JPS5814520Y2 - fluorescent display tube - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a fluorescent display tube, and particularly to a fluorescent display tube that can be identified even under high illumination.

Generally, a fluorescent display tube has a wiring conductor 2 deposited on a substrate 1, as shown in FIG. An insulating layer 3 is laminated to provide electrical insulation.

This insulating layer 3 is provided with a through hole 3a at a predetermined position, and the wiring conductor 2 and the anode conductor 4 are electrically connected through the through hole 3a by a conductive material, and the anode conductor A phosphor layer 5 is deposited on 4 to form an anode 6.

Further, the anodes 6 are arranged in a Japanese character shape to form a -digit pattern display section 7.

Further, a control electrode 8 having a fine mesh that does not interfere with the observation of light emission from the anode 6 is disposed above the anode 6, and a control electrode 8 that is heated and has a mesh shape that does not interfere with observation of the light emission from the anode 6 is provided above the anode 6. A filament-shaped cathode 9 that emits ions is stretched, and a front envelope 10 that constitutes a vacuum envelope together with the substrate 1 is sealed around the periphery of the substrate 1, and each of the electrodes is maintained in a high vacuum atmosphere. In addition, an introduction terminal 11 is provided which hermetically penetrates the sealed portion between the substrate 1 and the front enclosure 10 and is electrically connected to each of the electrodes.

Thus, the cathode 9 is electrically heated, and the desired control electrode 8 is heated.
By applying a predetermined potential to the anode 6, the anode 6 is excited by the bombardment of electrons and emits light, thereby providing a display.

By the way, this fluorescent display tube can be driven at low voltage, consumes little power, and provides a bright and easy-to-read luminescent display, so it has recently become popular as a display device for various electronic and electrical devices. came to be used.

As the field of application of fluorescent display tubes has expanded, the environments in which they are used have also diversified. The environments in which it is used are diverse, ranging from use in extremely bright environments that may be exposed to light.

In this case, when using in a bright environment, outside light
0 to the insulating layer 3 and the phosphor layer 5 of the anode 6,
There is a problem in that the reflected light enters the observer's eyes together with the light from the emitting anode 6, reducing the visibility of the emitting anode 6.

Therefore, various efforts have been made to improve visibility when used in such bright environments.

For one thing, this kind of fluorescent display tube generally has
Noting that the insulating layer 3 is blackened by mixing oxides of metals such as Co, Fe, Mo, and Cr as pigments, the phosphor layer 5 is white or grayish-white, and the above-mentioned A black pigment is added to the phosphor layer 5 to darken the phosphor layer and reduce the reflectance of external light on the anode surface, thereby improving the contrast between the light-emitting anode and the non-light-emitting anode, and improving the contrast between the light-emitting anode and the non-light-emitting anode. There has been an attempt to visually bury it in the insulating layer 3 to improve overall visibility.

However, mixing a non-luminous pigment material into the phosphor layer 5 reduces the luminescence intensity of the phosphor layer 5, and is still not sufficient for improving visibility.

On the other hand, the phosphor layer 5 is left as is, and the insulating layer 3 is
Attempts have also been made to mix pigment materials that have approximately the same color as the phosphor layer 5.

In this case, without reducing the emission intensity of the emitting anode,
An advantage is that the non-emissive anode can be visually buried in the insulating layer.

However, when the insulating layer 3 is whitened to match the phosphor layer 5, when the external light incident on the phosphor display tube is strong, the intensity of the reflected light from the insulating layer 3 increases accordingly, which interferes with observation. cause

Further, as described above, in the fluorescent display tube, a control electrode 8 for accelerating and controlling electrons is provided above the anode 6, and this control electrode 8 is usually made of Fe-N.
An alloy of i-Cr is used, and the surface is oxidized to improve adhesion when fixed to the substrate 1 and front envelope 10 with low melting point frit glass, giving it a greenish-black color.

Furthermore, when the input power is increased to increase the luminance, the flow of electrons flowing into the control electrode 8 also increases and the control electrode 8 generates heat, so in order to improve the heat dissipation,
It is desirable that the control electrode 8 and the frame member supporting the control electrode 8 within the envelope be blackened.

