JPH0622922Y2 - Fluorescent tube - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention has a plurality of pixels as one light emitting section inside, and combines several to tens of thousands of pixels to form one large-sized display device. The present invention relates to a tube, and more particularly, to improvement of a control electrode group arranged inside.

[Prior art]

In recent years, at baseball fields, various stadiums, stations, and open spaces,
In order to display the images or images of the contents of the competition or various events, a large display device of several meters in length and several tens meters is used. It is difficult to form this type of display device with a single display device due to manufacturing problems or handling problems. Therefore, for example, by applying the principle of a fluorescent display tube, one fluorescent substance that emits three colors of red, blue, and green is defined as one pixel, and a plurality of fluorescent luminous tubes in which a plurality of these pixels are arranged are combined. There has been proposed a large-sized display device capable of obtaining a large screen.

3 (a) to 3 (c) show an example of a conventional fluorescent light emitting tube, FIG. 3 (a) is a partially cutaway plan view thereof, and FIG. 3 (b) is a longitudinal direction ( Fig. 3 (c) is a lateral (longitudinal) side sectional view.

In the figure, A is an envelope, which includes an anode substrate 1 made of a translucent insulating material such as a glass plate to form a display surface, side plates 2a and 2b and a back plate 3 made of a glass plate, and a low melting point frit glass. It is fixed by a sealing material 4 made of, for example, and is formed in a box shape.

Of these, the inner-color surface of the anode substrate 1 is coated with a rectangular pattern-shaped superluminescent phosphor 5a, red-emitting phosphor 5b, and blue-emitting phosphor 5c. A graphite layer 6 is formed on the inner surface of the anode substrate 1 so as to surround the phosphors 5a, 5b and 5c. Further, a thin metal back layer 7 is formed on the lower surface (on the rear plate 3 side) of the phosphors 5a, 5b, 5c and the graphite layer 6 by depositing Al or the like. And
On the lower surface of the metal back layer 7, there is disposed a separator 8 made of a metal structure and having protrusions formed so as to surround the phosphors 5a, 5b, 5c, respectively. Is forming. Also, the phosphor
Pixels 5 as one light-emission section are formed by grouping 5a, 5b, and 5c, and as shown in FIG. 3 (a), a total of eight pixels 5 are arranged regularly in two rows vertically and four columns horizontally. ing. Then, the light emitting display is observed through the anode substrate 1.

On the other hand, on the inner surface of the back plate 3, eight electrode units 9 made of a metal structure are arranged so as to face the pixels 5 and correspond to the respective pixels 5. Also, the third
As shown in FIGS. (B) and (c), the electrode units 9 are connected to each other by a metal frame 10, and inside,
A linear cathode 16 in which an oxide is deposited on a tungsten core wire, a first grid 17, and a second grid 18 are arranged.

More specifically, an insulating plate 15a made of ceramics or the like is provided at the bottom of the electrode unit 9, and the phosphors 5a, 5 are provided between the supports 14, 14 attached to the insulating plate 15a.
Three linear cathodes 16 are stretched so as to correspond to b and 5c, respectively.

In addition, insulating plates 15b and 15b are provided on both side surfaces of the linear cathode 16 in the electrode unit 9 in the stretching direction, respectively. And above the linear cathode 16, the linear cathode 16
A first grid 17 corresponding to each of them and extending in the stretching direction is arranged. The first grid 17 has a substantially semi-cylindrical portion facing the phosphors 5a, 5b, 5c, and has a large number of slits in a direction orthogonal to the extending direction of the linear cathode 16, and both ends thereof. The lower portion and the lower portion are held by insulating plates 15b, 15b and insulating plate 15a, respectively.

On the other hand, on the upper part of the electrode unit 9, each phosphor 5a, 5b, 5c is formed.
An opening is formed in correspondence with the above, and the second grid 18 having a mesh-shaped opening is attached to this opening.

Reference numeral 11 is an anode lead that is connected to the separator 8 and is used to supply electricity to the anode. Furthermore, 12 is an exhaust pipe,
After arranging various electrodes inside and assembling the envelope A, the inside of the fluorescent light emitting tube is evacuated to a high vacuum and then sealed to keep the inside in a high vacuum state. The anode lead 11
Is a structure led out from this exhaust pipe. Reference numeral 13 is a lead wire that is connected to the first grid 17 and the like and that conducts electricity to the internal electrodes.

