KR20020020638A - Bi-planar Vacuum Fluorescent Display Device - Google Patents

Abstract

PURPOSE: To provide a biplaner display tube that has a structure in which the display by the anode 14 of the rear substrate 11 is made suitable for creating a background display effect on the display by the anode 16 of the front substrate 12. CONSTITUTION: The inner face 121 of the front substrate 12 is made coarse and an anode electrode 161 is formed on the inner face 121 and further, a phosphor 162 is painted on it. The emitted lights of the anode 14 scatter on the inner face 121 that is made coarse, but the emitted lights of the anode 16 are not affected by the scattering and are displayed clearly as the anode 16 is formed closely contacted on the inner face 121. Accordingly the observer can view the display of the anode 16 with the scattered lights of the anode 14 in the background.

Description

Bi-planar Vacuum Fluorescent Display Device

The present invention relates to a biplanar fluorescent display tube in which anode electrodes are formed on both substrates of a front substrate and a back substrate.

5A is a perspective view of a conventional biplanar fluorescent display tube, and FIG. 5B is a cross-sectional view of the X-X portion of FIG. 5A.

Reference numeral 41 denotes a rear substrate, reference numeral 42 denotes a front substrate, reference numerals 431 to 433 denote side plates, reference numerals 44 and 46 denote an anode coated with a phosphor on an anode electrode, and reference numeral 45 And 47) are grids, and 48 is a filament for the cathode.

The biplanar fluorescent display tube is a type of fluorescent display tube which observes light emission of the anodes 44 and 46 from the outside of the front substrate 42.

The anode 44 and the grid 45, the anode 46 and the grid 47 are paired, respectively, and the independent display is performed by electrons from the filament 48 common to both pairs. For example, the anode 46 performs digital display in a seven segment pattern, and the anode 44 performs analog display in a bar pattern. As such, the bi-planar fluorescent display tube acts as if two pairs of anode and grid are independent of the two fluorescent display tubes. Therefore, the biplanar fluorescent display tube has a structure capable of clearly viewing light emitted from the anode 44 and the anode 46, respectively.

Since the fluorescent display tube uses low-speed electrons, it emits light near the surface of the phosphor. Therefore, in the biplanar fluorescent display tube, the light emission of the anode 44 can be directly observed, but the light emission of the anode 46 observes the light transmitted through the phosphor (the light emission of the surface of the phosphor is observed from the inside). ). Therefore, even though the anode 44 and the anode 46 have the same emission luminance, the light emitting side of the anode 44 appears brighter to the observer outside the front substrate 42.

In the present invention, in the biplanar fluorescent display tube, of the two anodes, the anode (back anode) of the back substrate is for generating a background effect on the display of the anode (front anode) of the front substrate, that is, the backlight effect. It is an object of the present invention to provide a bi-planar fluorescent display tube having a structure that can be used for the creation of an anode, to make the display of the front anode stand out, or to enrich the expression of the display.

By the way, the conventional bi-planar fluorescent display tube is comprised so that the display of both front and back anodes can be visually recognized clearly. Therefore, the display of the back anode is clearly visible in bar or dot light emission, and is not effective as a background display. Further, as described above, the light emission of the rear anode became brighter than the light emission of the front anode, which was not effective as the background display.

In view of this, an object of the present invention is to provide a biplanar fluorescent display tube having a structure suitable for generating a background effect by imparting a light scattering function to a front substrate.

The present invention provides a biplanar fluorescent display tube comprising a front substrate having an anode electrode coated with a phosphor on an inner surface thereof, a rear substrate formed with an anode electrode coated with a phosphor on an inner surface thereof, and a cathode disposed between both substrates. The inner surface of the front substrate is roughened.

In the biplanar fluorescent display tube of the present invention, the anode electrode formed on the front substrate is made of a transparent conductive material.

According to the present invention, in the biplanar fluorescent display tube, the anode electrode formed on the front substrate is made of a non-transmissive conductive material and has transparency.

In the biplanar fluorescent display tube of the present invention, an anode is formed on a smoothing layer made of a transparent insulating material formed on an inner surface of a front substrate.

1 is a cross-sectional view of a biplanar fluorescent display tube according to an embodiment of the present invention;

2 is an enlarged cross-sectional view of an anode according to an embodiment of the present invention;

3 is a view for explaining the action of the roughened inner surface of the front substrate according to the embodiment of the present invention,

4 is a diagram showing the relationship between the roughness of the rough surface of the front substrate according to the embodiment of the present invention and the rate of increase of electric resistance values such as wiring;

5 is a perspective view and a cross-sectional view of a conventional biplanar fluorescent display tube.

