JPS60205494A - Color display unit - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a color display device using a fluorescent display tube.
In particular, the brightness can be adjusted.

[Prior art]

Fig. 1i shows the drive circuit of a conventional fluorescent display tube.
In the fluorescent display tube +1), electrons emitted from the directly heated filament (4) are accelerated by
By colliding with the anode (21), the phosphor coated on the surface of the anode (21) is excited and emits light.
Any desired display can be obtained by controlling the grid (3) with the drive circuits (5), (0) and controls F71, +8). Here, ViJ pole (2
) and grid (3) drive circuits (5) and (6) switch the power supply voltage V+ according to their respective control signals to the wA pole (21 and grid (3) of the fluorescent display tube (]). lead.

At that time, the brightness of the display is the same as that of filament (4),
3) and the voltage between the anode (1) or the duty ratio of the drive waveform. Note that +9) f is a filament composed of a transformer whose midpoint is connected to a reference potential.

However, in the conventional Kakull method, Kaku! The Tll+ voltage is determined by the DC power supply ■+ of the drive circuit, and is usually fixed at a constant voltage. When using multiple fluorescent display tubes side by side, it is difficult to adjust the brightness of each fluorescent display tube, especially for color fluorescent display tube number ζ, to arbitrarily adjust the brightness of each color. There was a drawback.

[Summary of investigation]

This research was carried out in order to eliminate the drawbacks of the conventional ones as described above.
l'ffEE between the power input of one dynamic pole drive circuit and the power supply
It is an object of the present invention to provide a display device using a fluorescent display tube that can easily adjust the brightness of each color and adjust the color tone by providing a 21 adjustment circuit.

[Embodiments of the invention]

Hereinafter, an embodiment of the present invention will be described with reference to FIG. Second
In the figure, Oll is a color fluorescent display tube, with red,
A number of anodes are coated with phosphors that emit light in the eight primary colors of blue (in the figure, R indicates the anodes coated with red, G indicates green, and B indicates the anodes coated with blue phosphors. ), a grid (3), and a directly heated filament (cathode) (shown in the drawing) are housed in a vacuum container. The anodes 1i coated with phosphors of 83 colors are connected in parallel for each color and are not drawn out of the display tube, and each color has a g-movement circuit (5). The drive circuits (5) respectively switch the input signal tζ and hence the power supply input voltage.

It is something that causes a lot of damage. Between the power input of each drive circuit (5) and the common DC power supply Va, a voltage adjustment circuit 0 (l) as shown in FIG. (6) is for each grid (
3) are commonly connected drive circuits, (71 (al) are controls for the anode, grid, and do, respectively, and have the same functions as those shown in FIG. 1.

The voltage adjustment circuit (9) is used to arbitrarily correct variations in display tube drive circuit number ζ setting (plane brightness, etc.), and as shown in FIG.
b) and a resistor (10c), divides the voltage of the direct voltage V+ and supplies a control voltage to the drive circuit side, that is, to the anode (2) and the grid.

In the above configuration, the relationship between the luminance of the fluorescent display tube θ1) and the driving voltage is as shown in FIG. 4.5. Cathode 1 of fluorescent display tube OB! This is a directly heated filament, and in order to prevent the fjJ gradient caused by the voltage drop across the filament from becoming a brightness gradient, the filament source uses alternating current. Therefore, when lighting is not required, the midpoint M of the filament source (9) is set to the cutoff potential EK so that the anode (2) or grid (3) is negative ζζ with respect to the filament midpoint number ζ. Ru. Therefore, the drive fltll voltage ebC that determines the brightness of the fluorescent display tube 01) is as shown in FIG.

The driving circuits (5) and (6) of the fluorescent display tube OB are for switching the input voltage VD to the display tube from the signals from the controls (7) and (8).
If D is made variable, the drive voltage ebc becomes variable, and the fourth
The brightness can be adjusted according to the number of times.

In the embodiment, each voltage adjustment circuit 01j li is intended to easily realize the 10r effect, and the DC voltage regulator is divided into two parts, and the output VD is connected to I through a transistor (10a).

By changing the partial pressure ratio of the lever, the brightness of the display tube can be easily adjusted. in this way? < +OJ+ By variable control of the l'ff pressure value, variations in the brightness of the display tube can be easily corrected.

The color temperature of a color display installed is determined by the chromaticity and brightness ratio of the three primary colors R, G, and B, and by adjusting this brightness ratio, the color temperature can be set and the color tone can be adjusted.

In the above embodiment, a plurality of grids (3) are provided in the fluorescent display tube 01), but each grid, grid (3)
The present invention may be constructed by arranging a plurality of fluorescent display tubes for each type 17, and the present invention is also effective for a fluorescent display tube 0υ1ζ provided with a common grid (3) as shown in FIG.

When using multiple display tubes side by side, use +r like this
By variably controlling the M#JN pressure value, variations in brightness of individual display tubes can be easily corrected.

〔Effect of the invention〕

As described above, according to the present invention, the anode of the fluorescent display tube is wired for each color, and a drive circuit is provided for each color.
By adjusting the H dynamic Fα pressure, it is possible to adjust the brightness for each color, making it easy to set the color temperature or adjust the tint.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram showing a conventional drive circuit for a fluorescent display tube, FIG. 2 is a circuit diagram showing an embodiment of the present invention, and FIG. 8 is an example of the adjustment circuit in FIG. 2. The circuit diagram shown in Figure 4 is a characteristic diagram showing the relationship between drive voltage and brightness, and Figure 5 is a characteristic diagram showing the relationship between drive 7 voltage and brightness.
A waveform diagram showing the relationship between l'ru pressure, filament m position, and cutoff voltage, and FIG. 6 is a circuit diagram showing another implementation of the present invention. 12+ - GRID IM, (3)・grid, (4)・・filament, (5), (6)・・drive, 11+ circuit, 00・・
・)d pressure adjustment circuit, OD...color fluorescent display tube, v+,
Va,,, direct M w s I' [f sweat, Vp '' voltage, output cuff H pressure, N1 midpoint of filament power supply, ef・filament voltage, 1mm 1・force, to-off voltage, ebc・・Grid and ■ 1) Voltage, ■
...lfl pole drive DC pole, v2 Grid 4. Dokuri rM
For rl! Flow source, RlG, B-・So] The red, green, and blue phosphors are placed in the main area. '+1- sign indicates the same or equivalent part. Agent Masuo Oiwa Figure 1 Figure 3 Figure 0 Figure 2 Figure 4 fbC Figure 5

Claims (1)

[Claims] (1) A fluorescent display tube having an anode coated with phosphors that emit light of the three primary colors, a cathode that emits electrons, and a grid that controls the flow of the electrons, one for each of the three primary colors. (1) A drive circuit for supplying a drive voltage to the anode of the fluorescent display tube, and a drive circuit for each color provided between the drive circuit and the drive power source. I control the voltage! A color display device equipped with a sweat adjustment circuit.