JPS6017839A - Display device with fluorescent character display tube - Google Patents

Abstract

PURPOSE:To obtain high resolution and large-sized display by providing both sides of an insulating plate having plural holes arranged in the matrix shape with a line grid electrode group and a column grid electrode group while applying a phosphor uniformly on the anode electrode. CONSTITUTION:Assuming that the grid electrodes GA1 and GB1 attached to both surfaces of an insulating plate 3 are impressed by voltage +B1, thermal electrons from a filament F pass through the holes 1-1 while reaching the anode electrode A. Thereby, said thermal electrons collide with a phosphor L applied on the anode electrode A so that the part directly under the holes 1-1 and in their neighborhood are to radiate. At least either of the upper-and-lower grid electrodes of the holes excepting the holes 1-1, at which the grid electrodes GA1 and GB1 intersect, is pulled down to earth potential so that the grids are reversely biased to the filament F thus making the electrons unable to pass said holes. Accordingly, optional two-dimensional picture display is possible by scanning said grid electrodes by turns.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a fluorescent display device, and more particularly to a fluorescent display device suitable for displaying television images.

The structure of a fluorescent display tube display device that displays two-dimensional images such as television images is shown in FIG. 1, in which (a) is a perspective view, and (b) is a cross-section taken along the line It is a diagram.

Filament F1~ is placed in the gap between the upper and lower glass plates 1 and 2.
F5. It is constructed by combining grids 01 to G6, anodes A1 to A5, and dot-shaped phosphors to L5 as shown.

That is, the strip-shaped anode electrodes A1 to A5 are mounted parallel to each other on the glass plate 2, and the anode electrodes A
Strip-like grid electrodes G and -G7 are arranged so as to be orthogonal to each other, and dot-like phosphors L1-L5 are applied on the anode electrodes at the intersections of these anode electrodes and the grid electrodes, respectively. There is. A plurality of filaments F, -F3 are arranged on these grid electrodes.

FIG. 2 is a diagram showing an equivalent circuit and a drive circuit of the fluorescent display tube shown in FIG. 1. As shown in FIG. A voltage several delts higher than the ground potential is applied by the Zener diode ZD. Each anode electrode A, ~A5 and each grid electrode 01~G5
A positive voltage element B is applied to the drive circuit shown in FIG. 2(b) (both electrodes are shown as five in FIG. 2). In b) only one anode and one grid electrode are shown for simplicity. Each drive transistor Q1゜Q2
A positive voltage element B is applied to each emitter of , and each collector is grounded down by resistors R1 and R2.

An anode control signal or a grid control signal is supplied to the base of each transistor, respectively.

When lighting, electrons generated from the filament F are applied to the corresponding grid and anode (turning on the corresponding drive transistor) so that the phosphor to be lit lights up. The current flows toward the anode and becomes an anode current, causing the phosphor to emit light.

Note that the drive transistor Q1. Each base of Q2 is pulled up by a resistor R3+R+4, and is designed to draw the υ base current by the control o-/l/signal in order to turn on the transistor when the transistor is turned on, and when it is not lit, the control signal input terminal is pulled up. becomes high impedance.

In such a conventional device, in order to make the display dots smaller, it is necessary to make the grid electrode thinner accordingly, and there is a limit in terms of strength to making the grid of the mesh structure finer. Furthermore, when a thin grid is used, the mounting accuracy deteriorates and the grid becomes susceptible to vibration. Furthermore, when placing the phosphor on the anode electrode, it is necessary to apply it accurately in the form of dots, which is difficult to manufacture. Particularly when obtaining a large display panel, the above-mentioned strength problem becomes a serious problem, and obtaining small dots is difficult.

The present invention has been made to eliminate the above-mentioned drawbacks, and its object is to provide a phosphor display tube display device which enables high resolution and large-sized display by reducing the size of melting display dots.

