode is a combination of two first control electrodes and one second control electrode that are adjacent to each other among the plurality of first control electrodes and second control electrodes. A control electrode driving device for sequentially applying a accelerating voltage to the set of the first control electrode and the second control electrode at the same time while sequentially changing while sequentially changing along the second direction. f) Synchronized with the timing of the scan, k located in the center in the second direction of the row of anodes sandwiched by the electrode portions of the pair of first control electrodes and second control electrodes.
An anode drive device for applying a drive voltage to the anode wiring to which a predetermined anode in a row (where k = n + 3) is connected,
It includes a drive control device. The drive method as described above is preferably realized by including such a drive control device.

[0014]

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, for example, a substrate 14 made of an insulating material such as glass, ceramics, enamel, etc., provided with a large number of dot-shaped pattern phosphor layers 12 on one surface, and a glass formed in a frame shape. Spacer 16, a transparent cover glass plate 18, and a plurality of anode terminals 20 _P ,
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 glass-sealed to each other,
A vacuum space surrounded by these members is formed.

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 large number of dot-shaped phosphor layers 12 on the display surface 22 have polygonal shapes similar to each other, for example, each side along the longitudinal direction of the substrate 14 and the width direction substantially orthogonal thereto is 400. It has a square shape of about (μm) and is provided with a constant center interval in the two directions. Further, on the display surface 22, a plurality of grid electrodes 24 and 25 having a substantially lattice shape are formed on the display substrate 22.
4 are alternately provided in the longitudinal direction, and each of the individual phosphor layers 12 is surrounded by the grid electrodes 24 and 25 over substantially the entire circumference thereof.

Further, a pair of filament supporting frames 26 (only one of which is located on the right side in the figure) having the cathode terminal 20 _K is fixedly provided on both ends of the substrate 14, respectively. A plurality of thin filaments (filament cathodes) 28 functioning as a direct heating type cathode (cathode) are provided between the support frames 26 in parallel with the longitudinal direction of the substrate 14 and apart from the display surface 22. It is stretched to the height position. Note that the fluorescent display tube 10 is provided with an exhaust hole for exhausting and sealing the inside of the vacuum container, a getter for maintaining the internal vacuum degree after sealing, etc. Omitted.

FIG. 2 is an enlarged perspective view showing a part of the display surface 22 of the substrate 14 described above. As shown in the figure, on the display surface 22, a rib-shaped wall 30 having a lattice shape as a whole is provided in a protruding manner so as to substantially contact and surround the outer peripheral edge of each phosphor layer 12. That is, it is erected in the direction away from the substrate 14, that is, in the direction toward the filament 28 side. The rib-shaped wall 30 is made of, for example, an insulating material such as low melting point glass containing an inorganic filler such as alumina particles, and has a width dimension of about 60 to 150 (μm),
The height dimension is higher than the surface of the phosphor layer 12, for example, 60 to 30
It is about 0 (μm). The grid electrodes 24 and 25 are
A thick film conductor containing a particulate conductive material such as particulate graphite, silver, palladium, copper, aluminum or nickel as a main component, and 5 to 50 (μm) on the top of the rib-shaped wall 30.
The thickness is about 20 μm, for example. That is, in the present embodiment, the control electrode is provided in the rib-grid structure in which the grid electrodes 24 and 25 are provided on the top of the rib-shaped wall 30. Grid electrodes 24, 25
Is insulated from the phosphor layer 12 by the rib-shaped wall 30 and is located at an intermediate height position between the phosphor layer 12 and the filament 28.