In addition, a getter or the like is arranged inside the fluorescent light emitting tube to increase the degree of vacuum inside.

Then, a large-sized display device is formed by combining a large number of such fluorescent luminous tubes, and the linear cathode 16 is electrically heated to generate electrons emitted from the linear cathode 16 based on the display signal. It is controlled by the grid 17 and is accelerated by the second grid 18, while being selectively projected onto the anodes (phosphors 5a, 5b, 5c) to which a high voltage is applied, to obtain a desired light emission display.

[Problems to be solved by the invention]

By the way, the linear cathode 16 has support members 14 and 1 at both ends thereof.
It is the structure installed in 4. Therefore, when the linear cathode 16 is electrically heated, heat is transferred to the support 14,
At both ends of the linear cathode 16, sufficient electrons necessary for light emission cannot be emitted. Then, the electrons emitted from the linear cathode 16 impinge on the phosphors 5a, 5b, 5c with almost no bending in the stretching direction of the linear cathode 16, so that the phosphor 5
At both ends in the longitudinal direction of a, 5b, and 5c, sufficient electrons required for light emission cannot be obtained, and there is a problem in that luminance is reduced and non-light emitting portions occur at both ends.

Further, in the fluorescent light emitting tube shown in FIGS. 3 (a) to (c), one phosphor corresponds to one linear cathode, but a plurality of phosphors (for example, for one pixel) ) Or when one linear cathode faces a plurality of pixels, and when a plurality of phosphors and a plurality of linear cathodes correspond to a plurality of pixels, the direction in which the linear cathode is stretched. There is a problem that the phosphors or pixels near both ends of the are lower in brightness than other phosphors or other pixels, or non-luminous portions are generated.

[Means for solving problems]

The present invention has been made in view of the above problems,
By eliminating the decrease in brightness in the phosphors or pixels facing each other in the vicinity of both ends of the linear cathode, and eliminating the brightness variations among the pixels in the fluorescent arc tube or the local brightness variations in each phosphor, a large combination is possible. The object of the present invention is to provide a fluorescent light emitting tube with extremely high display quality with little variation in brightness when forming the display device.

In order to achieve the above-mentioned object, the configuration of the present invention has a linear cathode that emits electrons when heated by electricity, a control electrode group that accelerates and controls the electrons emitted from the cathode, and a rectangular pattern shape. And a plurality of such phosphors are disposed on the anode substrate, and the anode substrate forms a part and has an airtight envelope in which these various electrodes are disposed. In the fluorescent luminous tube to be formed, the cathode is stretched and arranged so as to extend in the longitudinal direction of the phosphor, and at least one control electrode of the control electrode group is at the center in the stretching direction of the cathode. It is formed such that both ends of the part are closer to the cathode and are parallel to the anode substrate in the direction orthogonal to the extending direction of the cathode.

[Action]

Due to the above-mentioned configuration, the electrons emitted from the cathode are diffused in the stretching direction of the cathode while passing through the control electrode group, and are necessary for light emission in the phosphor and the pixel facing the both ends of the cathode. You can get electrons.

〔Example〕

Hereinafter, the present invention will be described in detail with reference to the drawings. Since the basic structure is the same as that of the conventional fluorescent light emitting tube shown in FIGS. 3 (a) to 3 (c), the same parts are designated by the same reference numerals and the description thereof will be omitted.

1 (a) and 1 (b) are a side sectional view in the short side direction showing an embodiment of the fluorescent light emitting tube of the present invention and an external view showing the electrode unit thereof.

In the figure, A is an envelope in which the anode substrate 1, the side plate 2b, and the back plate 3 are fixed via a sealing material 4 to form a box shape. The anode substrate 1 also has three rectangular phosphors 5a, 5b, 5c which emit green, red and blue light respectively.
Are arranged, and the pixels 5 are formed by using these as a set. Further, a graphite layer 6 and a metal back layer 7 are adhered and formed on the inner surface of the anode substrate 1, and each phosphor 5a, 5b, 5c is formed.
A separator 8 having a protrusion is arranged so as to surround it.