A fluorescent display device according to the present invention includes: an insulating plate having a plurality of holes formed through the thickness direction and arranged in an IJ sock shape; A group of row grid electrodes attached along each row of the matrix, a group of column grid electrodes attached along each column of the matrix on the other main surface of the insulating plate, and a group of column grid electrodes installed facing one main surface of the insulating plate. an anode electrode provided facing the other main surface of the insulating plate; and a phosphor provided over substantially the entire surface of the anode electrode facing the other main surface of the insulating plate. The present invention is characterized in that a control voltage is selectively applied to the row and column grid electrode groups to display a two-dimensional image.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 3 is a diagram showing one embodiment of the present invention, in which (a) is a perspective view, and (b) is a sectional view taken along the Y-Y line in (a).

There are upper and lower glass plates 1 and 2, and an insulating plate 3 is provided between them. This insulating plate 3 has a plurality of holes 1 passing through it in the thickness direction. -1. , ], -2,...
・, 2-1.2-2, ..., 3-1', 3-2
．． ... are bored, and these holes are arranged in a matrix. On one main surface (upper surface) of this insulating plate 3, row grid electrode groups GA are arranged along each row of a matrix formed of a plurality of holes.

Ga4. . . . are attached along each column of the matrix on the other main surface (back surface). GB2. ...song... is installed. A hole is similarly provided in the portion of each grid electrode facing the matching hole of the insulator 3, and the filament F,
The emitted electrons from ~F4 reach the anode electrode A.

This anode electrode A is a transparent electrode formed on the entire upper surface of the glass plate 2, and a phosphor is formed over almost the entire upper surface of the electrode A, that is, the surface facing the back surface of the insulating plate 3. It is coated.

FIG. 4 is a diagram showing the circuit configuration of the drive circuits 4 and 5 of the device shown in FIG. ) is pulled down to ground potential. A positive voltage element B is applied to each row grid electrode group through a corresponding PNP transistor (QA), and a positive voltage element B is applied to each column grid electrode group through a corresponding NPN transistor (QB). It is now possible to do so.

Each pace of the transistor (QA) is connected to a positive voltage element B1 by a resistor (Rc), and a grid control signal is applied thereto. Further, each base of the transistor (QB) is pulled up to a positive voltage terminal B1 by a resistor (RD), and a grid control signal is applied thereto. A positive power source (not shown) B2 is always applied to the anode electrode A, and the filament is driven in the same manner as the conventional example shown in FIG. 2(a).

In this configuration, if voltage element B is selectively applied to, for example, grid electrodes GA1 and GB2 by a grid control signal, thermoelectrons from the filament pass through hole 1-1 and reach anode electrode A. reach At this time, it collides with the fluorescent material coated on the anode electrode A, and the portion directly below the hole 1-1 and its vicinity emit light. Since at least one of the upper and lower grid electrodes of the holes other than hole 1-1 where these grid electrodes GA and GB2 intersect is pulled down to the ground potential,
With the grid reverse biased relative to the filament F, electrons can pass through these holes, so that no phosphor emission occurs below the surface of these holes.

Therefore, by sequentially scanning these grid electrodes, it is possible to display any two-dimensional image. In reality, the display will be visually observed through the glass plate 2 from the back side of the anode electrode A (the side opposite to the filament F).

5 and 6 are perspective views showing a part of another embodiment of the present invention, and parts equivalent to those in FIG. 3 are designated by the same reference numerals. This is a modification of the structure of the grid electrodes attached to the upper and lower surfaces of the insulating plate 3, and FIG. 5 shows a mesh-shaped grid electrode structure. In FIG. 6, the rod-shaped wire electrode structure has a diameter smaller than the diameter of the hole 1-1, etc., and the wire electrode is fixed by fitting the wire into a groove provided in the insulating plate 3. We ensure that

FIG. 7 shows a part of another embodiment of the present invention, which is a modification of the anode electrode and has a structure suitable for displaying television images. That is, the anode electrodes are a pair of comb-shaped structure electrodes A1o and A2°, which are arranged so that the teeth of both electrodes face each other and mesh with each other, and are mounted on a glass plate 2 (see FIG. 3). These comb-shaped electrodes A1o, A2o
The phosphor is coated almost entirely on the glass plate 2, including the upper surface thereof. These comb-shaped anode electrodes A,. ,A2o
The positional relationship between the insulating plate 3 and the matrix-like holes of the insulating plate 3 is as shown in FIG. That is, the matching hole is anode A,
. and A2o, respectively.