The plurality of grid electrodes 24,
Each of the 25 includes a substrate 1 as shown in FIG. 1 above.
4. Longitudinal portions 24y and 25y which have a longitudinal shape extending along the short side direction (Y direction) of 4 and pass between the plurality of phosphor layers 12 arranged along the longitudinal direction of the substrate 14, and It is composed of branch portions 24x, 25x protruding from both sides in the lateral direction (X direction) from a plurality of positions in the middle of the longitudinal portions 24y, 25y. The center interval in the longitudinal direction of the longitudinal portions 24y, 25y of the plurality of branch portions 24x, 25x is constant. In addition, the branch portion 24x is continuous in the X direction by connecting those extending from the three longitudinal portions 24y adjacent to each other, and the branch portion 25x has two longitudinal portions 25y adjacent to each other. Those extending from are connected in the X direction by being connected to each other. That is, the branch portion 24
The x and the branch portion 25x are not connected to each other, and the grid electrodes 24 and 25 are provided as a whole intermittently in the X direction. Therefore, the three longitudinal portions 24y to which the branch portions 24x are connected are electrically connected to each other, and the branch portions 25
The two elongated portions 25y in which x is connected to each other are electrically connected to each other, and each of the grid electrodes 24 and 25 is
Three or two longitudinal portions 24y, 25y and phosphor layer 1
2, a plurality of branch portions 24x corresponding to the number in the Y direction,
25x and a grid shape. The grid electrode 2
4, 25, the branch portions 24x and 25x are, for example, d _G = 100.
They are electrically isolated from each other by being separated from each other by a small amount (μm). In this embodiment, the short side (Y) direction of the substrate 14 is the first direction
The (X) direction corresponds to the second direction, and the two directions are orthogonal to each other. The grid electrode 24 corresponds to the first control electrode and the grid electrode 25 corresponds to the second grid electrode.

Therefore, each of the many phosphor layers 12 is
The two longitudinal portions 24y or 25y located on both sides in the longitudinal direction of the substrate 14 and the two branch portions 24x or 25x located on both sides in the short side direction, that is, the constituent portion of the grid electrode 24 or 25. The whole circumference is surrounded by. However, the grid electrode 2
The phosphor layer 12 located at the boundary between the four and the twenty-five is composed of the longitudinal portions 24y and 25y adjacent to each other and a plurality of branch portions 24x and 2x extending from the longitudinal portions 24y and 25y toward each other.
5x and are surrounded by those branches 24x, 25
The enclosing method is incomplete because x is separated from each other by d _G. In addition, since the phosphor layer 12 is provided in the region surrounded by the grid electrodes 24 and 25 in close contact with the inner peripheral edge thereof, the phosphor layer 12 is
The mutual spacing d _A of the grid electrodes 24, 25
It is equal to the width dimension of 4y, 25y and the branch portions 24x, 25x, and is, for example, about 60 to 150 (μm). Also, the rib-shaped wall 3
The plane shape of 0 is the same as the plane shape of the grid electrodes 24 and 25 fixed thereon, as shown in FIG. 2, for example, and is composed of a longitudinal portion 30a and a branch portion 30b.

As shown in the partial cross-sectional structure of FIG. 2, a plurality of anodes 32 each having a substantially rectangular shape are provided below the phosphor layer 12 on the display surface 22. ing. The anode 32 is composed of a graphite layer having a thickness of, for example, about 30 to 40 (μm). The plurality of phosphor layers 12 are fixed on the anode 32, respectively, and the length dimension of each side of the anode 32 is about 400 (μm), that is, the same dimension as the phosphor layer 12 and It has a shape. The rib-shaped walls 30 are provided so as to protrude between the anodes 32, and the anodes 32 are divided into the rib-shaped walls 30 on the substrate 14 so that they are independent of each other, that is, electrically connected to each other. Insulated state.

The phosphor layer 12 is provided with one or several kinds of phosphors corresponding to a desired emission color for each anode 32, and the thickness dimension thereof is determined for each emission color. For example, it is about 30 (μm). When a plurality of types of phosphors are used, for example, in a color display using three colors of RGB, for example, RG is sequentially arranged for each row along the longitudinal direction of the substrate 14.
Phosphor layers 12 corresponding to the three colors of B are provided to form a stripe arrangement, or 4 rows of 2 columns × 2 columns adjacent to each other.
The phosphor layers 12 corresponding to the four colors of RGGB are provided in an individual unit to form a quartet arrangement. One pixel of the fluorescent display tube 10 has three or four different emission colors arranged adjacent to each other in a stripe shape or a rectangular shape (however, in the case of four, two of them have the same emission color). It is composed of the phosphor layer 12.

FIG. 3 is a view for explaining the electrode structure on the substrate 14 in a sectional view taken along line III-III in FIG. 2, that is, in a widthwise sectional view at an arbitrary position in the longitudinal direction of the substrate 14. On the display surface 22 of the substrate 14, a thick film conductor paste is printed by a screen printing method or the like in a thickness of about 15 (μm) and baked, or by vapor deposition and etching treatment of an aluminum thin film or the like, a plurality of anode strips 34 are formed so as to be connected to the anode terminal 20 _P. On this anode wiring 34, an insulator layer 38 is fixedly formed so as to cover substantially the entire surface of the display surface 22 and has a through hole 36 penetrating in the thickness direction. The insulator layer 38 is formed, for example, by applying a thick film insulating paste composed of a low melting point glass and a coloring pigment to a thickness of about 30 to 40 (μm) by a screen printing method and baking the paste. .

