JPS6329749B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an X-Y matrix fluorescent display tube that can eliminate leakage light without increasing the number of terminals.

FIG. 1 is a schematic diagram showing a conventional X-Y matrix fluorescent display tube. To simplify the explanation, a case where the number of display dots is five will be shown, for example. In the figure, 1 is a cathode, 2a to 2e are grid electrodes to which grid driving pulses shown in FIGS. 2a to 2e are applied, and 3a to 3e are anodes shown in FIGS. 3a to 3e, respectively. A driving pulse is applied to each anode electrode coated with a phosphor.

In the X-Y matrix fluorescent display tube with this structure, a plurality of grid electrodes 2a to 2e are arranged in parallel in the X-axis direction, and a plurality of anode electrodes 3a to 3e are arranged in parallel in the Y-axis direction, respectively. The grid drive pulse shown in Figure e and the anode drive pulse shown in Figures 3a to 3e are applied. Then, the phosphor at the intersection of the grid electrode to which a positive voltage is applied and the anode electrode to which a positive voltage is applied emits light and becomes a light-emitting dot.

However, as the spacing between the display dots becomes narrower, the width of the grid electrode must also become narrower; however, as the width of the grid electrode becomes narrower, the amount of electrons extracted from the cathode by the grid electrode decreases, and the brightness of the light emitting dot decreases. decreases. Therefore, a one-grid, two-display dot structure in which two anode electrodes are opposed to one grid electrode may be considered, but even in this case, light emission occurs at the end of the grid electrode due to the negative potential of the adjacent grid electrode. In half of the dots, the luminance is low and uneven luminescence occurs. Conventionally, in order to eliminate this uneven light emission, as shown in Figure 4, one grid electrode is opposed to two anode electrodes, and each anode electrode divides one line into four, so-called one grid, two dots, four divisions. A method has been proposed. That is, FIG. 4 is a schematic diagram showing a conventional X-Y matrix fluorescent display tube. To simplify the explanation, a case where the number of displayed dots is 10 is shown, for example. In the figure, 4a to 4d are anode terminals to which the anode drive pulses shown in FIGS. 6a to 6d are input, respectively. Anode electrodes 3a, 3e and 3i are connected to this anode terminal 4a,
Anode electrodes 3b, 3f and 3j are connected to the anode terminal 4b, anode electrodes 3c and 3g are connected to the anode terminal 4c, and the anode terminal 4c is connected to the anode electrodes 3c and 3g.
Anode electrodes 3d and 3h are connected to d.

The grid electrodes 2a to 2e each have a width that is opposite to two display dots, and grid driving pulses shown in FIGS. 5a to 5e are applied to each of the grid electrodes 2a to 2e.

In the X-Y matrix fluorescent display tube with this structure, for example, when the phosphors on the anode electrodes 3d and 3e emit light, the grid electrodes 2b and 2c are connected to the grid electrodes 2b and 2c as shown in FIGS. 5b and 5c. In addition to applying a voltage grid driving pulse, a positive voltage anode driving pulse is applied to the anode terminals 4a and 4d as shown in FIGS. 6a and 6d. Therefore, as shown in FIG. 7, the electrons in the cathode 1 are accelerated and controlled by the grid electrodes 2b and 2c and collide with the anode electrodes 3d and 3e, causing the coated phosphor to emit light and display a luminescent dot. do.

However, for example, an X-Y screen with 256 display dots horizontally (X-axis direction) and 26 display dots vertically (Y-axis direction)
In matrix fluorescent display tubes, the number of grid electrodes is
128, and the number of anode electrodes is 26×4=104.
In addition, there are 256 display dots horizontally (X-axis direction) and 256 display dots vertically (Y-axis direction).
In an X-Y matrix fluorescent display tube having 64 display dots in the axial direction, the number of grid electrodes is 128 and the number of anode electrodes is 64.times.4=256, which increases the number of electrodes. In other words, the number of grid electrodes is horizontal (X
The number of display dots in the vertical direction (Y-axis direction) is 1/2, but the number of anode electrodes is four times the number of display dots in the vertical direction (Y-axis direction). The number of terminals increases in Y matrix fluorescent display tubes.

