JPH07153433A - Electric discharge display element - Google Patents

Abstract

PURPOSE:To provide an electric discharge display element of a low electric discharge starting voltage with little heat radiation at low electric power consumption by disposing a means for reflecting infrared radiation on a glass bulb, and constituting the reflection means of a conductor. CONSTITUTION:A reflection film 20 formed by depositing, e.g. aluminum is disposed on the outer wall of a glass bulb 4. Infrared radiation radiated from a common cathode 2 disposed at the center of the bulb passes through the wall of the glass bulb 4, to be reflected on the reflection film 20. The infrared radiation is radiated approximately in the direction of the common cathode 2 by the reflection film 20, thus re-heating the common cathode 2. With this function, electric power consumption of the common cathode 2 can be reduced. The reflection film 20 by aluminum deposition is a conductor, which functions as an outside proximate conductor, thereby decreasing an electric discharge starting voltage.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a discharge display element such as a fluorescent lamp for display used in a large screen color display device for displaying images and information.

[0002]

2. Description of the Related Art Conventionally, a display device of this type is shown in FIG.
A large number of the discharge display elements 1 shown in FIG. 3 are arranged vertically and horizontally and are incorporated. By appropriately controlling the blinking of the large number of discharge display elements 1, necessary information such as characters and figures is displayed. . FIG. 2B shows the XX ′ cross section of FIG.

The discharge display element 1 is a single tube that emits monochromatic or polychromatic light. In FIG. 2A and FIG. 2B, a common cathode 2 and an auxiliary anode 3 are mounted on a cylindrical glass bulb 4. , A rectangular discharge tube body 5 forming a light emitting chamber is airtightly sealed and combined using, for example, low melting point glass, and the discharge tube body 5 has four light emitting chambers 6a, 6b, 6c,
It is divided into 6d. At the other end of the discharge tube body 5, a face plate 10 made of soda glass, which constitutes a display surface, is also hermetically sealed and combined with a low melting point glass or the like.

The light emitting chambers 6a to 6d have discharge paths formed in a direction parallel to the glass bulb 4, that is, in a direction orthogonal to the face plate 10, and the cross section of the discharge path is tapered so as to open toward the face plate 10. Has become.

Discharge holes 8a, 8b, 8c and 8d, which serve as discharge paths for the common cathode 2, are formed at the bottom of each of the light emitting chambers of the discharge tube 5, and each of the light emitting chambers 6a, 6b, 6c and 6d is formed. On the inner wall surface, for example, the light emitting chambers 6a and 6c are green, 6b
Is coated with red, and 6d is coated with a phosphor 9 that emits blue. The common cathode 2 and the anodes 7a, 7 for selectively discharging the common cathode 2 are provided at the ends of the light emitting chambers 6a, 6b, 6c, 6d, respectively.
b, 7c and 7d are provided.

The discharge display element 1 is filled with argon as a starting gas and mercury, and the phosphor 9 is excited and emitted by ultraviolet rays of mercury generated by the discharge to perform display. Light emitting chamber 6
The light emitted by a, 6b, 6c and 6d is transmitted through the face plate 10 forming the display surface and radiated to the outside to obtain a full color image or information.

[0007]

In a large-screen color display device, for example, about 100,000 discharge display elements 1 are combined to form a screen. Therefore, in order to reduce the overall power consumption, each discharge display element can be reduced. It is necessary to minimize power consumption. Further, in order to ensure reliability and reduce the cost of the entire device, it is necessary to make the discharge starting voltage of each discharge display element as low as possible.

However, in the conventional discharge display element, the infrared radiation emitted from the common cathode 2 which is electrically heated is the glass bulb 4.
Since it is transmitted to the outside and is emitted to the outside, it is necessary to supply a certain amount of electric power to the common cathode 2 in order to keep the common cathode 2 at a predetermined temperature. Does not directly contribute to increase power consumption. In addition, negative glow is generated on the front surface of the common cathode 2 by the discharge, and infrared light is also emitted from this negative glow. Infrared radiation emitted through the glass bulb 4 raises the problem of raising the temperature of the entire large screen color display device. Further, the discharge starting voltage becomes lower as the distance between the display anode 7 and the common cathode 2 becomes shorter, but it is necessary to secure this distance to some extent or more in order to secure a constant luminous efficiency, and the discharge starting voltage becomes high. There is a problem of becoming.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a discharge display element that reduces the power consumed by the common cathode, suppresses the temperature rise of the entire display device, and has a low starting voltage.

[0010]

In order to achieve the above object, in the present invention, a glass bulb 4 accommodating a common cathode 2 is provided.
Means are provided for reflecting infrared radiation over part or all of the inner or outer wall of the and the common cathode 2 is reheated with the reflected infrared radiation. Further, in order to reduce the starting voltage, the means for reflecting infrared rays is made of a conductive material.

[0011]

According to the present invention, the infrared radiation radiated from the common cathode 2 and the negative glow and reaching the glass bulb 4 is reflected toward the inside of the glass bulb 4, so that the infrared radiation is not emitted to the outside, and the display device. It is possible to suppress the temperature rise. Moreover, since the common cathode 2 is reheated by the reflected infrared radiation, the power supply to the common cathode 2 required for keeping the common cathode at a predetermined temperature is small,
Power consumption can be reduced.