Explanation of symbols for the main parts of the drawings

DESCRIPTION OF SYMBOLS 1 Glass back substrate 12 Glass front substrate

121: inner surface of the front substrate 13: side plate of glass

14, 16: anode 141, 161: anode electrode

142, 162: phosphors 15, 17: grid

163: smoothing layer 164: transparent anode electrode

18: filament for the cathode 19: enlarged portion

1 is a cross-sectional view of a biplanar fluorescent display tube according to an embodiment of the present invention, in which FIG. 1A shows a cross-sectional view of a portion corresponding to part XX in FIG. 5A, and FIG. 1B shows a portion 19 surrounded by a broken line in FIG. 1A. ) Shows an enlarged view.

Reference numeral 11 is a back substrate of glass, reference numeral 12 is a front substrate of glass, reference numeral 121 is an inner surface of the front substrate 12, reference numeral 13 is a side plate of glass, reference numeral ( 14, an anode, reference numeral 15 is a grid, reference numeral 16 is an anode, reference numeral 17 is a grid, and reference numeral 18 is a filament for a cathode.

The anode 14 is composed of a bar pattern, and the anode 16 is composed of a seven segment pattern.

The inner surface 121 of the front substrate 12 is roughened by forming irregularities as shown in FIG. 1B by a sandblast or the like described later. An anode electrode 161 constituting the anode segment is formed on the roughened inner surface 121, and a phosphor 162 is applied to each segment. The anode electrode 161 may be formed of a transparent conductive material such as ITO, or may be formed by forming a slit, a hole, or the like in a conductive material film (non-transmissive conductive material film) such as aluminum. In this case, the light emitted from the phosphor 162 is transmitted through the slit or the like and is radiated to the outside of the front substrate 12.

Here, the light emitted from the front substrate 12 and back substrate 11 will be described with reference to FIG. 3.

The light emitted by the phosphor 142 applied to the anode electrode 141 of the rear substrate 11 has some spreadability on the inner surface 121 of the front substrate 12 as shown by reference numeral H of FIG. 3. It goes straight and scatters in the multi-direction like the reference numerals h1, h2, h3 on the rough surface of the inner surface 121. Therefore, since the observer outside the front substrate 12 observes the scattered light of the light emitted by the phosphor 142 of the back substrate 11, the observer only observes the individual emitted light of the anode electrode 141. Instead, the scattered light of adjacent anode electrodes is also observed at the same time. Therefore, the boundary of light emission of each anode electrode 141 becomes inconspicuous, resulting in a smooth background display with a uniform front surface.

On the other hand, since the anode electrode 161 and the phosphor 162 of the front substrate 12 are formed in close contact with the inner surface 121 of the front substrate 12, the observer is hardly affected by scattering of the inner surface 121. Without light emission of the phosphor 162 can be observed.

Therefore, the observer outside the front substrate 12 observes the display of the anode of the front substrate 12 with the scattered light of the anode of the rear substrate 11 as a background.

The fluorescent substance 142 of the back substrate 11 arbitrarily combines the light emitting colors red (R), green (G), and blue (B) (at least two colors (two or more types are preferred), thereby providing a desired background color. It can be created.

FIG. 2 is a cross-sectional view of an embodiment of the anode formed on the front substrate 12, and is an enlarged view of a portion corresponding to FIG. 1B.

2A, a smoothing layer 163 made of a transparent insulating material, for example, glass, is formed on the inner surface 121 of the front substrate 12 in a flat plate shape, and an anode electrode 161 is formed on the smoothing layer 163. In order to smooth the rough surface of the inner surface 121 of the smoothing layer 163, the influence of the scattering of the emitted light of the fluorescent substance 162 becomes smaller than the case of FIG. 1B.

FIG. 2B illustrates that the anode electrode 164 is formed in a flat plate shape or a pattern shape on the inner surface 121 of the front substrate 12 by a transparent conductive material such as indium tin oxide (ITO) or the like. 164 is applied to the phosphor 162. The anode electrode 164 smoothes the rough surface of the inner surface 121 similarly to the smoothing layer 163 of FIG. 2A. Therefore, in this case, since the anode electrode 164 also functions as a smoothing layer, the structure becomes simpler than in the case of Fig. 2A.

In the above embodiment, although the patterns of the anodes of the front substrate and the back substrate are respectively seven segments and the bar shape, the patterns are not limited to these patterns and are used for conventional fluorescent display tubes such as characters, dots, and graphics. It may be another pattern.

In addition, the display of the anode of the back substrate is not only a single color display of red (R), green (G), and blue (B), or a combination of two or more colors thereof, but also a gradation (for example, Japanese patent application of the present applicant). 2000-219964) may be added, and the color may be not only a combination but also a sign of significance.

The roughening of the inner surface of the front substrate may be performed on the entire surface of the front substrate, or may be performed only on the display area.

The anode of the rear substrate may be provided on the entire surface of the rear substrate, or may be provided on all or part of the display area.