Therefore, a 1-grid, 1-dot, 2-division formula has been proposed. In other words, FIG. 8 shows the conventional
1 is a schematic configuration diagram showing a -Y matrix fluorescent display tube; FIG. To simplify the explanation, a case where the number of displayed dots is 10 is shown, for example. In the figure, the grid electrodes 2a to 2j are shown in FIGS. 9a to 9j, respectively.
The grid drive pulse shown in is applied. Anode drive pulses shown in FIGS. 10a and 10b are applied to the anode terminals 4a and 4b, respectively. Incidentally, the arrangement relationship between the grid electrode and the anode electrode is shown in FIG.

In the X-Y matrix fluorescent display tube with this structure, for example, when emitting light from the phosphor on the anode electrode 3f, the grid electrodes 2e, 2f, and 2g are connected to the grid electrodes 2e, 9f, and 9f, respectively. A positive voltage grid drive pulse is applied as shown in g. Furthermore, if the timing of the anode drive pulse is selected so that a negative voltage is applied to the anode terminal 4a and a positive voltage is applied to the anode terminal 4b, the anode electrode 3f is selected, and the fluorescent light on this anode electrode 3f is selected. The body lights up and displays luminous dots. In order to display one light emitting dot in this way, it is necessary to select three grid electrodes. In an X-Y matrix fluorescent display tube having this configuration, for example, if there are 128 grid electrodes and 128 anode electrodes, the number of terminals is 128+128.times.2=384. In addition,
In the case of the X-Y matrix fluorescent display tube shown in FIG. 4, the number of terminals is 128.times.1/2+128.times.4=576.

However, in the X-Y matrix fluorescent display tube with this structure, as shown in FIGS. 11 and 12, for example, with the display dots emitting light (grid electrode 2f and anode electrode 3f) at the center,
Since a positive voltage is applied to the left and right grid electrodes 2e and 2g, and a positive voltage is also applied to the anode electrodes 3d and 3h, the electrons emitted from the cathode 1 are transferred to the grid electrodes 2e and 2, respectively.
g, collides with the anode electrodes 3d and 3h, and the phosphor coated thereon emits light with low brightness. In other words, among the anode electrodes located at the boundary between the grid electrode to which a positive voltage is applied and the grid electrode to which a negative voltage is applied, the phosphor of the anode electrode to which a positive voltage is applied emits light. In order to prevent this light-emitting phenomenon, it is necessary to widen the spacing between the display dots, which has resulted in drawbacks such as the inability to arrange the display dots in a high density.

Therefore, an object of the present invention is to provide an X-Y matrix fluorescent display tube in which display dots can be arranged at high density without increasing the number of terminals, and in addition, there is no leakage of light. .

To achieve this objective, the present invention sequentially applies positive voltage grid drive pulses to two adjacent grid electrodes, while each anode electrode is disposed half a pitch offset from each grid electrode, and an even numbered grid drive pulse is applied to two adjacent grid electrodes. The anode electrodes and the odd-numbered anode electrodes are connected in common, and positive voltage anode driving pulses are applied alternately.This will be described in detail below using examples.

FIG. 13 is a schematic diagram showing an embodiment of an X-Y matrix fluorescent display tube according to the present invention. To simplify the explanation, a case will be shown in which, for example, eight display dots are provided. In the figure, 5a to 5h are grid electrodes, and in particular, the grid electrode 5a at the end is formed wider than the other grid electrodes 5b to 5h. 6a to 6h are anode electrodes, respectively, and the positions of the anode electrodes 6a to 6h are as shown in FIG.
It is placed at a position shifted by half a pitch. In other words, the anode electrode is placed at an intermediate position between the grid electrodes.

Note that grid drive pulses shown in FIGS. 15a to 15h are applied to the grid electrodes 5a to 5h, respectively. In addition, anode terminals 4a and 4b
The anode drive pulses shown in FIGS. 16a and 16b are applied to each of FIGS. 16a and 16b.

