JPH0439676B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a display panel using discharge tubes.

[Prior art] Conventionally, as a display panel of this type, the first one proposed by Aibitz under the product name "Letterlight"
The display panel shown in the figure was installed. In the figure, 1 is a cold cathode fluorescent discharge tube, and there are two discharge tubes 1a and 1b.
The letter "O" in Alphabet is formed by deforming the same, and the letter "P" in Alphabetical is formed by similarly using two discharge tubes 1c and 1d. Cases 2a and 2b are cases in which the above-mentioned "O" and "P" discharge tubes are fixed with adhesive, etc.
A display panel is constructed by connecting the terminals 3a to 3h of the discharge tubes 1a to 1d to circuit components (not shown) housed inside. 4 is the guide that secures this display panel with magnets.
4a and 4b are electrode guides that supply electricity to the discharge tube 1, and 4c and 4d are signal electrode guides that cause the discharge tube 1 to blink.

FIG. 2 is an enlarged sectional view of the discharge tube 1. The discharge tube 1 is generally a glass tube 5 with an external diameter of 3 to 15 mmφ, and is housed in a vacuum sealed container with a fluorescent material 6 coated on the inner surface, and a discharge is caused from the electrodes. The fluorescent material 6 is configured to emit light, and depending on the type of fluorescent material 6, the color can be green, red, orange, peach, or
Emission colors such as blue and white can be obtained. Incidentally, since the light emissions 7a to 7h shown by the arrows of the discharge tube 1 extend all around the discharge tube, the light emissions 7f to 7h from the viewer 8 and the back side are absorbed or scattered by the case 2 and contribute little to the display. As a result, this type of display panel has low brightness, and in particular, when displaying blue and white colors, combined with the poor luminous efficiency of the fluorescent material 6, only low visibility can be obtained. Furthermore, for example, since green fluorescent materials generally have higher luminance than fluorescent materials of other colors, display panels have the disadvantage of unavoidable variations in brightness due to differences in color.

[Summary of the invention]

This invention was made with the aim of improving these drawbacks, and by providing a diffused light-shielding slit on the inner surface of the glass tube of the discharge tube, it is possible to increase display brightness and eliminate variations in brightness due to differences in display colors. The objective is to provide a display panel with a

[Embodiments of the invention]

Embodiments of the present invention will be described below with reference to the drawings.
In FIG. 3, the same reference numerals as in FIG. 2 indicate the same parts. 9 is a diffused light-shielding slit provided on the inner surface of the glass tube 5 on the case 2 side of the discharge tube 1;
A fluorescent material 6 is coated on the entire inner surface of the glass tube 5 including the surface thereof. The angle θ of the diffused light shielding slit 9 is preferably 240 degrees or less. Diffuse light shielding slit 9
Due to this formation, the light emitted from the discharge tube 1 7f to 7h can be suppressed within the glass tube 5, diffused, and emitted from the viewer 8 side. As a material for the slit 9, a white fluorescent material having a lower luminous efficiency than the fluorescent material 6, titanium oxide, or the like is effective, and the thickness of the slit 9 may be sufficient as long as it can diffuse and block the light emitted from 7f to 7h. The method for applying the slits 9 is to first apply the diffused light shielding slits 9 on the inner surface of the glass tube 5 within a range of an angle θ, and then apply the fluorescent material 6 to the entire inside of the glass tube 5 from that surface.

4 to 7 show various embodiments of the diffused light shielding slit 9, and FIG. 4 shows an example in which the slit 9a is continuously provided over the entire length of the discharge tube 1. Note that 10a and 10b are terminals 3 of the discharge tube 1.
and lead wires that connect to circuit components inside the case (not shown). The slit 9b in Fig. 5 is the discharge tube 1.
In this example, in the case of a display panel in which a plurality of discharge tubes 1 having different emission brightnesses are assembled, uniform display brightness can be achieved by controlling the slit width W. Figures 6 and 7
The slit 9a in the figure shows an example in which the area is gradually changed in the longitudinal direction of the discharge tube 1.
The emission brightness distribution within the discharge tube 1 can be corrected, and a display panel with uniform display brightness can be obtained.

In the above embodiments, the discharge tube is a straight tube, but the same effect can be obtained even if the discharge tube is a curved tube. In addition to cold cathode fluorescent discharge tubes, discharge tubes include cold cathode fluorescent discharge tubes,
The same method can be used for simple discharge tubes and fluorescent discharge tubes.

〔Effect of the invention〕

As explained above, according to the present invention, by providing the diffused light-shielding slit on the inner surface of the glass tube of the discharge tube, display brightness can be increased, and variations in brightness due to differences in display colors can be eliminated, and visual A display panel with good performance can be obtained.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a conventional display panel, FIG. 2 is an enlarged sectional view of a discharge tube, FIG. 3 is an enlarged sectional view of a discharge tube of a display panel according to the present invention, and FIGS.
FIG. 7 is a side view and a longitudinal cross-sectional view of a discharge tube showing various examples of diffused light-shielding slits. 1...Cold cathode discharge tube, 5...Glass tube, 6...
Fluorescent material, 9, 9a, 9b, 9c... Diffusion light shielding slit. In addition, in the figures, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Scope of Claims] 1. A display panel comprising a plurality of discharge tubes deformed into a display shape such as characters, characterized in that a diffused light-shielding slit is provided on the inner surface of the glass tube of the discharge tube. 2. The display panel according to claim 1, wherein the discharge tube is a fluorescent discharge tube. 3. The display panel according to claim 1, wherein the discharge tube is a cold cathode discharge tube. 4. The display panel according to any one of claims 1 to 3, wherein the diffused light-shielding slit is provided over the entire length of the discharge tube. 5. The display panel according to any one of claims 1 to 3, wherein the diffused light-shielding slits are provided intermittently along the longitudinal direction of the discharge tube. 6. The display panel according to any one of claims 1 to 3, wherein the diffused light-shielding slit is provided with its area gradually changing in the longitudinal direction of the discharge tube.