The grid electrode structure shown in FIG. 3 and each side of FIGS. 5 and 6 is applied.

FIG. 8 is a diagram showing an example of a drive circuit when a display device to which the anode electrode of FIG. 7 is applied is used for television reception. Both anode electrodes A. , A2o are supplied with a voltage element B2 via a switch SW, and are pulled down to ground potential via resistors R, . . . , RF, respectively.

Incidentally, the respective outputs of the drive circuits 4 and 5 shown in FIG. 4 are applied to the grid electrodes GA and GB.

For even fields of television signals, the anode electrode A,. By applying a positive voltage element B2 to the anode electrode A2o and controlling the switch SW so as to apply a positive voltage to the anode electrode A2o for odd fields, interlacing becomes possible and an image display of a television signal is possible. If interlace is not required, a positive voltage may be applied to both anode electrodes A101A-2G'.

As shown in the figure, according to the present invention, a phosphor is uniformly applied on the anode layer, a small hole is made in the insulating plate, and the phosphor corresponding to the small hole is made to emit light. Therefore, the conventional drawbacks can be solved and a display device with good strength can be obtained.

Furthermore, the resolution is determined by the size of the hole in the insulator, the pinch, etc., and there is no longer the difficulty of spotting the phosphor dots as in the past. The display surface is uniformly coated with phosphor, so
When looking at the display screen, it has the advantage that it looks like a conventional dot matrix.The drive circuit is not limited to the example shown in the figure, and can apply a positive voltage to the grid or anode of the filament. In that case, various circuits can be used. By increasing or decreasing the voltage element B1 applied to the grid or the voltage element B2 applied to the anode voltage, the luminance of light emission can be changed, so that the display can be modulated in brightness, as shown in Figures 7 and 8. Although it can display monochrome TV images,
A third grid for brightness control may be provided between the filament and the insulator.

The cross section of the small hole drilled in the insulating plate is not limited to a circular shape, but can be modified in various ways.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the structure of a conventional fluorescent display device, FIG. 2 is an equivalent circuit diagram and drive circuit diagram of the device in FIG. 1, and FIG. 3 is a diagram showing the structure of an embodiment of the present invention. 4 is a drive circuit diagram of the device shown in FIG. 3, FIGS. 5 to 7 are diagrams showing respective parts of other embodiments of the present invention, and FIG.
FIG. 2 is an equivalent circuit diagram of a device configured using the anode electrode shown in the figure. Explanation of symbols of main parts 3... Insulating plate] -1, 1, -2, 1-3, 1-/1... Holes GA, G
B... Grid electrode A... Anode electrode F... Filament ■,... Fluorescent body 11- 12- Ground 6 Figure Spoon 7 Figure/-17-6

Claims (2)

[Claims] (1) An insulating plate having a plurality of holes perforated in the thickness direction and arranged in a matrix, and row grid electrodes attached along each row of the matrix on one main surface of the insulating plate. a group of column grid electrodes attached along each row of the matrix on the other main surface of the insulating plate, a filament provided facing the J main surface, and a filament arranged opposite the other main surface of the insulating plate. and a phosphor provided over substantially the entire surface of the anode electrode facing the other main surface of the insulating plate, and a control voltage is applied to the group of grid and column grid electrodes. A fluorescent display device that displays a two-dimensional image by selectively applying voltage. (2) The anode electrode is composed of a pair of comb-shaped electrode structures, and the tooth portions of the pair of comb-shaped electrode structures are arranged to face each other, and the voltage applied to the pair of comb-shaped electrode structures is 2. A fluorescent display device according to claim 1, wherein the voltage is alternately switched.