The front substrate in the above embodiment has the same function as that of a conventional neutral density filter by roughening the inner surface thereof. That is, since the front substrate of the conventional bi-planar fluorescent display tube uses a transparent glass plate, when viewed from the outside, the internal parts of the fluorescent display tube can be seen, and the metal wiring, the anode electrode, or the reflection from the phosphor Contrast falls with light, and visibility decreases. Therefore, although the neutral density filter is conventionally provided and the contrast is prevented, this invention does not need to provide the neutral density filter.

In addition, the metallic luster of wirings, anode electrodes and the like scatters on the rough surface of the front substrate, exhibits white or milky white, and exhibits a gentle white color which does not flash as a whole together with its own index white color of the phosphor at the time of non-luminescence. As a result, the biplanar fluorescent display tube of the present invention is improved in contrast and the visibility is improved.

Next, the roughening of the inner surface 121 of the front substrate 12 in the above embodiment will be described.

Since the inner surface 121 of the front substrate 12 is directly formed with wirings such as aluminum, anodes, etc., the roughness of the inner surface 121 is formed in consideration of the film thickness of the wirings, and electrical conduction such as wirings. Select the range that does not interfere with.

Fig. 4 shows the roughness of the inner surface of the glass substrate and resistance to the arithmetic mean roughness Ra of the rough surface and wiring in the case of forming an aluminum wiring or the like having a film thickness of about 1 μm on the roughened inner surface. The relationship of the rate of increase of a value is shown. When the film thicknesses of wirings and the like are the same, the higher the arithmetic mean roughness Ra of the rough surface, and therefore, the rougher the rough surface, the greater the rate of increase of the resistance value of the wiring or the like.

In this embodiment, the arithmetic mean roughness Ra of the inner surface 121 is selected to be 1000 dB or less. Appropriate roughness of the inner surface 121 varies depending on the film thickness of the wiring or the like, but for example, when the film thickness of the wiring or the like is about 1 μm, the arithmetic mean roughness Ra is selected to be 800 kPa or less, preferably 500 to 300 kPa. It is safe to do

In this embodiment, the arithmetic mean roughness Ra of the inner surface 121 is selected to be 1000 kPa or less. However, when the thickness of the wiring or the like is thickened, the arithmetic mean roughness Ra can be set to 1000 kPa or more. ). That is, the film thickness of wiring etc. is changed corresponding to arithmetic mean roughness Ra.

Although roughening of the inner surface 121 of the front substrate 12 is performed by sandblasting, chemical polishing, or the like, in the case of sandblasting, alumina having roughness # 2000 to # 600 (JIS) may be used. Preferably, alumina having roughness # 2000 to # 800 may be used.

According to the present invention, the inner surface of the front substrate of the biplanar fluorescent display tube is roughened so that the visibility of the display of the anode (front anode) of the front substrate is not impaired. The display can be used to create background effects. In other words, by roughening the inner surface of the front substrate, the intelligibility of the display of the front anode hardly decreases, but the intelligibility of the display of the back anode is degraded, and the light emission such as the bar shape or the dot shape becomes unclear in the boundary. Since it becomes difficult to do so, the whole surface becomes a uniform smooth background display. Accordingly, the present invention can create various background displays by changing the pattern of the back anode, the type of phosphor to be applied, the coating separation method, and the like, so that the expression content of the display of the front anode can be enriched, thereby making biplanar fluorescence possible. The use of the display tube can be expanded.

Moreover, in the conventional bi-planar fluorescent display tube, although the display of the back anode appears brighter to the observer outside of the front substrate, the present invention improves its viscosity by roughening the inner surface of the front substrate.

By roughening the inner surface of the front substrate of the present invention, the front substrate is also provided with the function of a conventional neutral density filter. Therefore, the contrast can be improved and the visibility can be improved without providing the same filter separately.

In addition, since the metallic luster of wiring, an anode electrode, etc. scatters on the rough surface of a front substrate, it shows white or milky white, and it shows the mild white which does not flash as a whole with the index white of the fluorescent substance at the time of non-luminescence, and this invention The visibility is improved along with the improvement of the contrast.

Claims (4)

A biplanar fluorescent display tube comprising a front substrate on which an anode electrode coated with a phosphor is formed on an inner surface, a back substrate on which an anode electrode coated on a phosphor is formed on an inner surface thereof, and a cathode disposed between both substrates, Inner surface of the front substrate is characterized in that the rough Biplanar Fluorescent Display Tube. The method of claim 1, The anode electrode formed on the front substrate is made of a transparent conductive material, characterized in that Biplanar Fluorescent Display Tube. The method of claim 1, The anode electrode formed on the front substrate is made of a non-transmissive conductive material, characterized in that it has a transparency Biplanar Fluorescent Display Tube. The method of claim 1, An anode electrode is formed in the smoothing layer which consists of a transparent insulating material formed in the inner surface of the front board | substrate. Biplanar Fluorescent Display Tube.