JPH0335772B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a fluorescent display device, and particularly to a fluorescent display device of the type in which light emission from a phosphor layer is observed from the other side of a transparent substrate having an anode portion formed on one side. This invention relates to display devices.

Electrons emitted from the heated cathode are selectively bombarded with a phosphor-coated anode to create letters and letters.
Fluorescent display devices that display graphics, etc. have features such as a good luminescent color, can be driven at low voltage, and have low power consumption, so they are often used as display devices for electronic devices, etc. ing.

Incidentally, there are two types of fluorescent display devices: one is a type formed on an insulating substrate and the light emitted from the anode part with a phosphor layer applied to the top surface is observed through the grid, cathode, and front container, and the other type is a type in which the substrate is transparent. A type that uses a substrate, and the electrode that forms the anode part is formed from a transparent conductive film, and the anode part, grid, cathode, etc. are covered with a back container, and the light emission of the phosphor layer is observed from the transparent substrate side. There is.

In any of the above types of fluorescent display devices, if a multi-purpose pattern display section is provided, so-called compounding, in a single display device, the display device itself will be large, so voltage resistance must be taken into account. Therefore, it is necessary to strengthen the structure of the vacuum-tight envelope consisting of the substrate and the front container or rear container. Therefore, in the past, a method of increasing the thickness of the substrate and the front container or the rear container, or a method of providing reinforcement by providing a reinforcing member interposed between the substrate and the container portion inside was used. However, the above-mentioned method of increasing the thickness of the plate increases the weight, the molding process of the container part is complicated and expensive, and the formation of each electrode part and its attachment work are complicated. However, the method of providing a reinforcing member is difficult to manufacture, reduces work efficiency, and has the problem of narrowing the viewing angle, especially in the case of a type in which the display is viewed from the front side of the container. It is also possible to construct a composite display device by assembling a large number of small fluorescent display tubes, but a special structure is provided to hold each display tube so that its display surface is on the same plane. This inevitably increases the size of the display device as a whole, and there are also problems in terms of appearance and the wiring to each display tube becomes complicated.

The present invention has been made in view of the above points, and it is an object of the present invention to observe a display from the other side of a light-transmitting substrate made of an insulating material and having a phosphor layer adhered to one side. In the fluorescent display device as described above, the pattern display section is divided into a plurality of parts,
The above-mentioned conventional problems are solved by a configuration in which separate rear containers are attached to each section,
It is an object of the present invention to provide a large-sized fluorescent display device that can be easily and inexpensively manufactured and has a good appearance.

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

FIG. 1 is a front view of an embodiment of a fluorescent display device according to the present invention as seen from the observation side, FIG. 2 is a rear view of the same, and FIG. Figure 4 is an enlarged sectional view of the main parts, and Figure 5 is
FIG. 2 is an enlarged perspective view of a main part of the drive circuit section.

In the figure, reference numeral 1 denotes a light-transmitting substrate made of an insulating material, such as glass, and a display pattern used in an industrial measurement panel is formed on this substrate 1. That is, when viewed from the front of the observation side of the board 1, from above, there are a DC milliampere pattern display section 111, a DC millivolt pattern display section 112, a temperature pattern display section 113, an AC amperage pattern display section 114,
Dot matrix message pattern display section 1
15 is formed, and each pattern display section 1
On the back side 1a of the board at positions corresponding to 11 to 115,
First to fifth rear containers 211 to 215 are attached, respectively.

The back containers 211 to 215 are connected to each other by a communication exhaust pipe 15, so that the interiors of the back containers 211 to 215 are in communication with each other. However, the above-mentioned rear container 21
An outwardly protruding exhaust pipe 16 is formed on the back of one of the containers 1 to 215, in this embodiment, the third rear container 213, and this exhaust pipe 16 is sealed after exhaustion. On the other hand, a filter 17 of an appropriate color and density is attached to the front surface of the substrate 1 as required. Furthermore, the back side 1 of the above board
An integrated drive circuit section 2 including a decoder circuit, a driver circuit, etc. is installed at a location in a where each of the rear containers 211 to 215 is not attached.
is attached, and an external lead terminal 3 is formed on a part of the outer peripheral edge of the substrate 1. Although not shown in FIG. 2, wiring conductors connecting each of the pattern display sections 111 to 115 and the drive circuit section 2 and the drive circuit section 2 and the lead terminals 3 are covered on the back surface 1a. It is formed.

Furthermore, the internal structure of the fluorescent display device according to this embodiment will be explained with reference to the enlarged sectional view of FIG.

