JPS5815898B2 - fluorescent display tube - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is applicable to displays of letters, numbers, various figures, etc. (hereinafter referred to as letters, etc.) in places where the ambient brightness changes frequently, such as luminescent displays of various in-vehicle instruments and time, etc. This invention relates to a fluorescent display tube suitable for.

The phosphors used in fluorescent display tubes are usually pure white powders.

In addition, ZnO:Zn phosphors are often used because they provide an extremely bright and easy-to-see luminescent display using a low-speed electron beam, and the luminescent color is a bright greenish color.

Therefore, when used in bright daylight, the non-luminescent portions of the segment anode covered with the phosphor also become extremely bright white, making it easy to distinguish between the luminescent display portion and the non-luminescent portion. The problem was that it was extremely difficult.

In response to this, various proposals have been made to solve the above-mentioned problems.

One of the proposals is to make the color around the segment anode part that emits light white or black-gray.

However, in both cases, there is no difference in the color of the luminescent and non-luminescent parts of the phosphor portion of the segment anode, so for luminescent display in extremely bright places, the difference between the luminescent and non-luminescent parts of the segment anode is There was a problem in that it became difficult to distinguish between the two, making it difficult to obtain a sufficient discrimination effect.

As another example, various proposals have been made to color the entire white phosphor in a color other than white by coating or mixing various coloring substances on the phosphor particles.

According to this method, the light-emitting surface area of the phosphor is substantially reduced by the colored substance.

Therefore, especially for phosphors for low-speed electron beams, there is a problem in that the luminous efficiency is reduced.

In view of the above points, the present invention has a segment anode configured to have at least two different luminescent colors that can selectively emit light, and the color of the surrounding area surrounding the segment anode is determined by the luminescent color of the segment anode. By using a similar color to one of the two, the above-mentioned conventional problems are solved, and letters, numbers, figures, etc. can be displayed selectively even in brightly lit areas with many changes in brightness and darkness.

By emitting light of a color different from that of the segment anodes and similar to the color of the surface surrounding the segment anodes, the segment anodes that are not displayed are made to emit light with appropriate brightness, resulting in light emission with sufficient contrast. The object of the present invention is to provide a fluorescent display tube having a configuration that allows display to be obtained.

Hereinafter, the present invention will be explained in detail using the drawings.

FIG. 1 is a cutaway plan view of a main part showing a first embodiment of a fluorescent display tube according to the present invention, and FIG. 2 is an enlarged sectional view of the main part.

Here, 1 is a substrate made of glass or the like, including a top plate 2 having at least two transparent parts facing the display section, and an envelope 3 whose peripheral part is hermetically sealed to maintain a vacuum inside.
It consists of

4 is a wiring conductor formed on the substrate 1, and 5 is an insulating coating coated on the upper surface of the substrate 1 and the wiring conductor 4.

A plurality of anode conductors 6 are formed on the insulating film 5, and each anode conductor 6 has a connecting hole 7 provided in the insulating film 5.
The wiring conductors 4 are electrically connected to the corresponding wiring conductors 4 through the respective wiring conductors 4 .

A phosphor layer 8 is deposited on the upper surface of each anode conductor 6 to form a segment anode 9, and a group of segment anodes 9 forms a display section 1 for each digit.
0 is formed.

The figure shows an example in which a -digit display section 10 is formed by seven segment anodes 9 arranged in a figure-eight shape.

In the diagrammatic embodiment, each display section 10 is composed of seven segment anodes 9 arranged in a figure 8 shape. Of course, it can be constructed from an anode.

Reference numeral 11 denotes a mesh-like control electrode disposed above facing the display section 10, which controls the acceleration of electrons to the segment anode 9.

Reference numeral 12 denotes a filament-shaped cathode that is disposed above the display section 10 and the control electrode 11 and emits electrons when heated with electricity.

Here, each segment anode 9 is formed to have a configuration that allows it to selectively emit light in at least two different colors.