The anode 32 is provided on the insulating layer 38 at a position electrically connected to the anode wiring 34 through the through hole 36. The anode 32 is formed by printing a thick film printing paste containing graphite as a main component in a predetermined dot pattern and firing the paste. The phosphor layer 12 is formed by printing a thick film phosphor paste on the anode 32. Further, the rib-shaped wall 30 is formed by printing a thick film insulating paste around the phosphor layer 12 and the anode 32. That is, it is erected on the insulator layer 38, not directly on the substrate 14. The rib-shaped wall 30 is formed by laminating a thick film insulating paste made of an insulating material such as low melting point glass or an inorganic filler in a predetermined pattern having a line width of 60 to 150 (μm) repeatedly. Insulator layer 3
It has a height of about 60 to 300 (μm), for example, about 200 (μm) from the surface 8 and a height of about 30 to 250 (μm) from the surface of the phosphor layer 12. The grid electrode 24 includes silver, palladium, aluminum, on the top of the rib-shaped wall 30,
The thick film conductor paste containing a particulate conductive material such as nickel or carbon is fixedly formed by printing with a thickness of about 5 to 50 (μm).

The plurality of anode wirings 34 are provided along the longitudinal direction of the substrate 14, for example, and each of the plurality of anodes 32, that is, each of the phosphor layers 12 is
Substantially aligned ones in the width direction of the substrate 14 are respectively connected to a large number of anode wirings 34 provided in each row along the longitudinal direction so as to be electrically independent from each other. In Figure 4,
The connection state of the first row of the anodes 32 located on the uppermost side in the figure is schematically shown. In FIG.
The anode wiring 34 includes seven lines a to g which are independent from each other in each row of the anode 32, for example, 34-1a and 34-1 for the first row.
b, to 34-1g are provided, and the plurality of anodes 32 in each row are connected to a common one of the seven anode wirings 34 at intervals of six. That is, in the present embodiment, the substrate 14 is configured to have an anode 7-layer wiring structure, and the anode 32 connected to any of the 7 anode wirings 34 is in the longitudinal direction of the substrate 14, that is, left and right in the drawing. They are lined up at regular intervals in the direction. The connection state with the anode wiring 34 is the same for any row of the other anodes 32 not shown. The anode multiplicity, that is, the number m of the anode wirings 34 in each row is one grid electrode 25.
When the number of the longitudinal portions 25y provided in the above is set to n, it is determined to satisfy the following formula (1), and in this embodiment, n = 2 and therefore m = 7. In addition, in FIG. 4, for convenience of illustration, the anode 32 and the grid electrode 24,
Although it is drawn so that it does not touch 25, the display surface 22
This may be the actual arrangement state in. m = n + 5 (1)

Further, in FIG. 4 described above, the fluorescent display tube 1
0 is provided with a control circuit connected via a terminal 20 or integrally formed on the substrate 14, and each of the plurality of grid electrodes 24 and 25 is connected to a grid via a grid wiring (not shown). -The output ports of the driver 40 are independently connected. Also, the anode 3 of each row
Seven anode lines 34 are provided in each row in which every six lines 2 are connected, and are independently connected to the output port of the anode driver 42. The grid driver 40 and the anode driver 42 are controlled according to the output signals of the controller 44, and are driven as described later according to the data input to the controller 44. In this embodiment, the grid driver 40 serves as a control electrode driving device,
The anode driver 42 corresponds to the anode driving device. The controller 44 includes ROM, RAM, C
It is composed of a PU, an I / O, a converter and the like.

When the fluorescent display tube 10 constructed as described above is driven, two grid electrodes 24 adjacent to each other in a state where a predetermined heating current is constantly applied to the plurality of filaments 28. Also, one grid electrode 25 is set as a set, and a relatively positive acceleration voltage of, for example, about 20 (V) is sequentially applied to the zero (V) filament 28, and scanning is performed thereon. Then, in synchronization with the scanning timing, a positive drive voltage of, for example, about 20 (V) with respect to the cathode potential is applied to the desired anode wiring 34. As a result, the thermoelectrons emitted from the filament 28 are accelerated by the grid electrodes 24 and 25 to which a positive voltage is applied, so that a positive voltage is also applied to the phosphor layer 12 surrounded by the positive electrodes via the anode 32. Then, 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, the grid electrodes 24 and 25 that surround the phosphor layer 12 are several times larger than the filament 28.
When a negative cutoff bias of about (V) is applied, thermoelectrons do not reach the phosphor layer 12 and the phosphor layer 12 does not emit light. Therefore, in a state where the thermoelectrons are emitted by the current flowing through the filament 28, a desired one of the phosphor layers 12 of each of the phosphor layers 12 is synchronized with the timing at which the acceleration voltage is sequentially applied to the grid electrodes 24 and 25. When a positive voltage is applied to an object, light emission display is performed in a desired pattern by so-called dynamic driving.