Therefore, if the insulating layer 3 is whitened to match the phosphor layer 5, the black-colored control electrode 8 will be conspicuously observed, which is not desirable in terms of display quality.

In view of the above points, the present invention provides an insulating layer around the anode that has almost the same color as the anode when it is not emitting light, on the substrate around the anode within the range where the control electrode faces. , a darkened insulating layer of approximately the same color as the control electrode is deposited on a portion of the substrate other than the portion where the insulating layer is deposited around the anode, so that it can be used under high illumination. The purpose of this is to prevent the non-luminous anode, control electrode, supporting member thereof, etc. from being conspicuously observed, thereby improving visibility and display quality.

Next, an embodiment of the fluorescent display tube according to the present invention will be described with reference to the drawings.

FIG. 2a is a plan view of a main part showing an embodiment of a fluorescent display tube according to the present invention, and FIG. 2A is a sectional view of a main part of the same embodiment.

Here, 21 is a base material made of an insulating material such as glass, and 22 is a wiring conductor formed on this substrate 21 in a predetermined pattern.

Then, a first insulating layer 23 is laminated on the substrate 21 including the wiring conductor 22 such that a through hole 24 is formed at a predetermined position communicating with the wiring conductor 22.

For example, when the surface of a control electrode (to be described later) has a greenish-black or black color, the first insulating layer 23 is formed in such a way that the first insulating layer 23 exhibits a color that is almost the same as that of the control electrode. The insulating layer 23 includes Fe, Ni, Co, Mn.
By mixing metal oxides such as, it is colored greenish-black or black to darken it.

Furthermore, 25 is a second insulating layer, which is placed on the first insulating layer 23 around the anode, which will be described later, and on the wiring conductor 22 within a range that does not protrude from the frame of the mesh portion of the corresponding control electrode. A through hole 24 is formed at a predetermined position communicating with the laminate.

The second insulating layer 25 is formed by mixing an appropriate pigment so as to have approximately the same color as the phosphor powder forming the phosphor layer deposited on the anode. When the phosphor powder is white or grayish white, a powder of a metal oxide such as T io 2, which is white in powder form, is mixed in to color it so that it has almost the same color as the phosphor layer.

Further, 26 is an anode conductor formed on the second insulating layer 25 in communication with a predetermined wiring conductor 22 via a through hole 24 and in a predetermined pattern, for example, in the shape of a Japanese character as shown in the figure. A phosphor layer 27 is deposited on this anode conductor 26 to form an anode 28.

A control electrode 29 is arranged above and facing this anode 28 at a predetermined interval.

The control electrode 29 includes a mesh portion 29a having an aperture ratio that does not interfere with the light emission of the anode 28, and a frame portion 29b that holds the mesh portion 29a.

The frame portion 29b also includes a support member 31 that supports the control electrode 29 at a predetermined distance from the anode 28 and also serves as a signal introduction terminal from the outside to the control electrode 29.
are formed integrally, and in order to improve adhesion when fixed to the substrate 21 and to improve heat dissipation, an oxide film or the like is formed on the surface thereof, giving it a greenish-black or black color.

Furthermore, one or more filament-shaped cathodes 30 are stretched above the control electrode 29, and a front enclosure (not shown) is sealed around the periphery of the substrate 21 to exhaust the inside. The structure is such that each of the above-mentioned electrodes is held in a high vacuum atmosphere.

That is, in the phosphor display tube according to the present invention, the peripheral area A of the anode 28 is colored almost the same color as the phosphor layer 27, for example, grayish white, as shown in the colored explanatory area surrounded by the black line in FIG. 2a. This allows the non-emissive anode to be visually buried.

Further, since the portion B of the anode 28 excluding the peripheral portion A is approximately the same color as the control electrode 29, for example black, the control electrode 29 is not visible to the observer.

Thus, a desired anode 28 is connected via an introduction terminal (not shown).
When an anode potential is applied to the anode 28, the anode 28 emits light and a display is obtained.

In this case, the non-luminescent anode is buried in the surrounding insulating layer 25 of the same color and is not visible to the observer.
Only the anode 28 that emits light can be observed, improving visibility.

