JP2923388B2 - Fluorescent lamp for display element - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluorescent lamp for a display element which forms pixels of a large color display device or the like which is mainly installed in an outdoor stadium or the like.

[0002]

2. Description of the Related Art As a fluorescent lamp for a display element forming pixels of a large color display device, as shown in FIG. 2, a plurality of light emitting chambers 1R, 1G, 1 forming one pixel.
A structure in which one discharge space is formed by connecting B and 1G and a common cathode 22 is provided in this discharge space has been put to practical use.

This fluorescent lamp includes a light source tube 10,
The internal space of the light source tube 10 is partitioned by a partition 11, and for example, four light-emitting chambers 1R, 1G, 1B, 1G are formed. In each of the light emitting chambers 1R, 1G, 1B, 1G, a long discharge path is formed by the partition plate 12. Each lighting room 1
Different emission colors, for example, 1R is red, 1G is green, and 1B is blue, a phosphor that emits blue light is attached to the inner surfaces of R, 1G, 1B, and 1G.

In each of the light emitting chambers 1R, 1G, 1B, and 1G, communication holes 2R, 2G, 2B, and 2G are formed at one location near the center of the light source tube 10, and anodes 3R are provided at other locations. , 3G, 3B, and 3G are arranged.

The light source tube 10 is formed of a non-translucent material such as ceramics having a relatively high reflectance to visible light, and a translucent glass plate 30 is sealed on the upper surface (display surface). ing. On the lower surface of the light source tube 10, a glass bulb 20 as an electrode chamber is sealed so as to cover the communication holes 2R, 2G, 2B, 2G. Cathode 22
Is provided. The above components are hermetically sealed with a glass frit.

As described above, the inner space defined by the light source tube 10, the glass plate 30, and the bulb 20 communicates through the communication holes 2R, 2G, 2B, 2G to form an airtight one.
One discharge space is formed, and a discharge gas including an inert gas such as argon and mercury is sealed in the discharge space.

In the fluorescent lamp having such a configuration, when a discharge is made between the desired anodes 3R, 3G, 3B, 3G and the common cathode 22, the anodes 3R, 3G, 3 involved in the discharge are discharged.
The light emitting chambers 1R, 1G, 1B, and 1G corresponding to B and 3G emit light, and can emit a desired color.

[0008]

In the above fluorescent lamp for a display element, the light source tube 10 is made of forsterite ceramic, the glass bulb 20 is made of soda-lime glass, and the glass plate 30 is made of soda-lime glass. However, since the glass plate 30 is rich in alkali metal components and its inner surface is in direct contact with the discharge space and is exposed to mercury vapor discharge, the glass plate 30 forms an absorption film of alkali amalgam, The mercury ion causes an ion exchange reaction due to the similarity of the ion radius, and an absorption layer is formed.

As a result, remarkable blackening of the glass occurs on the inner surface of the glass plate 30 after lighting for several hundred hours, resulting in a large decrease in luminance. As a result of analysis, it was found that the components of this glass blackening were mainly mercury oxide and sodium amalgam.

An object of the present invention is to provide a fluorescent lamp for a display element in which the inner surface of a glass plate does not become blackened even after being lit for a long time. It is in.

[0011]

In order to solve the above-mentioned problems, the present invention has a light-transmitting glass plate sealed on the upper surface,
A light source tube body having a plurality of light emitting chambers each having a phosphor adhered to an inner surface thereof; an electrode chamber hermetically sealed to a lower surface of the light source tube body so as to form a discharge space communicating with each light emitting chamber; A plurality of anodes respectively disposed in the light-emitting chamber, and one common cathode disposed in the electrode chamber; a discharge gas is sealed in the discharge space; When a voltage causing a discharge is applied between the metal alcoholate solution in a fluorescent lamp for a display element in which a phosphor in a light emitting chamber in which an anode causing a discharge is disposed emits light .
The glass plate
The entire surface including the sealing portion with the light source tube is provided on the surface.
A lumina layer is provided.

[0012]

Embodiment 1 In order to prevent the above-mentioned blackening of the glass, it is necessary to avoid contact between the glass surface rich in alkali metal and the discharge surface. For this purpose, the present inventors have studied various glass protective films.

First, ultrafine titanium oxide, alumina,
Coating experiments were performed on cerium oxide, zirconium oxide and zinc oxide.
Even if these films are formed on the surface of the light source tube 10,
At the time of sealing, these films are peeled off, or poor sealing such as leaks continues to cause a problem in manufacturing.

[0014] In view of the above, an attempt was made to form a film using a metal alcoholate solution to solve the above production problems, and found that among the above-mentioned protective film materials, those having an alumina layer provided on the surface of a glass plate exhibit good characteristics. Was.

Hereinafter, a film formation using a metal alcoholate solution will be described. First, the required number of glass plates is 1
A substrate glass having a size of 0 sheets is prepared and degreased. This substrate glass is immersed vertically in a metal alcoholate coating solution and pulled up at a speed of 200 to 300 mm / min.
After drying at room temperature for about 30 minutes, baking is performed at 500 ° C. for 1 hour to obtain a desired metal oxide film. The thickness of the metal oxide thus obtained was 500 to 1000 °. Finally, this substrate glass is cut to a predetermined size,
The glass plate 30 was provided.