FIG. 5 showing driving voltage waveforms to the grid electrodes 24 and 25 and the anode wiring 34, and a voltage application state to the grid electrodes 24 and 25 and a lighting state of the phosphor layer 12 at a specific time are shown below. The driving method of the fluorescent display tube 10, that is, the control of the controller 44 will be described in detail with reference to FIGS. 6 (a) to 6 (c). In FIG. 5, “... Gi, Gj, to Gn ...” represent grid electrodes 24 and 25 sequentially arranged in the row direction, and “...
"Arc, Ard, ~ Asc ..." Represents seven anode wirings a, b, ~ g provided in each "... r row, s row ...". In addition, in FIGS. 6A to 6C, “I, J, ..., X” indicates a row of the phosphor layers 12,
“R, s, ...” represents a row of the phosphor layer 12, and “a, b, to g” written in □ indicates that the anode 32 below the phosphor layer 12 in each row. This shows the distinction between the seven connected anode wirings 34. Also, at each time t1
At t3 to t3, “◯” indicates that the accelerating voltage is applied to the grid electrode 24 or the grid electrode 25 shown thereon, and “●” indicates that the cutoff bias is applied.

At time t1, the grid electrodes 24,
An acceleration voltage is applied to three of Gi, Gj, and Gk of 25, and Arc, Ard, Are, and A of the anode wiring 34 are applied.
A positive voltage is applied to rf, Arg, Asc, etc., that is, five subscripts c, d, e, f, and g out of seven in each row.
Therefore, the electrons generated from the filament 28 are attracted to the three grid electrodes 24 and 25 to which the accelerating voltage is applied. Since a positive voltage is not applied to the I, J, P, and Q columns of the body layer 12, electrons are not directed to the phosphor layers 12 of these four columns and cannot emit light. On the other hand, since a positive voltage is applied to the K, L, M, N, and O columns, the attracted electrons are directed toward the phosphor layers 12 in those five columns, and the phosphors are caused by the incident electrons. It is excited and emits light. In FIG. 6B, the phosphor layer 12 emitting light at this time t1 is shown in white. In this figure, the shaded phosphor layer 12 does not emit light because a positive voltage is not applied to the anode 32. Also, the phosphor layer 12 marked with X does not emit light because it is surrounded by the grid electrodes Gl, Gm, Gn, etc. to which the positive voltage is applied to the anode 32 but the cutoff bias is applied. Is.

That is, at time t1 above, the total is 3
By applying an accelerating voltage to the individual grid electrodes 24, 25 at the same time, a total of eight longitudinal portions 24y,
Nine rows of phosphor layers 1 sandwiched or adjoined by 25y
Of the two, K, L, M, which are located in the center in the row direction,
Five columns of N and O are selected as columns to emit light, and a positive voltage is applied only to the phosphor layer 12 of the row to emit light according to the input data among the five columns. Therefore, among the seven anode wirings a to g in each row, the positive voltage is actually applied to those that are connected to the phosphor layers 12 in the K, L, M, N, and O columns to emit light. Only. The waveform in the column of the anode wiring in FIG. 5 indicates that a positive voltage or a cutoff bias is applied depending on the data. In this embodiment, the number k of columns of the phosphor layer 12 that emits light at the same time, that is, the anode wiring 34 of each row.
Of these, the number to which the drive voltage is applied is 5, and the relationship is k = n + 3 with respect to the number n of the longitudinal portions 25y provided in the grid electrode 25.

