JPH02216742A - Fluorescent character display tube - Google Patents

Abstract

PURPOSE:To make it possible to prevent a halation and to obtain a clear display by including a metal oxide with a specific particle diameter in a lead borosilicate type low melting point glass, and limiting the scope of spectroscopic reflectance. CONSTITUTION:On a glass base 1 and a silver wiring conductor 2, a white insulating layer 4 mainly of a lead borosilicate glass powder, including 12% of rutile type TiO2 with the mean particle diameter 3mum and the maximum particle diameter 10mum is formed at the thickness 20mum. On the insulating layer 4, anodes 5 and phosphor layers 6 are formed to obtain an anode base. As a result, the spectroscopic reflectance is made 5-25% in the visible wavelength area, a halation at the surface of the insulating layer is prevented, and a fluorescent character display tube of a good display quality is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a fluorescent display tube, and more particularly to a fluorescent display tube provided with an insulating layer.

[Conventional technology]

Conventionally, the insulating layer of this type of fluorescent display tube generally contains at least one kind of metal oxide as a pigment component.For example, in the case of a white insulating layer, it contains TiO□ as a pigment component. However, as shown in FIG. 3, a white insulating layer 4 having the same color as the ZnO:Zn phosphor layer 6 was formed. This white insulating layer 4 contains TiO□ with an average particle size of 0.5 μm in order to prevent deterioration of display visibility due to entry of external light from the back surface of the anode substrate and to prevent leakage of emitted light to the outside.

[Problem to be solved by the invention]

Although the conventional insulating layer described above has good light-shielding properties during light-emitting display, it causes halation due to light scattering on the surface of the insulating layer.
There was a drawback that a clear display could not be obtained.

An object of the present invention is to provide a fluorescent display tube that prevents halation and provides clear display.

[Means to solve the problem]

The present invention provides a wiring conductor disposed on an insulating substrate, an insulating layer provided with a through hole on the wiring conductor, an anode conductor connected to the wiring conductor via the through hole,
A glass paste forming the insulating layer in a fluorescent display tube that performs luminescent display by electrons emitted from an electrode placed on an anode substrate having a phosphor layer on the anode conductor and spaced from the phosphor layer. contains a metal oxide having an average particle size in the range of 1 to 3 μm as a pigment component to lead borosilicate-based low melting glass, and the spectral reflectance of the insulating layer is 5 to 5 in the visible wavelength range of 400 to 700 nm. It is in the range of 25%.

〔Example〕

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a longitudinal sectional view of a first embodiment of the invention.

First, as shown in FIG. 1, a silver wiring conductor 2 is formed on a glass substrate 1 made of soda lime glass, and a lead borosilicate glass powder with an average particle size of 3.0 μm and a maximum particle size of 10 μm is formed. A white insulating layer 4 with a thickness of 20 μm mainly composed of a certain rutile type TiO2 is formed.
2), an anode electrode 5 was formed using graphite paste on the white insulating layer 4, and a ZnO:Zn phosphor layer 6 was further formed on the anode electrode 5. Using the anode substrate thus obtained, a fluorescent display tube was manufactured by a well-known method.

FIG. 4 is a characteristic diagram showing the relationship between the luminance of the phosphor layer and the luminance of the surface of the white insulating layer due to halation when the phosphor emits light;
FIG. 5 is a characteristic diagram showing the reflectance of each wavelength by the spectroscopic needle.

In order to quantitatively evaluate the display quality of this fluorescent display tube, a bright meter (manufactured by Tokyo 0PTICAL) was used to evaluate the luminance of the phosphor layer and the luminance of the insulating layer surface due to halation when the phosphor emits light. The measurement was carried out and the results are shown in FIG.

As shown in FIG. 4, compared to the conventional insulating layer, the luminance of the phosphor layer and the insulating layer were significantly lower, and there was no halation in the insulating layer, resulting in improved display quality.

The inventor further investigated various insulating pastes using the same method, such as Sample A with an average particle size of 0.4 μm and Sample B with an average particle size of 40 μm, and found that FIGS. As shown in , the spectral reflectance is 5 to 2.
It has been found that when the average particle size is 5%, that is, the average particle diameter is 1 to 3 μm, halation on the surface of the insulating layer due to light emission from the phosphor layer is improved.

FIG. 2 is a longitudinal sectional view of a second embodiment of the invention.

First, as shown in FIG. 2, a mesh-like pattern of A/wiring/112 and a pitch of 150 μm is formed on a glass substrate 1 by sputtering. Electric f! After forming 10, this person! ! pole 1
A white insulating layer 4 with a thickness of 20 μm is formed using a white insulating paste containing 12% of borosilicate lead glass powder and rutile-type TiO2 having an average particle size of 2.0 μm and a maximum particle size of 10.0 μm in the portion excluding 0. did.

On the other hand, a ZnO:Zn phosphor was made into a paste using an organic binder and applied onto the ke electrode 10 to form a phosphor layer 6. Using the anode substrate thus obtained, a fluorescent display tube was fabricated by a well-known method. The display quality of this fluorescent display tube was evaluated using the same method as in the first embodiment, and as shown in FIGS. 4 and 5, halation was significantly improved and the display quality was improved.

〔Effect of the invention〕

As explained above, the present invention is effective in preventing halation caused by light emission from the phosphor layer by setting the spectral reflectance of the insulating layer to 5 to 25% in a fluorescent display tube.

Furthermore, by including a metal oxide having an average particle diameter of 1 to 3 μm, it is possible to obtain a fluorescent display tube with extremely excellent display quality.

[BRIEF DESCRIPTION OF THE DRAWINGS] FIG. 1 is a vertical cross-sectional view of a first embodiment of the present invention, FIG. 2 is a vertical cross-sectional view of a second embodiment of the present invention, and FIG. 3 is a conventional fluorescent display tube. A vertical cross-sectional view of an example, Fig. 4 is a characteristic diagram showing the relationship between the luminance of the phosphor layer and the luminance of the white insulating layer surface due to halation when the phosphor emits light, and Fig. 5 is the reflection for each wavelength by the spectrometer needle. It is a characteristic diagram showing a rate. DESCRIPTION OF SYMBOLS 1...Glass substrate, 2...Wiring conductor, 3...Through hole, 4...Insulating layer, 5...Anode electrode, 6...
- Phosphor layer, 7... Grid, 8... Filament, 9... Cover glass, 10...^e electrode, 12.
...AI! wiring layer. Agent Patent Attorney Susumu Uchihara

Claims (1)

[Claims] A wiring conductor disposed on an insulating substrate, an insulating layer provided with a through hole on the wiring conductor, an anode conductor connected to the wiring conductor via the through hole, and a fluorescent layer on the anode conductor. In a fluorescent display tube that performs luminescent display using electrons emitted from a cathode that is placed on an anode substrate having a body layer with a space between the phosphor layer and the phosphor layer, the glass paste forming the insulating layer is a lead borosilicate-based low-resistance display tube. The melting point glass contains a metal oxide having an average particle size in the range of 1 to 3 μm as a pigment component, and the insulating layer has a spectral reflectance of 400 to 7.
1. A fluorescent display tube characterized in that the wavelength is within a range of 5 to 25% in a visible wavelength range of 00 nm.