In the film formation using the metal alcoholate solution, the film was formed densely, and there was no problem of peeling or leakage of the protective film which occurred in the case of the ultrafine particle type film, and it was confirmed that there was no problem in production.

FIG. 1 shows the spectral transmittance characteristics of the obtained glass plate with a protective film. In the figure, A is without a protective film, B is alumina (Al ₂ O ₃ ), and C is zinc oxide (Zn).
O) and D indicate the characteristics of zirconium oxide (ZrO ₂ ), E indicates the characteristics of cerium oxide (CeO ₂ ), and F indicates the characteristics of titanium oxide (TiO ₂ ).

As is clear from the characteristic diagram shown in FIG. 1, only alumina in the protective film does not lower the transmittance of the substrate glass. Therefore, even if the alumina protective film is formed on the surface of the glass plate 30, the brightness of the lamp is not reduced.

This means that the circuit constants of the lighting control circuit of the lamp according to the present invention may be exactly the same as in the prior art, and complete compatibility is maintained.

FIG. 2 is an enlarged sectional view of a main part of a fluorescent lamp for a display element according to the present invention. The glass plate 30 having the alumina layer 31 formed on the surfaces thereof by the above-described film forming method and the light source tube 10 are sealed. Shows the state of wearing.

FIG. 3 shows the results of an acceleration test of the relative luminance maintenance ratio with respect to the lighting time of a fluorescent lamp for a display element using a glass plate having no protective film and a glass plate having an alumina protective film formed thereon. In the figure, A shows the characteristics of a film without the protective film, B shows the characteristics of the film formed with the alumina protective film (applied once), and C shows the characteristics of the film of the film coated with the alumina protective film twice.

[0022]

Example 2 In the alumina layer obtained by the dip-and-pull coating method using a metal alcoholate solution, since the solvent of the coating solution evaporates and evaporates during drying, voids remain after the solvent is removed, and some defects are found in the film. Exists. For this reason, at the time of lighting for a long period of time of several thousand hours, the conventional blackening of the glass occurred, albeit slightly.

In this embodiment, in order to reduce the defects of the alumina layer, dip-pull coating is performed a plurality of times. In the film forming process, immersion pulling, drying, and baking are repeated a plurality of times.

As is apparent from the characteristic C shown in FIG.
By repeated application, glass blackening could be almost completely prevented. Specifically, the luminance half-life of the conventional fluorescent lamp for a display element was about 8000 hours, whereas in the present embodiment, it was extended to 20,000 hours or more.

[0025]

As described above, the present invention relates to a metal alcohol
The alumina layer was provided on the entire surface of the glass plate including the sealing portion with the light source tube by the dip-and-pull coating method using a glass solution. The direct contact of the surface was avoided, resulting in a light source
Glass blackening can be prevented to the vicinity of the sealed portion of the tube body, a long period of time it is possible to maintain high luminance even after lighting, i.e. fluorescent lamp display element having a long lifetime can be obtained. Moreover, the metal A
Provided by dipping and pulling coating method using rucolate solution
The obtained alumina layer has a thickness of 500 to 1000 °.
In addition to being extremely thin so that the linear expansion coefficient can be ignored.
Also, since there is no problem of peeling or leakage, sealing with the light source tube
Even if it is provided in the attachment part, the light source tube and the glass plate
There is no trouble in sealing.

Further, since the alumina layer formed by the dip-and-pull coating method using a metal alcoholate solution is a dense continuous film, there is no problem of peeling of the film or defective sealing caused by the ultrafine particle type protective film, and it is easy to manufacture. It is.

Furthermore, the dip-and-pull coating method using a metal alcoholate solution can coat a large amount of substrate glass at a time, so that mass productivity is high. Therefore, if an alumina layer is formed by this method, the cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a spectral transmittance characteristic diagram of a glass plate with a protective film.

FIG. 2 is an enlarged sectional view of a main part of a fluorescent lamp for a display element according to the present invention.

FIG. 3 is a graph showing a result of an acceleration test of a relative luminance maintenance ratio with respect to a lighting time of a fluorescent lamp for a display element.

FIG. 4 shows an example of a fluorescent lamp for a display element.
(A) is a plan view and (b) is a cross-sectional view. DESCRIPTION OF SYMBOLS 1 Emission room 2 Communication hole 3 Anode 10 Light source tube 20 Electrode room 22 Common cathode 30 Glass plate 31 Alumina layer

Claims (1)

(57) [Claims] 1. A light source tube having a plurality of light-emitting chambers each having a light-transmitting glass plate sealed on an upper surface and a phosphor attached to an inner surface thereof, and a discharge space communicating with each light-emitting chamber. An electrode chamber hermetically sealed to the lower surface of the light source tube so that
A plurality of anodes respectively disposed in each light emitting chamber, and one common cathode disposed in the electrode chamber, a discharge gas is sealed in the discharge space, and a desired anode and common cathode In a fluorescent lamp for a display element, in which a fluorescent substance in a light emitting chamber in which an anode generating a discharge is disposed emits light when a voltage causing a discharge is applied, a metal alcoholate solution is used.
With immersion pulling coating by, over the entire surface including the sealing portion of the light source Kankarada the surface of the glass plate
A fluorescent lamp for a display element, characterized in that an alumina layer is provided.