Further, by forming the infrared radiation reflecting means with a conductive material, this acts as an outer conductor,
The discharge starting voltage can be lowered.

[0013]

FIG. 1 shows an embodiment of the present invention. In FIG. 1, the outer wall of the glass bulb 4 is provided with a reflective film 20 formed by depositing aluminum, for example. Infrared radiation emitted from the common cathode 2 provided at the center of the bulb passes through the wall of the glass bulb 4 and is reflected by the reflective film 20. The glass bulb 4 is generally cylindrical and the infrared radiation is reflected by the reflective film 20 generally in the direction of the common cathode 2 to reheat the common cathode 2. This action can reduce the power consumption of the common cathode 2.

Further, the reflective film 20 formed by vapor deposition of aluminum.
Is a conductor, which acts as an external proximity conductor and reduces the discharge firing voltage. In addition, in the embodiment of FIG. 1, an insulating coating 21 may be formed on the outer side of the reflective film 20,
As a result, it is possible to protect the reflective film 20 and ensure the durability, as well as obtaining the above effects.

FIG. 3 shows a second embodiment of the present invention. Figure 3
In FIG. 3, the conductive reflective film 20 formed on the outer wall of the glass bulb 4 has the number of display anodes, for example, four in the outer peripheral direction of the glass bulb 4, as shown in FIG. And each of them constitutes a part of the lead wire 22 for supplying a voltage to the display anode. This makes it possible to reduce irregularities on the surface of the glass bulb 4, improve air permeability, and facilitate mounting. In the embodiment of FIG. 3 as well, by forming an insulating film 21 made of, for example, silicon dioxide on the outside of the reflective film 20, the reflective film 20 can be protected and the insulation between the discharge anode lead wires can be secured. It is possible.

FIG. 4 shows a third embodiment of the present invention. Figure 4
In the above, on the outer wall of the glass bulb 4, for example, a multilayer film 23 is formed by alternately laminating two kinds of translucent thin films having different refractive indexes such as titanium dioxide and silicon dioxide. Such a multilayer film has a property of selectively reflecting radiation in a specific wavelength band due to an interference effect of light. By controlling the number of layers of the multilayer film 23 and the thickness of each layer so as to selectively reflect the infrared radiation, the infrared radiation emitted from the common cathode 2 can be reflected and the common cathode 2 can be reheated. As a result, the power consumption can be reduced and the temperature rise of the display device can be suppressed.

[0017]

According to the present invention, by providing the glass bulb with means for reflecting infrared radiation, the heat radiation emitted to the outside can be suppressed and the temperature rise of the display device can be minimized.
Moreover, the common cathode can be reheated to reduce power consumption. Further, by making the infrared radiation reflecting means conductive, it can act as an external proximity conductor to reduce the discharge starting voltage.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of a discharge display device according to the present invention.

FIG. 2 is a sectional view showing a conventional discharge display element.

FIG. 3 is a sectional view showing a second embodiment of the discharge display element according to the present invention.

FIG. 4 is a sectional view showing a third embodiment of the discharge display element according to the present invention.

[Explanation of symbols]

1 ... Discharge display element, 2 ... Common cathode, 3 ... Auxiliary anode, 4 ...
Glass bulb, 5 ... Discharge tube body, 6 ... Light emitting chamber, 7 ... Display anode, 8 ... Discharge hole, 9 ... Phosphor, 10 ... Translucent face plate, 2
0 ... Reflective film, 21 ... Insulating film.

Claims (6)

[Claims] 1. A discharge tube body having a light-transmitting face plate forming a display surface, and a plurality of discharge paths formed in the discharge tube body in a direction intersecting with the face plate. The phosphor is applied to the inner wall surface forming each of the above, each of the discharge paths is provided with an independent electrode at one end on the face plate side, each of the other ends is provided with an independent discharge hole, and is provided so as to face each of the discharge holes. In a discharge display element in which a vacuum container covering a common cathode is provided outside each of the discharge holes, and discharge is made between the electrode and the common cathode, infrared radiation is reflected on the inner surface or the outer surface of the vacuum container. A discharge display element, characterized in that it is provided with means for performing. 2. The discharge display element according to claim 1, wherein the means for reflecting the infrared radiation comprises a metal film formed on the outer wall of the transparent vacuum container. 3. The discharge display element according to claim 2, wherein an insulating film is formed on the outside of the metal film. 4. The metal film formed on the outer wall of the translucent vacuum container according to claim 2, wherein the metal film is divided into two or more pieces in the outer peripheral direction of the vacuum container to apply a voltage to the face plate side electrode. A discharge display element forming a part of a conductive means. 5. The discharge display element according to claim 4, wherein an insulating film is formed on the outside of the metal film. 6. The discharge display element according to claim 1, wherein the means for reflecting infrared radiation comprises a multilayer film formed by laminating two or more kinds of translucent thin films having different refractive indexes on the inner wall or the outer wall of the vacuum container. .