In addition, strong external light may enter the insulating layer 25 and the non-luminous anode 28.
Even if the reflected light from the insulating layer 25 becomes strong, the non-emissive anode 28 will not be visually observed as being lifted from the insulating layer 25, and the anode 28 will emit light even in a bright usage environment.
becomes clearly visible.

Moreover, in this case, the insulating layer 2 is almost the same color as the non-emitting anode.
5 exists only in a limited area around the anode 28, and other areas are darkened, so the area where reflection occurs is extremely small and does not interfere with observation.

On the other hand, the frame portion 29b and the support member 31 of the control electrode 29 are
Since it has almost the same color as the insulating layer 23, it is visually buried in the insulating layer 23, and even when strong external light is incident, the control electrode 29, its frame 29b, or the support member 31 Since there is no noticeable discrimination, an extremely high quality display can be obtained.

Here, the insulating layer in the above embodiment has a structure in which the second insulating layer 25 around the anode is laminated and deposited on the first insulating layer 23 whose color is almost the same as that of the control electrode. However, the present invention is not limited thereto, and the second phosphor layer, which has almost the same color as the phosphor layer in the non-emission state, is provided on the substrate on which the wiring conductor is formed, including at least the area around the anode. Then, a second insulating layer, which becomes approximately the same color as the phosphor layer, is coated with a second insulating layer that has approximately the same color as the control electrode, except for the area around the anode within the area facing the control electrode. For example, a first insulating layer of black color may be deposited, and a first insulating layer of approximately the same color as the phosphor layer may be deposited.
The insulating layer part and the second insulating layer part, which has almost the same color as the control electrode, have a single-layer structure so that no parts are stacked on top of each other, so that pigments mixed between the anode peripheral part and other parts can be removed. You may change it.

Furthermore, although the pattern shape in the above embodiment is a Japanese character shape, it is not limited to a Japanese character shape, but can be arbitrarily formed such as a Japanese character shape or a dot shape.

As explained above, according to the fluorescent display tube according to the present invention, the peripheral part of the anode facing the control electrode is made almost the same color as the non-emitting anode, and the part other than the part around the anode is made almost the same color as the control electrode. As a result, even if strong external light enters the display surface, the non-emitting anode will not be seen floating away from the surrounding area, making it easier to distinguish it from the emitting anode, and improving visibility. An excellent effect of improvement can be obtained.

On the other hand, the other parts except for the anode and its surroundings are darkened, so there is almost no reflection in these parts, which has the excellent feature of providing an extremely easy-to-observe display even under high illumination. have.

In addition, the area of the white part of the insulating layer that reflects external light is within the range of the control electrode, and the area within the range of the control electrode does not reflect external light due to the mesh-like surface of the control electrode. Since the filter is blocked, the color, density, etc. of the filter provided on the front of the front enclosure can be selected as necessary.
For example, when a light-colored filter is used, it has the excellent feature of being able to extract light from the emitting anode without attenuating it, and the control electrode and its supporting members can be clearly observed under high illumination. This provides the excellent effect of providing an extremely easy-to-read, high-quality display without being distorted.

[Brief explanation of the drawing]

Figures 1a and b are a partially cutaway plan view and sectional view showing a conventional fluorescent display tube, Figure 2a is a plan view of essential parts of a fluorescent display tube according to this invention, and Figure 2 is the same FIG. 21...Substrate, 23...First insulating layer, 25...Second insulating layer, 28...Anode, 29... Control electrode, 30... cathode.

Claims (1)

[Scope of utility model registration request] A control electrode is disposed above the pattern display area, which is formed by disposing a plurality of anodes on the top surface of which a phosphor layer is disposed on a substrate, and a filament-shaped cathode is further stretched above the control electrode. In a fluorescent display tube that displays characters and figures by selectively bombarding the anode with electrons emitted from the cathode, the substrate in the vicinity of the anode within a range facing the control electrode. An insulating layer of approximately the same color as when the anode is not emitting light, which is disposed above, and an insulating layer disposed on a portion of the substrate excluding a peripheral portion of the anode within a range facing the control electrode on which this insulating layer is disposed. A fluorescent display tube comprising: a darkened insulating layer having substantially the same color as the control electrode.