On the other hand, on the inner surface of the back plate 3, the electrode units 21 made of a metal structure are arranged corresponding to the pixels 5, respectively. The electrode unit 21 includes the phosphors 5a, 5b, 5c of the pixel 5
Corresponding to the above, three linear cathodes 16 are stretched and arranged between the supports 14 and 14, respectively. Further, above the linear cathode 16 (on the side of the anode), a first grid 17 corresponding to each linear cathode 16 and electrically independent from each other is provided. Then, the electrons emitted from each linear cathode 16 are controlled by the first grid 17. Further, the electrode unit 21 has a first
A second grid 22 having a mesh-shaped opening is attached so as to be located between the grid 17 and the anode substrate 1. The second grid 22 has a configuration in which the linear cathode 16 is curved in a semicylindrical shape with respect to the stretching direction, and at both ends of the linear cathode 16,
The linear cathode 16 is arranged closer to the center of the linear cathode 16. Further, the electrode unit 21 includes a linear cathode 16 (each phosphor
5a, 5b, 5c) are provided with slit-shaped openings corresponding to the positions.

As described above, since the second grid 22 is curved in a semicylindrical shape with respect to the stretching direction of the linear cathode 16, the electrons emitted from the linear cathode 16 are the first After being selectively controlled by the grid, the fluorescent lenses 5a, 5b, 5c on the inner surface of the anode substrate 1 are diffused in the stretching direction of the linear cathode 16 by the electrostatic lens formed by the second grid 22, and the longitudinal corners of the phosphors 5a, 5b, 5c. Sufficient electrons necessary for light emission reach. However, electrons do not diffuse more than necessary in the short side direction of each of the phosphors 5a, 5b, 5c.

Therefore, in the longitudinal end portions of the phosphors 5a, 5b, 5c, the brightness is lower than that in the central part, or a non-light emitting portion does not occur, and there is little brightness variation in each phosphor 5a, 5b, 5c. It is possible to obtain a uniform and high-luminance light emitting display. Moreover, in the short-side direction of the phosphors 5a, 5b, 5c, electrons are not diffused more than necessary, and adjacent phosphors do not emit more light. Further, when combined to form a large-sized display device, a display device having extremely high display quality can be obtained.

[Other Examples]

FIG. 2 (a) shows another embodiment of the fluorescent light emitting tube of the present invention. Similar to the previous embodiment, the basic structure is shown in FIG.
Since it is the same as the conventional fluorescent light emitting tube shown in (a), (b) and (c), the same parts are denoted by the same reference numerals and the description thereof will be omitted.

On the inner surface of the back plate 3, an electrode unit 31 made of a metal structure is arranged corresponding to each pixel 5 composed of the phosphors 5a, 5b and 5c. In this electrode unit 31, each phosphor 5a, 5b,
Corresponding to 5c, three linear cathodes 16 are attached to the supports 14 and 14 respectively.
It is stretched between them. In the electrode unit 31, the linear cathode 16 is provided above the linear cathode 16 (on the side of the anode substrate 1).
Corresponding to each, a first grid 32, which is electrically independent of each other, is provided. The first grid 32 has a mesh-shaped or slit-shaped opening and is curved in the direction in which the linear cathode 16 is stretched, and is also curved in the direction orthogonal to the linear cathode 16, and is substantially dome-shaped. Is doing. Further, the electrode unit 31 has a second grid 18 having a mesh-shaped or slit-shaped opening at a position facing the anode substrate 1.
Is provided.

Therefore, the electrons emitted from the linear cathode 16 are also diffused in the stretching direction of the linear cathode 16 by the electrostatic lens formed by the first grid 32 as shown by the broken line, and the phosphors 5a, 5b, Sufficient electrons required for light emission can be obtained up to both ends in the longitudinal direction of 5c. In addition, electrons are not diffused more than necessary in the short side direction of the phosphors 5a, 5b, 5c.

Therefore, the luminance at the longitudinal end portions of the phosphors 5a, 5b, 5c is lower than that at the central portion, or non-luminous portions do not occur at both end portions, in each of the phosphors 5a, 5b, 5c, the respective luminance variations. It is possible to obtain a uniform and high-luminance light-emitting display. Further, in the short-side direction of the phosphors 5a, 5b, 5c, electrons are not diffused more than necessary, so that adjacent phosphors do not emit more light. Furthermore, when combined to form a large-sized display device, it is possible to obtain a display device with extremely high display quality with little variation in brightness.

