JPS5844658A - Fluorescent display tube - Google Patents

Abstract

PURPOSE:To form a fluorescent electrodeposition screen with good accuracy as well as to miniaturize disposition of anode electrodes by making a shape of phosphor the same as that of a transmittance hole of the anode electrode. CONSTITUTION:In the Figure, 4 denotes anode electrodes having e.g. rectangular transmittance holes 4a while 5 denotes an opaque insulation layer formed around said anode electrodes 4. Further the side of a transparent insulation substrate 2 becomes a visible surface while a grid mesh and a cathode are prepared on the side of the insulation layer 5. In a fluorescent display tube of said constitution a phosphor 3 is electrodeposited from the side of the insulation layer 5, a quantity of possible overfloow is not visible from the side of the insulation substrate 2. Accordingly, so far as seen from the side of the insulation substrate 2, the shape of a display screen of the phosphor 3 is limited to a rectangular transmittance hole 4a so as to enable disposition of the anode electrodes 4 to be miniaturized.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a fluorescent display tube in which the emitting shape of the electrodeposited fluorescent surface can be made constant.〇Figure 1 shows the electrodeposited fluorescent surface of a conventional fluorescent display tube. FIG. In the figure, numeral 1 is an anode electrode formed on an insulating substrate 2 and made of pluquinium, and numeral 3 is a phosphor coated on the anode electrode 1 by electrodeposition.

In the fluorescent display tube having this structure, the phosphor 3 does not adhere to the anode electrode 1 according to its shape, but protrudes beyond the anode electrode 1 as shown in FIG. The amount of protrusion of this phosphor 3 is approximately the phosphor film thickness iur:
◇If this rounding and the arrangement of the anode electrode 1 are made finer, the amount of protrusion of the phosphor 3 cannot be ignored. For example, 30 μm anode electrode 1
When the phosphor 3 is electrodeposited on top, the width of the phosphor 3 is 40 sm.
~80 IIm, which had the disadvantage that the light emitting surface could not be miniaturized.

Therefore, an object of the present invention is to provide a fluorescent display tube whose light emitting surface can be made finer and more uniform.

In order to achieve this purpose, the present invention comprises forming a transparent insulating substrate and a through hole of a desired shape, forming nine anode electrodes on the insulating substrate, and forming an opaque electrode around the anode electrode. The device comprises an insulating layer, a phosphor electrodeposited on an anode electrode from the insulating layer side, a cathode electrode, and a grid mesh, with the insulating substrate side serving as a display surface. This will be explained in detail using .

Figures 3(a) and 3(b) are a front-to-surface plan view and a back-to-back plan view showing an embodiment of the electrodeposited fluorescent surface of a fluorescent surface water tube according to the present invention.

In the figure, 4 is an anode electrode having, for example, a rectangular through hole 4a, and 5 is an opaque insulating layer formed around the anode electrode 40 (see FIG. 4).

Note that the transparent insulating substrate 2N becomes the visible surface, and the insulating layer 5M
is provided with a grid mesh (not shown) and a cathode (not shown).

In a fluorescent display tube with this configuration, the phosphor 3 is covered with an insulating layer 5Ill.
Because it is electrodeposited from the base, even if there is a protruding amount, the insulating group [2
It cannot be seen from Seki. Therefore, as far as viewed from this insulating substrate 21i, the shape of the display surface of the phosphor 3 is limited to a rectangular through hole 4a as shown in FIG. can.

The manufacturing process of the electrodeposited fluorescent surface of the fluorescent display tube having the above structure will be explained with reference to FIGS. 5(a) to 5(c). First, as shown in FIG. 5(a), the anode electrode 4 is placed on the insulating substrate 2. Next, as shown in FIG. 5, an opaque, for example, black insulating layer 5 is applied around the anode electrode 4. Then, as shown in FIG.

Next, as shown in FIG. 6(C), a phosphor 3 is electrodeposited.

Moreover, although the shape of the through hole 4a of the anode electrode 4 is made into a rectangle, it is needless to say that the shape is not limited to this and may be any shape.

As explained in detail above, according to the fluorescent display tube according to the present invention, the shape of the phosphor is K according to the shape of the through hole of the anode electrode.
Therefore, it is possible to form a fluorescent electrodeposition surface with very high precision, and the arrangement of the anode electrode can be miniaturized.

[Brief explanation of drawings]

Figure 1 is a plan view showing the electrodeposited fluorescent surface of a conventional fluorescent display tube;
FIG. 2 is a cross-sectional view taken at A- in FIG. Sekihira map and back side plan, No. 4
The figure is a B-B' sectional view of Figure 3 (a), and Figure 5 (a) ~
FIG. 5(C) is a sectional view showing the manufacturing process of the electrodeposited fluorescent surface of the fluorescent display tube shown in FIGS. 3(1) and 3(b). 1...Anode electrode, 2...Insulating substrate, 3...
...Fluorescent material, 4φ...Anode electrode, 5...φ・Insulating layer. Special pestle applicant: Ise Electronics Industry Co., Ltd. Representative: Masaki Yamakawa (and one other person) Figure 5 4 295-

Claims (1)

[Claims] A transparent insulating substrate and a through hole of a desired shape are formed, and an anode electrode is formed on this insulating substrate, an opaque insulating layer is formed around the anode electrode, and an anode electrode is formed from the insulating layer side. A fluorescent display tube comprising a phosphor electrodeposited thereon, a cathode electrode, and a grid mesh, the display surface being on the insulating substrate side.