An embodiment that enables emission of light with these two types of emission colors will be described next.

That is, the phosphor layer 8 of the segment electrode 9 is formed by mixing two or more phosphors that emit light in different colors and have different threshold voltages.

For example, an example of forming the phosphor layer 9 that obtains two types of emitted light colors, green and red, includes a ZnO:Zn-based phosphor and a Y,202S:En+In203-based phosphor. is formed by appropriately mixing phosphors depending on the desired emission color.

Furthermore, a colored film 13 having a color similar to one of the emitted light colors obtained from the phosphor layer Btz is formed around the periphery surrounding each segment anode 9.

Here, the insulating film 5 is mixed with a coloring substance similar to one of the luminescent colors obtained in the above-mentioned phosphor layer 8.
It may also be formed to have a structure that also serves as the colored film 13.

Next, according to the embodiment of the fluorescent display tube of the present invention described above,
The action and effect will be explained.

That is, in the segment anode 9 that constitutes the display section 10,
A potential is selectively applied using one of the luminescent colors different from the color of the colored film 13 surrounding the segment anode 9 to display luminous characters and the like.

Similarly, for the segment anodes 9 that do not display characters, etc., the applied anode voltage is sequentially and selectively applied in a time-sharing manner, so that the segment anodes 9 are of the same type as the colored film 13 that is different from the colored light that displays characters, etc. The light is emitted according to the color of the other light.

Thus, the segment anode 9 is formed so that the emitted light color can be displayed in two types, red and green, and the surrounding colored film 1
If the segment anode 3 is formed, for example, in a pale red color (or green color), the emitted light color of characters, etc. on the display section 10 will be displayed in a green color (or red color), and the segment anode 9 that does not display characters, etc.
Red (or green), which is a similar color to the surrounding colored film 13
If it is made to emit light at an appropriate brightness, characters etc. to be displayed by emitting green (or red) light will be emitted by a colored film 13 of a red (or green) color different from this emitted light color and a red color which is not displayed. Surrounded by the segment anode 9, it floats and is not affected by the surrounding brightness.
It has the excellent feature of providing a luminescent display that is extremely easy to see.

In the first embodiment described above, the phosphor layer 9 is formed by mixing two types of phosphors with different emission colors and different emission threshold voltages, thereby producing two different emission colors. Although an example has been shown in which it is possible to obtain two or more different luminescent colors, the present invention is not limited to this example.

That is, a second actual case is shown.

FIG. 3 is a plan view of a main part of a display section showing a second embodiment of a fluorescent display tube according to the present invention.

The display section 10 in this embodiment is formed of seven segment anodes 9' arranged in a figure 8 shape as in the above-described embodiment, and further includes seven segment anodes 9'.
′ is a large number of small segments 5 (Sl, S2)
It is divided into

Therefore, the small segment S shown with diagonal lines in FIG.
1 and the small segment S2 without diagonal lines are coated with phosphor layers that emit light in different colors. For example, the small segment S1 has a Z phosphor layer that emits green light due to the impact of electrons.
A phosphor layer made of nO:Zn phosphor is deposited, and a phosphor layer made of Y2O2S:Eu mixed with a conductive material is deposited on the small segment S2, and a phosphor layer made of a phosphor that emits red color when bombarded with electrons. A body layer is applied.

Furthermore, the small segment S1 in the segment anode 9'. Each of S2 is divided into two systems for each luminescent color, electrically connected in common, and led out to an external terminal.
The area surrounding this segment anode 9' is formed of a colored film 13 having the same color as the emitted light color of one of the segment anodes 9' formed in two systems.

Next, the second
The operation and effect will be explained based on an example.

That is, in the segment anode 9' constituting the display section 10, a potential is selectively applied to the small segments S2 having a luminescent color different from the color of the colored film 13, thereby displaying characters or the like in color.