At time t2, the grid electrodes Gi, G
While the cutoff bias is applied to j, the acceleration voltage is applied to the grid electrodes Gl and Gm, and the anode wirings Arc, Ard, Are, Asa, Asb, Asc, etc. A positive voltage is applied to the five lines a, b, c, d, and e. Therefore, during the period from time t2 to t3, the three grid electrodes 2 to which the acceleration voltage is applied are applied.
Of the phosphor layers 12 in nine rows N to V surrounded by or adjacent to Nos. 4 and 25, P located at the center thereof,
5 columns of Q, R, S and T are selected as columns to emit light,
Of the phosphor layers 12 in the row, a predetermined one according to the data is made to emit light. FIG. 6C shows the selected state of the grid electrodes 24 and 25 and the light emitting state of the phosphor layer 12 at this stage.

At time t3, similarly, this time, the grid electrodes Gm, Gn, Go (Go is not shown) are similarly provided.
The accelerating voltage is applied to the
When a positive voltage is applied to Arg, Asa, Asb, etc., that is, the five subscripts f, g, a, b, and c among the five subscripts in each row, the phosphor layers 12 in five columns below U emit light. To be made.

Thus, in this embodiment, two grid electrodes 24 and 1 which are adjacent to each other in the row direction are provided.
One grid electrode 25 is set as one set, and while changing the combination one by one in the row direction, an acceleration voltage is simultaneously applied to the one set of grid electrodes 24 (that is, two grid electrodes 24 are selected at a time). Then, the acceleration voltage is applied while shifting the selected combinations one by one), and the phosphor layer 12 (anode 32) is surrounded by the grid electrodes 24 to which the acceleration voltage is applied and is placed at the center in the row direction. By applying a positive voltage to the anode wiring 34 to which a predetermined one of the three columns located is connected, the phosphor layers 12 of each column are sequentially caused to emit light.

In short, in the fluorescent display tube 10 of the present embodiment, a plurality of grid electrodes 24 each having three longitudinal portions 24y passing between the rows of the plurality of anodes 32, and the grid electrodes thereof. The grid electrode is composed of a plurality of grid electrodes 25, each of which is provided with two longitudinal portions 25y which are arranged alternately with 24 and which pass between the rows of a plurality of anodes 32, and the anode wiring 34.
In each of the rows, a plurality of anodes 32 are electrically isolated from each other, and every six rows of the anodes 32 are connected to each other. Therefore, the central 5 rows of the phosphor layers 12 surrounded by the two grid electrodes 24 and the one grid electrode 25 adjacent to each other are provided on both sides of the substrate 14 in the longitudinal direction. Grid electrode 2
At least two of the longitudinal portions 24y and 25y forming the reference numerals 4 and 25 are positioned, and the phosphors in the other rows surrounded by or adjacent to the pair of grid electrodes 24 and 25. It is connected to the anode wiring 34 different from the layer 12. Therefore, by simultaneously applying an acceleration voltage to the pair of grid electrodes 24 and 25, and by applying a positive voltage to the anode wiring 34 to which the predetermined anodes 32 in the central five columns are connected, The five rows of phosphor layers 12 (anode 32) are provided with at least two longitudinal portions 24y, 25y to which an acceleration voltage is applied.
Will be provided on both sides thereof, while a positive voltage is not applied to the phosphor layers 12 in the other columns,
The phosphor layers 12 in the above five rows can be made to emit light at the same time without any inconvenience such as leakage light emission and shadow.

At this time, when the above-mentioned combination of two sets is shifted by two along the longitudinal direction of the substrate 14 so that one grid electrode 24 overlaps, the grid electrodes 24 and 25 and the phosphor layer 12 (anode) are formed. 32), the above-mentioned positional relationship is always established, and all the rows of the phosphor layers 12 correspond to the above-mentioned “central five rows”. Therefore, all the rows of the phosphor layers 12 Can be similarly illuminated. Therefore, according to the number of columns (5) that emit light at the same time, the luminance is five times that obtained when only one column emits light at a time. In addition, the phosphor layers 12 in the other columns connected to the common anode wiring 34 with the phosphor layers 12 in the five columns to be made to emit light have longitudinal portions 24y, 25y (the grid electrodes 24, 2y) adjacent thereto.
Since a cutoff bias is applied to the component 5), no light is emitted. On the other hand, the five rows of phosphor layers 12 that are to emit light include at least two elongated portions 24y,
Since 25y is provided on both sides thereof, the influence of the negative electric field formed by the grid electrodes 24 and 25 to which the cutoff bias is applied is preferably eliminated. Therefore, no leakage light emission or shadow occurs.
In the present embodiment, the step of sequentially applying the accelerating voltage to the grid electrodes 24 and 25 in groups of three as described above to sequentially scan is the "scanning step", and the selected grid electrode 2
The step of applying a positive voltage to the anode wiring 34 corresponding to Nos. 4 and 25 corresponds to the “step of applying a driving voltage”, respectively.