In the above-mentioned two embodiments, one of the first and second grids arranged in the electrode unit is curved so that the central portion thereof protrudes toward the anode substrate side in the stretching direction of the linear cathode. Although the example is shown, both the first and second grids may be curved. Further, in the curved grid of the first and second grids, the aperture ratio of the mesh or slit is increased to change the electron transmittance as it approaches the two ends of the linear cathode in the stretching direction. The electrons can be more effectively diffused by changing the state of the electrostatic lens. Further, in the second grid, each phosphor 5a, 5b, 5c may be curved in accordance with the direction orthogonal to the extending direction of the linear cathode 16 for each pixel 5 or the pixel 5.

In addition, as shown in FIG. 2 (b), the second grid 22a is arranged so that only the both ends are on the side of the linear cathode 16 so that the cross section becomes substantially trapezoidal with respect to the stretching direction of the linear cathode 16. Even with a bent shape, the same effect as in the previous embodiment can be obtained. Also,
As shown in FIG. 2 (c), the second grid 22b is connected to the linear cathode 16
It may have a cross section or an inverted V shape with respect to the stretching direction.

In addition, the shape of the first grid or the second grid is not limited to the embodiment, such as bending both end portions in several steps so as to be close to the linear cathode. Any shape may be used as long as both ends are located closer to the cathode with respect to the central part.

On the other hand, in the above-mentioned embodiment, the fluorescent light emitting tube in which the electrode unit corresponds to each pixel and the linear cathode corresponds to the phosphor of each pixel is shown as an example, but one linear cathode corresponds to one pixel. Alternatively, the present invention can be applied to a fluorescent light emitting tube having a structure corresponding to several pixels or a structure in which a plurality of linear cathodes correspond to unspecified pixels.

〔effect〕

As described above, the fluorescent light emitting tube of the present invention is arranged so that the cathode extends in the longitudinal direction of the phosphor, and at least one control electrode of the control electrode group located between the linear cathode and the substrate is disposed. A shape in which both ends thereof are closer to the cathode with respect to the center portion in the stretching direction of the cathode, and are formed to be parallel to the anode substrate in a direction orthogonal to the stretching direction of the cathode. Is.

Therefore, the electrons emitted from the cathode are diffused in the extending direction of the cathode by the control electrode, and the decrease in the electron emission capability caused by the temperature decrease (end cool) at both ends of the cathode is compensated. Therefore, even in the vicinity of both ends of the cathode, sufficient electrons necessary for light emission are projected onto the phosphor, so that there is no decrease in brightness or non-emission of light as compared with the vicinity of the center of the cathode. Further, in the short side direction of the fluorescent substance, electrons are not diffused more than necessary, so that the adjacent fluorescent substance does not emit more light. Since the variation in luminance within each phosphor or the variation in luminance among pixels is reduced, uniform and high-luminance light-emitting display can be obtained. Further, when one large-sized display device is formed by combining the fluorescent light emitting tubes, it is possible to obtain a display device with extremely low display quality and extremely high display quality.

[Brief description of drawings]

1 (a) and 1 (b) are side cross-sectional views in a short side direction and a partially enlarged external view showing an embodiment of the fluorescent light emitting tube of the present invention, and FIG.
(a) is a side sectional view in a short side direction showing another embodiment of the fluorescent light emitting tube of the present invention, and FIGS. 2 (b) and (c) are main parts showing the other embodiment. Enlarged sectional views, FIGS. 3 (a), (b), and (c) are a partially cutaway plan view showing an example of a conventional fluorescent light emitting tube, and side sectional views in the long side direction and the short side direction. 1 ... Anode substrate, 5a, 5b, 5c ... Phosphor 9,21,31 ... Electrode unit (control electrode group) 14 ... Support, 16 ... Linear cathode (cathode) 17, 32 ... 1 grid (control electrode) 18, 22 ... 2nd grid (control electrode) A ... envelope, 22a, 22b ... 2nd grid (control electrode)

Claims (1)

[Scope of utility model registration request] 1. A linear cathode that emits electrons when electrically heated, a control electrode group that accelerates and controls the electrons emitted from the cathode, and a large number of phosphors having a rectangular pattern shape. In a fluorescent display tube having an anode substrate and an airtight envelope in which the anode substrate forms a part and in which various electrodes are arranged, and a plurality of units are combined to form one display device, the cathode is used. Is arranged so as to extend in the longitudinal direction of the phosphor, and at least one control electrode of the control electrode group has a cathode at both ends with respect to a center portion in the extension direction of the cathode. A fluorescent light emitting tube characterized by being formed so as to be parallel to the anode substrate in a shape close to, and in a direction orthogonal to the extending direction of the cathode.