JPH03285237A - Gas discharge type display unit - Google Patents

Abstract

PURPOSE:To prevent a deterioration in fluorescent material and realize a high brightness and a high efficiency by installing the fluorescent material close to a cathode at an interval from it. CONSTITUTION:A cathode 5, an anode 6k, and fluorescent material 7 are disposed in a space between flat plates 1, 2 partitioned by partition walls 3 to form a gas discharge display unit. The fluorescent material 7 is disposed close to the cathode 5 at a small interval 8 form it. Deterioration in the fluorescent material 7 by ion impact is prevented by this interval 8. A strong ultraviolet ray generated from negative glow 9 generated close to the cathode 5 is less likely to be absorbed by enclosed gas. but is applied to the fluorescent material 7 to excte it without being shielded by the partition walls 3. Light emission of a high brightness and a high efficiency can thus be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a gas discharge type display device used in a flat display device or a flat illumination device that utilizes a discharge/light emission phenomenon.

BACKGROUND OF THE INVENTION In recent years, thin and portable flat panel display devices have been put into practical use, and their range of application has been greatly expanded, centering on terminal devices for information equipment. In the future, as the amount of displayed information increases due to colorization, it will not only be possible to apply it to terminal devices of information equipment (it will also be possible to apply it to home television receivers, and in the future,
Wall-mounted television receivers can also be realized.

Gas discharge type display devices are colored by exciting the phosphor with ultraviolet rays generated by discharge, producing red and green.

The mainstream method is to obtain the three primary colors of blue, and for example, a configuration as disclosed in Japanese Patent Application Laid-Open No. 112567/1984 is common. A conventional gas discharge type display device will be explained below.

As shown in FIGS. 3 and 4, a discharge space 4 is formed by a back glass substrate 1 and a front glass substrate 2 supported by a partition wall 3. The cathode 5 is placed on the back glass substrate 1, and the anode 6 is placed on the back glass substrate 1.
are formed on the front glass substrate 2 by arranging them in a matrix. In order to prevent deterioration due to ion bombardment, the phosphor 7 is not placed on the cathode 5 where ions are concentrated, but is placed on the anode 6 on the opposite surface. The anode 6 is a transparent electrode in order to extract light emitted from the phosphor 7.

The operation of the gas discharge type display device configured as described above will be described below.

The phosphor 7 is excited by the ultraviolet rays generated by the discharge,
Emit a color unique to phosphors. By applying a voltage to one cathode 5 and one anode 6 arranged in a matrix, discharge and light emission occur in a limited space where they intersect, and one point on the display surface lights up. Information can be displayed in color by lighting up arbitrary points according to the displayed information. If voltage is applied to all the cathodes 5 and anodes 6, the entire surface is illuminated and can be used as a flat lighting device.

As shown in FIG. 5, cold cathode discharge generally produces a negative glow 9. A Crookes dark area 10 and an anode column 11 are formed. The negative glow 9 is formed near the surface of the cathode and emits much stronger light than the positive column 11. Moreover, in the case of a flat display device where the discharge length is short, the positive column 11 is almost non-existent. Instead, the light emitted from the negative glow 9 greatly contributes to the display.

Problems to be Solved by the Invention However, in the conventional configuration described above, before the ultraviolet rays from the negative glow generated very close to the surface of the cathode excite the phosphor on the anode, absorption by the filled gas and light shielding by the diaphragm are necessary. As a result, the excitation efficiency of the phosphor decreases, resulting in a low luminous efficiency and a problem in that sufficiently bright color display cannot be achieved.

The present invention solves the above-mentioned conventional problems, and aims to provide a gas discharge type display device that prevents deterioration of the phosphor and is capable of high-luminance, high-efficiency color display.

Means for Solving the Problems In order to achieve this object, the gas discharge type display device of the present invention comprises two flat plates facing in parallel, a plurality of anodes installed close to one of the flat plates, and a fluorescent A cathode is provided near the other flat plate provided with the body and perpendicular to the anode, and a gap is provided between the cathode and the phosphor.

Effect This configuration makes it possible to install the phosphor near the cathode, avoiding deterioration of the phosphor due to ion bombardment, and preventing strong ultraviolet rays from the negative glow generated near the cathode from being absorbed by the filled gas and by the partition wall. Fluorophores are excited without being blocked by light.

EXAMPLE Hereinafter, an example of the present invention will be described with reference to the drawings.

As shown in FIGS. 1 and 2, a rear glass substrate 1 and a front glass substrate 2 are supported in parallel and opposed to each other by partition walls 3. A cathode 5 is formed in the partition wall 3 in parallel with the front glass substrate 2 by forming a gap 8 between it and the front glass substrate 2 with a distance e corresponding to the thickness of the negative glow determined by the pressure of the filled gas and the discharge current. It is provided. A phosphor 7 is provided on the front glass substrate 2 facing the anode 6 which is arranged in a matrix with the cathode 5 and formed on the rear glass substrate 1. The inter-electrode distance m between the anode 6 and the cathode 5 is set so as to provide the minimum discharge starting voltage based on Paschen's law, which is determined as a function of the product of the inter-electrode distance and the pressure of the filled gas.

Discharge occurs between the cathode 5 and the anode 6, but if a sufficient discharge current flows, the negative glow will spread around the entire surface of the cathode 5, so the ultraviolet light emitted from the negative glow will be absorbed by the filled gas or blocked by the partition wall 3. etc., and directly contributes to the excitation of the phosphor 7. Furthermore, since a gap is provided between the cathode 5 and the phosphor 7, ions flowing into the cathode 5 do not collide with the phosphor 7. The performance of an embodiment of the present invention is compared with a conventional product and is shown in the table below.

As described above, according to this embodiment, deterioration of the phosphor due to ion bombardment can be prevented, ultraviolet rays for excitation of the phosphor can be effectively used, and luminous efficiency and luminance can be improved.

Although a linear cathode is used in one embodiment of the present invention, it goes without saying that a cathode of any shape (for example, a flat plate) may be used as long as a gap is provided near the cathode and the phosphor is placed. stomach.

Effects of the Invention The present invention has a structure in which a gap is provided between the cathode and the phosphor, and the phosphor is provided on the substrate on the cathode side, thereby realizing an excellent gas discharge type display device that can display images with high brightness and high efficiency. It is something.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing a main part of the structure of a gas discharge type display device according to an embodiment of the present invention, and FIG. 2 is a partially cutaway perspective view of the main part. FIG. 3 is a sectional view showing the main part of the structure of a conventional gas discharge type display device, and FIG. 4 is a partially cutaway perspective view of the main part. FIG. 5 is a diagram showing a discharge form formed in a discharge space in gas discharge. 1.2... Substrate, 3... Partition wall, 4...
...Discharge space, 5...Cathode, 6...
- Anode, 7...phosphor, 8... gap.

Claims (1)

[Claims] Two substrates facing each other in parallel, a plurality of anodes installed close to one substrate, and a plurality of cathodes installed close to the other flat plate provided with a phosphor and perpendicular to the anodes, A gas discharge type display device, wherein a gap is provided between the cathode and the phosphor.