On the back surface 1a of the substrate 1, a pattern of anode conductors divided according to the shape of each divided display pattern and the number of anode parts, and a transparent conductive film 4 serving as the lead wires is formed. A translucent or opaque insulating film 5 is formed on the back surface 1a of the substrate 1 on which the conductive film 4 is formed, leaving a transparent electrode portion 4a corresponding to the shape of the anode portion. Further, a phosphor layer 6 is provided on the anode-shaped transparent electrode portion 4a on which the insulating film 5 is not applied.
The transparent conductive film 4 covered with the insulating film 5 is used as a lead wire 4b to connect to the transparent conductive film 4 of another pattern display part or the external wiring 7 and the through hole. 8. In addition, the insulating film 5 has
If necessary, a conductive film 5a is applied to prevent static electricity. Further, a grid 9 is disposed so as to cover the back surface of each of the phosphor layers 6, and a cathode 10 is stretched further behind the grid 9. Therefore, each pattern display section 111
~ 115, the phosphor layer 6, the grid 9
The back containers 211 to 215 are attached to the back surface 1a side of the substrate 1 so as to contain the cathode 10. The back containers 211 to 215 are box-shaped or flat-bottomed boat-shaped as shown in the figure, and a conductive film 11 is coated on the inner surface for preventing static electricity and preventing the influence of an external electric field. is, for example, electrically connected to the cathode 10 or to the grid 9, or separately led out to the external wiring 7 to maintain an appropriate potential between the cathode potential and the anode potential. It may also be provided. A vacuum-tight envelope 12 is made of the back containers 211 to 215 and the substrate 1. Further, the grid 9, the cathode 10, and the transparent electrode section 4a are connected to the drive circuit section 2 via the external wiring 7. As shown in FIG. 5, this drive circuit section 2 has, for example, a flat package structure, and each terminal 2a is directly connected to the external wiring 7 with a conductive adhesive such as solder 14 and fixed. The input terminal of this drive circuit section 2 is also connected to the external lead terminal 3 via an external wiring 7 or the like. In addition, as a method for connecting the drive circuit section 2 and the external wiring 7, it is of course possible to adopt a wire bonding method, a face-down bonding method, or the like as appropriate.

By the way, if the conductive film 11 is formed of a light-absorbing substance, for example, a black conductive film such as graphite, the light emitted from the phosphor layer 6 emitted toward the rear containers 211 to 215 is absorbed by the conductive film 11. This prevents the problem of the emitted light being reflected by the conductive film and irradiating the non-emitting anode portion, resulting in a decrease in contrast between the non-emitting anode portion and the emitting anode portion.

By the way, as a method for forming the anode part,
Although various methods can be considered, for example, in this example, the following method was used.

First, on the back surface 1a of the substrate 1, a pattern of the transparent conductive film 4 divided according to the anode portion and its wiring conductor pattern is formed. This pattern may be formed by depositing the transparent conductive film 4 all over the substrate 1 and then removing unnecessary portions by photolithography, or by using a mask vapor deposition method. The transparent conductive film 4 may be directly deposited on the substrate 1 in a desired pattern.

Next, transparent electrode portions 4 corresponding to the segment shapes are placed on the substrate 1 on which the pattern of the transparent conductive film 4 is formed.
a. The insulating film 5 is formed by applying a material mainly composed of, for example, low-melting fritted glass, by screen printing, leaving the grid and the connecting portion between the filament and the wiring, and then baking it.

In this case, a pigment is mixed into the material that will become the insulating film 5 to color it so that the insulating film 5 becomes optically translucent or opaque.

The insulating film 5 may have any color as long as it is translucent or opaque, but it is preferably a color similar to the color of the phosphor layer 6 deposited in the next step when it is not emitting light.

Next, a phosphor layer 6 is applied to the anode portion of the transparent electrode portion 4a that is not covered with the insulating film 5. The deposition method may be any method such as a precipitation method, a screen printing method, an electrodeposition method, a slurry method, etc. In this case, the phosphor layer 6 to be deposited can be
The thickness of the phosphor layer 6 is preferably as thin as possible because the emitted light is extracted to the outside through the phosphor layer 6.

Next, a conductive material is deposited on the insulating film 5 by, for example, screen printing to form the external wiring 7.

After that, install the grid 9, cathode 10, and back containers 211 to 215 using the usual procedure, and
The inside of each envelope 12 is evacuated through the individual exhaust pipes 16 to create a high vacuum atmosphere and hermetically sealed, and the drive circuit section 2 is connected to each wiring 7 with solder 14 and fixed. good.

When an external power source is connected to the fluorescent display device thus constructed, electrons emitted from the cathode 10 impinge on the phosphor layer 6, causing the phosphor layer 6 to emit light. This phosphor layer 6 emits light from the phosphor layer 6,
Light transmitted through the transparent electrode section 4a and the substrate 1 and observed from the front of the substrate 1, and emitted by the phosphor layer 6 toward the inside, that is, toward the grid 9, is absorbed by the conductive film 11 and the insulating film 5. will be done.
This eliminates the possibility that light will be perceived as leaking from the anode portion that is not emitting light.