Further, in this embodiment, the grid electrode 24 has three longitudinal portions 24y electrically connected to each other, and the grid electrode 25 has two longitudinal portions 25y electrically connected to each other. Since it is provided, the number of grid electrodes is two fifths as compared with the case where the longitudinal portions 24y and 25y are provided as independent grid electrodes. Therefore, there is an advantage that the required number of ports of the grid driver 40 is small.

Further, the driving voltage waveform applied to the seven anode wirings 34 provided in each row of the phosphor layer 12 (anode 32) has a pulse width and a pulse width which are apparent from the explanation of the driving method and FIG. Since the potentials are similar to each other, the waveforms applied to any of the anode wirings 34 are the same drive waveforms except that the phases are different, and moreover, the number of simultaneously applied voltages is kept at k = 5, There is an advantage that the brightness can be increased without complicating the driving.

The number of driver ports required for the fluorescent display tube 10 is actually the total number required to drive the grid electrodes 24 and 25 and the number required to drive the anode wiring 34. When the number of columns of the phosphor layer 12 is C and the number of rows is L, the required port number P is given by the following equation (2). That is, when the number of required ports P calculated in this way is smaller than that of other anode substrate configurations capable of obtaining a desired brightness, the value of adopting the configuration of the present embodiment is high. . For example, the number of columns C is sufficiently larger than the number of rows L. In the present embodiment, the number of the longitudinal portions 25y provided in each of the grid electrodes 25 is n = 2, and the multiplicity of the anode wiring 34 is m = 7. Is obtained. P = [2C / (3 + n)] + (L × m) ・ ・ ・ (2) P = [2C / (3 + 2)] + (L × 7) ・ ・ ・ (3)

In this embodiment, n = 5 at the same time.
The multiplicity m of the anode wiring 34 was set to 7 for the purpose of causing the column to emit light. Similarly, in a structure in which a mesh-shaped grid electrode is provided between the phosphor layer 12 and the filament 28, if five rows are simultaneously made to emit light, the multiplicity is set to prevent leakage light emission due to the wraparound of electrons. Must be set to at least 9. Therefore, according to the present embodiment, there is an advantage that a relatively small multiplicity is sufficient to obtain similar brightness.

As a result, the required number of ports is reduced as compared with the case where a mesh-shaped grid electrode is used, and the number of anode wirings 34 passing between the anodes 32 is reduced, so that the phosphor layer is formed. There is also an advantage that the dot pitch of 12 can be reduced. Even if the arrangement pitch of the anode wirings 34 is made small, there is a lower limit determined by the pattern forming technology and the demand for ensuring mutual insulation. Therefore, the minimum value of the dot pitch of the phosphor layer 12 is limited according to the number of arranged phosphor layers.

Next, another embodiment of the present invention will be described. In the following examples, the structural difference from the above-described examples is that the longitudinal portion 25 provided in the grid electrode 25 is provided.
Since only the number n of y and the multiplicity m of the anode wiring 34 are,
These values and the difference in driving based on them will be mainly described.

FIG. 7 is a schematic diagram for explaining the structure of an anode substrate of a fluorescent display tube of another embodiment, and corresponds to FIG. 6 described above. In FIG. 7 (a), the grid electrodes 25 (..., Gj, G1, ...) Are each provided with three elongated portions 25y, which are electrically connected to each other by the branch portions 25x. There is. That is, in the present embodiment, the number of the elongated portions 24y and 25y provided on the grid electrodes 24 and 25 is the same. In addition, each line of the phosphor layer 12 has 8
Book-like anode wirings 34a to 34h are provided, and each of the phosphor layers 12 has an anode wiring 34a,
34b, to 34h. That is, in this embodiment, the number n of the longitudinal portions 25y provided in one grid electrode 25 is n = 3, and the multiplicity of the anode wiring 34 is m = 8. These relationships also follow the above-mentioned equation (1).

Even when the grid electrode 24 and the anode wiring 34 are configured as described above, when driving,
As shown in FIG. 8, an acceleration voltage is applied to two grid electrodes 24 and one grid electrode 25 adjacent to each other at the same time, and the central six columns of the phosphor layers 12 surrounded by them, that is, A positive voltage is applied to a number of columns that is larger than the number n of the longitudinal portions 25y provided in each of the grid electrodes 25 by 3, and the combination of the grid electrodes 24 and 25 is set so that only one grid electrode 24 overlaps. A positive voltage is applied to the corresponding anode wiring 34 while shifting each piece.