Similarly, for the segment anodes 9' that do not display characters or the like, a potential is applied to the small segments S1 to cause them to emit light with appropriate brightness.

However, as in the first embodiment described above, the segment 9' which does not display any characters or the like has almost the same color as the colored coating 13;
The brightness is the same, and it is visually buried within the colored film,
Segment 9', which displays characters, etc., comes to stand out.

In this way, since the display is distinguished not only by brightness but also by color, an extremely easy-to-read light-emitting display can be obtained without being affected by the surrounding brightness or darkness.

In addition, in this second embodiment, each segment 9' is divided into many strips, making it easy to adjust the brightness, and since the phosphor layer is independent, each color can be adjusted. Wide G, ) range can be selected.

Here, the above-mentioned fluorescent display tube according to the present invention has a filter disposed in front of the display section, and this filter has a color of light emitted from the segment anode for displaying characters, etc. If you use a filter that has the property of transmitting similar colors and observe the luminescent display on the display section through this filter, the luminescent display on the display section will match the luminescent color of the segment anodes that display characters, etc. , the difference between the emitted light color of the segment anodes that are not used for display and the color of the surface of the colored film surrounding the segment anodes is observed as a sharp contrast, so the segment anodes that display characters etc. , it has the excellent feature of providing a clearer and easier-to-see luminescent display, and its effects are extremely impressive.

As described above, according to the present invention, the segment anode is configured to have at least two different luminescent colors that can selectively emit light, and the color of the surrounding area surrounding the segment anode is determined by the segment anode. Since the configuration is such that the color is similar to one type of color, the segment anodes that do not display characters, etc. have almost the same color and the same brightness as the colored film, and are visually buried within the colored film, while also displaying characters, etc. It has an excellent feature in that the color of the emitted light from the segment anodes that provides the display can be observed to stand out clearly.

Therefore, it has the excellent feature of providing an extremely easy-to-read luminescent display with good contrast, and is extremely effective in improving the performance of fluorescent display tubes and expanding the range of applications.

In addition, in the present invention, if each segment is divided into many strips, the brightness can be easily adjusted, and since the phosphor layer is independent, each color can be selected from a wide range. It has the following excellent features.

[Brief explanation of the drawing]

FIG. 1 is a cutaway plan view of a main part showing a first embodiment of a fluorescent display tube according to the present invention, FIG. 2 is an enlarged sectional view of the main part, and FIG. 3 is a second embodiment. FIG. 3 is a plan view of main parts of the display section. 9.9'...Segment anode, 10...
- Pattern display portion, 13... Colored coating that is the peripheral portion surrounding the segment anode.

Claims (1)

[Scope of Claims] 1. A pattern display section formed by a plurality of segment anodes each having a phosphor layer deposited on the upper surface thereof, and electrons emitted from the cathode selectively impinge on the segment anodes. In the fluorescent display tube for displaying characters, numbers, figures, etc., each segment anode is configured to selectively emit light in at least two different colors;
In addition, one type of luminescent color of the segment anode and the color of at least the surrounding surface surrounding the segment anode of the pattern display section are arranged in similar colors, so that characters, numbers, and figures among the segment anodes are arranged in the same color. A segment anode that does not display luminescence, such as anode, is made to emit light in a luminescent color similar to the surrounding surface color, and this luminescent color is selectively used to display characters, numbers, figures, etc. A fluorescent display tube characterized in that it has a configuration that can be different from the emitted light color of an anode. Each two-segment anode emits a different color. 2. A phosphor display tube according to claim 1, further comprising a phosphor layer formed by mixing at least two types of phosphors having different emission threshold voltages. 3. The segment anode consists of a strip-shaped electrode divided into many pieces, and the divided electrodes are divided into at least two systems for each segment anode and electrically connected in common. 2. A phosphorescent display tube according to claim 1, wherein a phosphor layer is formed on the upper surface of the plurality of electrodes to emit light of a different color for each system.