JPH037021Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to the structure of a fluorescent display tube that displays numbers, symbols, designs, etc. by emitting light from a fluorescent substance.

Conventionally, this type of display tube has an anode feed line formed of non-transparent Ag wiring on an insulating substrate 1 as shown in Fig. 1, a black insulating layer with through holes provided thereon, and A grid 5 is disposed at an appropriate distance from the anode at a position corresponding to the anode on the anode substrate, which is formed by applying an electrode made of graphite or the like at a position corresponding to the part, and coating a fluorescent material thereon.
In addition, a structure is provided in which a filament is arranged at an appropriate distance from the grit 5, and a cover glass 8 whose inner surface is coated with a transparent conductive film is sealed onto the anode substrate to form a vacuum-tight container. . However, since all of these display tubes are observed from the top surface of a cover glass, they have the disadvantage of poor display field of view.

On the other hand, the insulating substrate is made translucent, the anode electrode group disposed on the insulating substrate is made transparent or a translucent electrode, and a fluorescent material is coated on the anode electrode group, and a fluorescent material is applied on the anode electrode group. The fluorescent display tube is designed to be observed from the side opposite to the electrode-forming side.
The display field of view can be made much better than in the past.

Hereinafter, this structure will be referred to as back emission.

FIG. 2 is a partially enlarged view showing the electrode structure of a conventional back-emitting fluorescent display tube.
A conductive material such as Al is applied on top of the insulating layer 2 by sputtering or the like to form a feeder line and a transparent segment electrode 32 provided by a photoetching method or the like. Cover with

A fluorescent material such as ZnO--Zn is deposited on the upper surface of the transparent segment electrode 32 by electrophoresis or printing to form a fluorescent material 33.

Electrons emitted from the filament cathode 6 are accelerated by the grid electrode 5 and impact the fluorescent material 33, causing the fluorescent material to emit light. The display has a structure in which the image is observed through the light-transmitting segment electrode 32 and the transparent insulating substrate 1. However, recently, with the diversification of display contents, the demand for multi-color display has become stronger. Since the composition of the fluorescent material has to be changed and the fluorescent material application process has to be repeated according to the emitted color, the number of steps has increased compared to conventional single-color products, resulting in lower yields and higher costs.

Furthermore, since the composition of the fluorescent material changes depending on the color of the emitted light, there is a difference in the luminance level of each emitted color pattern, making the display difficult to see.

The present invention aims to reduce the cost and improve the display quality of fluorescent display tubes in these multicolor back-emission display systems.

According to the present invention, a display pattern is formed by forming a fluorescent material on an anode substrate that forms an airtight container, and electrons emitted from the filament are bombarded with the fluorescent material to cause it to emit light. In a fluorescent display tube having a structure in which the display is observed from the surface, a translucent colored film is formed by firing a colored glass paste at a position corresponding to the display pattern on the inner surface of the anode substrate where the display is observed, and the display is colored. By forming the mesh-shaped anode display electrode on the film, it is possible to provide a multicolor display back-emitting fluorescent display tube with low product cost and excellent display quality.

The present invention will be explained in detail below using one embodiment.

Figure 3 is a partially enlarged view showing the electrode structure of the multicolor display back-emitting fluorescent display tube according to the present invention. A colored glass paste made by adding a pigment to a low melting point glass powder as a main component and further adding an organic binder to form a paste was subjected to pattern printing by screen printing and then fired to form a colored film 11 with a thickness of about 10 μm. Next, Al was applied to a thickness of 1 to 1.5 μm by sputtering, and a feed line 4 with a width of 50 to 100 μm and a mesh-like segment electrode 3 with a line width of 20 μm and a pitch of 150 μm were formed by photoetching.
The feed line 4 is formed by depositing a ZnO-Zn fluorescent substance on the top and side surfaces of the mesh segment electrode 32 by electrophoresis, which is covered with the insulating layer 2. A fluorescent material 33 is formed.

From then on, the fluorescent display tube was manufactured using the same process as before.

In this fluorescent display tube, electrons emitted by the filament cathode 6 are accelerated by the grid electrode 5 and impact the fluorescent material layer 33, causing the fluorescent material to emit light. However, the display is similar to the conventional multicolor back-emitting fluorescent display. Due to differences in the composition of fluorescent materials, such as tubes,
The fluorescent display of the present invention provides a multicolor back-emitting fluorescent display tube with improved display quality and high brightness without uneven luminance between display patterns, and in which a transparent colored film is formed on the inner surface of the anode substrate. In the tube, the emitting fluorescent material layer and the colored film 11 are close to each other, so
Compared to the case where a colored film is formed on the outer surface of the anode substrate, the parallax is significantly smaller, and as a result, the display viewing angle can be significantly widened. In addition, since it is formed by firing colored glass paste, it has good adhesion to the substrate, contributing to improved product reliability, and the phosphor is in direct contact with the colored film through the mesh electrode. This not only improves parallax, but also improves brightness. Furthermore, in response to requests for emitted light colors,
There is no need to change the composition of each fluorescent material individually.
We were able to reduce phosphor costs, improve productivity, and significantly reduce product costs.

Although simple embodiments have been described above, it is clear that the present invention is not limited to the color tone and pattern shape of the transparent colored film.

Furthermore, it goes without saying that the material of the electrodes and the method of forming them are not limited to those of the above embodiments.

[Brief explanation of the drawing]

FIG. 1 is a cutaway perspective view of a back-emitting display type fluorescent display tube, FIG. 2 is a partially enlarged view showing the structure of a conventional back-emitting display type fluorescent display tube, and FIG.
1 is a partially enlarged view showing the structure of a back-emission type fluorescent display tube according to the present invention. 1...Transparent insulating substrate, 11...Transparent colored film,
2... Insulating layer, 3... Display pattern, 32... Mesh-shaped segment electrode, 33... Fluorescent material layer,
4... Power supply line, 5... Grid electrode, 6... Filament cathode, 7... Cover glass, 8... External connection lead.

Claims (1)

[Scope of utility model registration request] A display pattern is formed by forming a fluorescent substance on a translucent anode substrate constituting an airtight container, and electrons emitted from the filament are bombarded with the fluorescent substance to cause it to emit light. In a fluorescent display tube where the display is viewed from the opposite side,
A fluorescent display tube characterized in that a translucent colored film formed by baking a colored glass paste is formed on the inner surface of an anode substrate corresponding to a display portion, and a mesh-shaped anode display electrode is formed on the colored film. .