Therefore, at time t1, the acceleration voltage is applied to the grid electrodes Gi, Gj, and Gk, and the six anode wirings 34c, 34d, 34e, and 34 are formed.
By applying a positive voltage to f, 34g, and 34h,
A desired one of the phosphor layers 12 in rows K to P is made to emit light (see FIG. 7B). Among the columns of the phosphor layer 12 surrounded by or adjacent to the grid electrodes Gi and Gk, no positive voltage is applied to the I column, J column, Q column, and R column, so that the acceleration voltage is applied to the grid electrodes Gi and Gk. They do not emit light when applied. In addition, the anode wiring 34
Other columns connected to c, 34d, 34e, 34f, 34g, and 34h, for example, the phosphor layers 12 in the columns S to X, etc., also have the cutoff bias applied to the grid electrode Gl and the like. Can't emit light. Grid electrode Gk
The same applies at the next timing when the accelerating voltage is applied to Gm to Gm, and the columns Q to V are simultaneously made to emit light as shown in FIG. 7C.

That is, also in the present embodiment, the number of the elongated portions 24y forming the grid electrode 24 is set to 3, and the number n of the elongated portions 25y forming the grid electrode 25 and the multiplicity of the anode wiring 34. The relationship with m is determined as described above, and the accelerating voltage is applied to the two grid electrodes 24 and the one grid electrode 25 adjacent to each other as a set, and at the same time, the accelerating voltage is applied. Since the positive voltage is applied to the central six columns among the columns of the phosphor layers 12 surrounded by one set, the phosphor layers 12 in the six columns are made to emit light at the same time without leakage light emission. As a result, 6 times higher brightness can be obtained as compared with the case where each column is made to emit light at different timings. At this time, for any row of the phosphor layers 12 to emit light,
Since at least two longitudinal portions 24y and 25y to which an accelerating voltage is applied are provided on both sides, the influence of the negative electric field formed by the other grid electrodes 24 and 25 to which the cutoff bias is applied is surely eliminated. That is, light is emitted at a uniform brightness without causing a shade in any of a plurality of rows that are made to emit light at the same time.

Further, in this embodiment, the grid electrodes 24,
The number of 25, that is, the number of ports required for the driver 40 is
In the equation (2), if n = 3 and m = 8, P = (C /
3) + (L × 8) Therefore, FIG.
It can be said that the value of adopting such a structure is enhanced when the number L of rows is smaller than the number C of columns as compared with the case shown in FIG.

In this embodiment also, the anode wiring 34 is used.
The pulse width and potential of the drive waveform applied to the
Similar to the above-described embodiment, a drive pulse having a similar waveform is applied to any of the wirings 34 only with a different phase.

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

For example, in the above-described embodiment, the combination of the number n of the longitudinal portions 25y provided in the grid electrode 24 and the multiplicity m of the anode wiring 34 is (2, 7) and
Although the case of (3, 8) has been described, the values of n and m are weighed by comparing the desired brightness and the value of the number of ports P calculated based on the actual values of C and L, In order to obtain as high brightness as possible within the range of the required number of ports allowed,
It is appropriately determined within the range that satisfies the above formula (1). That is,
When n is set to 4, if m is set to 9, and if n is set to 5, m is set to 10, the same drive as in each of the above-described embodiments is possible, and the effect of the present invention is enjoyed. obtain.

In the embodiment, the case where the present invention is applied to the fluorescent display tube 10 in which a plurality of square phosphor layers 12 are arranged in two directions orthogonal to each other has been described. The same applies to a fluorescent display tube in which the first direction and the second direction are not orthogonal to each other, such as when hexagonal phosphor layers are closely arranged.

Further, in the embodiment, each of the plurality of grid electrodes 24 and 25 has a grid shape, but it is possible to simultaneously apply the acceleration voltage by connecting to the common grid electrode wiring. Display surface 2 if configured
It does not matter if the fluorescent substance layer 12 on the upper part 2 is not electrically connected. In such a configuration, the branch portions 24x and 25x are not essential and the grid electrode 24,
25 may have a stripe shape.

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

[Brief description of drawings]

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

FIG. 2 is an enlarged perspective view showing a part of a display surface of the fluorescent display tube of FIG.