The fluorescent display device has a large number of pattern display sections 111 to 115, and is large in size.
5 is attached, each vacuum-tight envelope 12 has a volume comparable to that of a small fluorescent display tube. Therefore, it does not require special considerations such as making the vacuum envelope particularly strong to withstand pressure, which was required for conventional large-sized fluorescent display devices, and it can be used for conventional small fluorescent display devices. A large-sized display device can be easily created using optical display tube technology.

Note that the present invention is not limited to the embodiments described above and shown in the drawings. For example, in each of the embodiments described above, a light shielding property is Wear a mask of
Alternatively, in the case of multicolor display, various modifications may be made without changing the gist of the invention, such as providing a filter corresponding to the color of light emitted by each display section on the front surface of the substrate 1.

As described above, a fluorescent display device according to the present invention is a fluorescent display device in which a display is observed from the other side of an insulating transparent substrate having a phosphor layer coated on one side. , the pattern display section is divided into a plurality of sections, and a separate and mutually independent rear container is attached to each section, so that a large-sized fluorescent display device having a large number of pattern display sections can be achieved. However, each vacuum-tight envelope can be constructed with a volume comparable to that of a small fluorescent display tube, and in order to maintain pressure resistance, it is necessary, for example, to increase the thickness of the envelope constituent material or add reinforcing members. It has the advantage that it does not require special considerations such as making the vacuum envelope particularly strong. Therefore, it is possible to easily and inexpensively create a large-sized fluorescent display device using conventional technology, and since there is no need to thicken the substrate or rear container, the weight of the device can be reduced and it can be mounted on a vehicle. When the fluorescent display device of the present invention is used as a commercial device, excellent effects such as low fuel consumption can be obtained.

Furthermore, in the fluorescent display device of the present invention, the mounting structure of electrodes such as grids and cathodes, and the sealing structure of the rear container can be handled in the same way as in the case of conventional small fluorescent display tubes, so the work is easy. The process can be prevented from becoming complicated, and from this point of view as well, the manufacturing cost can be reduced.

Furthermore, in the fluorescent display device of the present invention, each pattern display section is formed on a common substrate, so it is possible to significantly improve the ratio of the display surface to the entire substrate, the so-called display space factor. In addition, parts common to each envelope part, such as cathode lead wiring, external lead terminals, and duplexes, can be integrated on the board, reducing the number of parts.
Furthermore, wiring can be done on the board surface between each pattern display area, which is divided by the attachment of the rear container, resulting in high reliability and less soldering work for wiring, increasing work efficiency. The effect obtained is extremely large.

Furthermore, the depth of each of the plurality of divided envelope parts to which the rear container is attached varies in length or short depending on the size of each pattern display section or the drive type, and unevenness occurs depending on the height of the rear container. However, in the fluorescent display device of the present invention, since the display surface of each envelope portion is on the same plane as the substrate surface, the unevenness of each rear container may obstruct visual viewing or interfere with use. It has excellent effects as a large-sized fluorescent display device of the type in which the display is observed through a substrate, such as being easy to use and providing an easy-to-see display.

Further, according to the present invention, at least two back containers are connected by a communicating exhaust pipe so that they communicate with each other, so that the inside of the back containers that are communicated with each other can be evacuated in one exhaust operation. This has the excellent effect of greatly improving the efficiency of the exhaust work.

[Brief explanation of the drawing]

FIG. 1 is a front view of an embodiment of a fluorescent display device according to the present invention as seen from the observation side, FIG. 2 is a rear view of the same, FIG. The figure is an enlarged sectional view of the main part, and FIG. 5 is an enlarged perspective view of the main part showing the drive circuit section. DESCRIPTION OF SYMBOLS 1... Substrate, 2... Drive circuit part, 4... Transparent conductive film, 6... Phosphor layer, 10... Cathode, 12...
...Envelope, 15...Communication exhaust pipe, 16...Exhaust pipe, 111-115...Pattern display section, 211
~215...Back container.

Claims (1)

[Scope of Claims] 1. A pattern in which an anode part made of a transparent conductive film and a phosphor layer coated on the upper surface is arranged on one side of a transparent substrate made of an insulating material according to a display pattern. A display section is formed, and by applying a display signal from the drive circuit section to this pattern display section via an energizing means, electrons emitted from the heated cathode are bombarded to emit light, and this phosphor layer In a fluorescent display device whose light emission is observed from the other side of the substrate, a pattern display area formed on the substrate is divided into at least two or more parts, and the divided pattern display area is divided into two parts. a rear container made of at least two or more mutually independent members forming divided envelope parts that cover each of the parts and maintain a space formed between the substrate and the substrate in a high vacuum atmosphere. A fluorescent display device, characterized in that at least two of the rear containers are internally communicated with each other by a communication exhaust pipe made of a separate member separated from each rear container. 2. The fluorescent display according to claim 1, wherein the means for supplying electricity to the pattern display section extends outside the rear container forming each of the envelope portions and is disposed on the substrate. Device. 3. The fluorescent display device according to claim 1 or 2, wherein the drive circuit section extends outside the rear container and is directly connected to a current supply means provided on the substrate. .