Next, the operation of the X-Y matrix fluorescent display tube having the above structure will be explained with reference to FIGS. 17a and 17b. First, for example, when displaying light emission from the phosphor on the anode electrode 6e, a positive voltage grid drive pulse shown in FIG. 15d and FIG. The anode drive pulses shown in FIGS. 16a and 16b are applied, respectively. When the anode terminal 4a becomes a positive voltage and the anode terminal 4b becomes a negative voltage, as shown in FIG. 17b, the electrons emitted from the cathode 1 are accelerated and controlled by the grid electrodes 5d and 5e. 6e, its phosphor emits light and displays a luminescent dot. In this case, a positive voltage is applied to the anode electrodes 6c and 6g, but the grid electrodes 5b, 5c, 5f and 5, which are opposite to the anode electrodes 6c and 6g,
Since a negative voltage is applied to both g, electrons do not pass therethrough, and no electrons enter the phosphors on the anode electrodes 6c and 6g, so they do not emit light.

Note that, as shown in FIG. 17a, the dot display operation at the end grid electrode 5a and anode electrode 6a operates in the same manner as described above, but the electrode width is changed from the electrode width of the other grid electrodes. Due to the wider configuration, the number of grid electrodes can be reduced by one. Moreover, although the above description has been made regarding the operation of causing the phosphor on the anode electrode 6e to emit light, it goes without saying that the same operation can be performed when causing the phosphor on other anode electrodes to emit light. In addition, although the above explanation is based on the case where 8 display dots are provided, 9 or more display dots or X-Y
Of course, the same effect can be achieved by arranging them in a matrix.

As explained in detail above, the X-
The Y-matrix fluorescent display tube has the effect of preventing any leakage of light even if the number of anode terminals is minimized.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram showing a conventional X-Y matrix fluorescent display tube, FIGS. 2a to 2e are time charts showing grid driving pulses applied to each grid electrode in FIG. Figures a to 3e are time charts showing the anode driving pulses applied to each anode electrode in Figure 1, and Figure 4 is a time chart of the conventional X-
A schematic configuration diagram showing a Y matrix fluorescent display tube, FIGS. 5a to 5e are time charts showing grid driving pulses applied to each grid electrode in FIG. 4, and FIGS. 6a to 6d are Fig. 4 is a time chart showing the anode drive pulses applied to each anode electrode, Fig. 7 is a diagram for explaining the operation of Fig. 4, and Fig. 8 shows a conventional X-Y matrix fluorescent display tube. Schematic configuration diagram, Figures 9a to 9j are the 8th
Time charts showing grid drive pulses applied to each grid electrode in Figures 10a and 1.
Figure 0b is a time chart showing the anode driving pulses applied to each anode electrode in Figure 8, Figure 11 is a diagram for explaining the operation of Figure 8, and Figure 12 is a diagram showing the grid electrode and anode in Figure 8. A plan view showing the positional relationship with the electrode, FIG. 13 is an X-Y diagram according to the present invention.
FIG. 14 is a schematic configuration diagram showing an embodiment of a matrix fluorescent display tube; FIG. 14 is a plan view showing the positional relationship between the grid electrode and anode electrode in FIG. 13; FIG. 15a
〜FIG. 15h is a time chart showing grid driving pulses applied to each grid electrode in FIG. 13;
16a and 16b are time charts showing anode driving pulses applied to each anode electrode in FIG. 13, and FIGS. 17a and 17b are diagrams for explaining the operation of FIG. 13, respectively. It is. 1... Cathode, 2a to 2i... Grid electrode, 3a to 3j... Anode electrode, 4a and 4
b... Anode terminal, 5a to 5h... Grid electrode, 6a to 6h... Anode electrode.

Claims (1)

[Scope of Claims] 1 N anode electrodes coated with a phosphor and arranged in at least one row (or one column) in the X-axis direction (or Y-axis direction), and N anode electrodes coated with a phosphor and arranged in at least one row (or one column) in the X-axis direction (or Y-axis direction); An X-ray grid that includes N grid electrodes arranged in the direction (or the X-axis direction) and a cathode that emits electrons, and displays at least N light-emitting dots.
- In a Y-matrix fluorescent display tube, positive voltage grid drive pulses are sequentially applied to two adjacent grid electrodes, while each anode electrode is arranged half a pitch offset from each grid electrode, and the even-numbered anode electrode and odd-numbered anode electrodes are connected in common, and positive voltage anode driving pulses are alternately applied to the X-Y matrix fluorescent display tube. 2. The X-Y matrix fluorescent display tube according to claim 1, wherein the width of the grid electrodes at both ends is wider than the width of the other grid electrodes.