3 is a diagram illustrating a structure of a substrate in a cross section taken along line III-III in FIG.

FIG. 4 is a diagram illustrating a main part of a control configuration of the fluorescent display tube in FIG.

5 is a driving waveform diagram showing an example of a driving method of the fluorescent display tube of FIG. 1. FIG.

6 (a) to 6 (c) are diagrams for explaining voltage application and light emission states at specific times in FIG.

7 (a) to (c) are diagrams corresponding to FIGS. 6 (a) to 6 (c) for explaining a configuration and a driving method of a fluorescent display tube according to another embodiment of the present invention.

8 is a diagram corresponding to FIG. 5 for explaining an example of a drive waveform of the fluorescent display tube configured as shown in FIG. 7.

[Explanation of symbols]

10: Fluorescent display tube 12: Phosphor layer 14: substrate 24: Grid electrode (control electrode) 32: Anode 34: Anode wiring 40: Grid driver 42: Anode driver

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) G09G 3/20 642 G09G 3/20 642A 642D 3/30 301 3/30 301 (72) Inventor Mohri Jun Fukuoka 2160 Yatsunami, Asakura-machi, Asakura-gun, Akita-gun Address No. 2160, Noritake Electronics Co., Ltd. F-term (reference) in Yasu factory 5C036 EE02 EF02 EF06 EF09 EG15 EG29 EG31 EG47 EG48 EH04 5C080 AA08 BB05 CC01 CC03 DD05 DD30 DD26 EE18EE FF10 HH18 HH19 JJ02 JJ04 JJ06 KK20 KK21 KK43

Claims (4)

[Claims] 1. A phosphor layer for forming a dot-shaped pixel is fixed to each surface, and a plurality of anodes are arranged along a first direction and a second direction intersecting each other on a substrate, A fluorescent display tube of a type that selectively emits light from the phosphor layer by allowing electrons generated from a cathode installed above it in a vacuum space to enter, and the fluorescent display is provided between the plurality of anodes. The rib-shaped wall protruding higher than the body layer and a row of a plurality of anodes arranged in the first direction are provided between the rib-shaped walls and the tops of the rib-shaped walls and are adjacent to each other. Between a plurality of first control electrodes, each of which is composed of a plurality of electrode portions, each of which is connected to a common control electrode wiring, and a plurality of anodes, which are arranged in the first direction. Through the top of the ribbed wall Of the plurality of electrodes, each of which is connected to a common control electrode wiring and has n electrodes adjacent to each other (where n is a natural number), and alternates with the first control electrode in the second direction. A plurality of second control electrodes, and m electrodes for each row of the anodes along the second direction (where m = n +
5), which are electrically independent of each other and which are arranged along the second direction among the plurality of anodes are [m−1]
A fluorescent display tube comprising: a plurality of anode wirings connected to every other piece. 2. The plurality of first control electrodes and the plurality of second control electrodes are continuous with each other through a plurality of anodes, each of which has a plurality of electrode portions arranged in the first direction. The lattice shape is formed by being made to move.
Fluorescent display tube. 3. A combination of two adjacent first control electrodes and one second control electrode of the plurality of first control electrodes and second control electrodes, which are adjacent to each other, as one set. A control electrode for sequentially applying a accelerating voltage to a set of the first control electrode and the second control electrode at the same time while sequentially changing the first control electrode so as to overlap with each other in the second direction. Within the k row located in the center in the second direction among the rows of anodes sandwiched by the drive device and the scanning timing thereof, between the pair of first control electrodes and the second control electrodes. 3. The fluorescent display tube according to claim 1, further comprising a drive control device including an anode drive device for applying a drive voltage to the anode wiring to which a predetermined anode of (where k = n + 3) is connected. 4. The method of driving a fluorescent display tube according to claim 1, wherein the first control electrode and the second control electrode are two adjacent first electrodes. While sequentially changing the combination of the control electrode and the one second control electrode as one set along the second direction so that the one first control electrode overlaps, the one set of the first control electrodes And a scanning step of sequentially applying an accelerating voltage to the second control electrode and sequentially scanning, and in synchronism with the timing of the scanning, the electrodes are sandwiched between the pair of the first control electrode and the second control electrode. A step of applying a drive voltage to the anode wiring to which a predetermined anode in the row k of the anodes located in the center in the second direction (where k = n + 3) is connected. Driving method for fluorescent display tube.