JPS60253145A - Color fluorescent light emitting tube - Google Patents

Abstract

PURPOSE:To prevent occurence of electric discharge even if high speed electron beam is used, by placing a shield plate between the negative electrode filament and the side plate. CONSTITUTION:A shield plate 38 is placed between a negative electrode filament 22, a control grid 23, a screen grid 28 and a side plate 17, so as to screen the side walls of the formers from the latter. The high speed electron beam released from the negative electrode filament 22 is controlled by a control grid 23 and uniformly collides with the light emitting cells 12 to make the light emitting cells emit light. During this time, a part of released electrons heads towards the side plate 17 from the filament 22, control grid 23 and side of screen grid 28. However, it is shielded by the shield plate 38, and thus does not collide with the side plate 17. As a result, the generation of electric discharge between the negative electrode filament and the side plate can be prevented. As the shield plate 38 is an electrically conducting material and is maintained at the same potential as the screen grid 28, electric discharge between the shield plate and the negative electrode filament is never generated.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a color fluorescent light emitting device comprising a plurality of light emitting cells, a shade filament stretched across them, and a control grid and a shielding grid provided between the cells. It relates to tubes, and in particular to color fluorescent light emitting tubes that prevent high-speed electron beams emitted from a cathode filament from leaking from the longitudinal side surfaces of the filament and impinging on the side plates of the light emitting tube container. It is.

Conventionally, a color fluorescent light emitting tube as shown in FIG. 1 has been proposed as a pixel light emitting tube for constructing a large display or the like. In the figure, a plurality of light emitting cells 1 are connected to a diffusion plate 2
The light-emitting center is divided by the north,
For example, red, green, and blue phosphors are deposited. A cathode filament 3 is stretched above the light emitting cell 1 so as to face it, and a picture grid 4 and a continuous grid 5 are provided between the cathode filament 3 and the light emitting cell 1. ing. Note that 6 is a side plate. In this configuration, the electrons emitted from the cathode 3 are prevented from passing through by the control grid 4, so that they selectively pass through the control grid 4 only in the area where the light emitting cell 1 that should emit light belongs. After passing through the shielding grid 5, the electrons uniformly impinge on the entire surface of the light-emitting cell 1 due to the diffusion effect of the diffusion plate 2, and the light-emitting cell 1
It emits light.

Incidentally, the uses of color fluorescent light emitting tubes as described above have become more diverse in recent years, and their use as pixels in special doll displays, typically ultra-large color televisions, has come to be seen as promising.

However, in color fluorescent light emitting tubes used as pixels in large color televisions, the anode is set at 10 KV due to the need to increase the light emitting area and increase the brightness.
It was necessary to maintain the voltage at a reasonably high voltage and to bombard the light emitting cell with electrons at high speed.

However, in the prior art described above, the electrons emitted from the cathode filament 3 leak from the longitudinal sides of the cathode filament 3, the control grid 4, and the shielding grid 5, and reach the side plate 6 of the arc tube container. If there is a collision phenomenon and the electrons are at high speed as described above, secondary electron emission will occur from the side plate, and since the plate is an insulator, it will be charged to a positive high voltage.

The cathode filament is usually at ground voltage, and both (
Because the distance between the filament and the side plate is close, there is a drawback that discharge occurs between the cathode filament and the side plate through residual gas, resulting in abnormally high temperature and damaging the cathode filament. Ta. In addition, cathode filament coating materials ((Ba, Sr,
When Ba evaporates from Ca(J)Ha) and adheres to the side plate, the above-mentioned discharge problem becomes extremely serious.

The object of the present invention is to solve the problem of IC between the cathode filament and the side plate due to the structural limitations of the color fluorescent light emitting tube based on the prior art, and to provide a structure in which a shield plate is interposed between the cathode filament and the side plate. By doing so, it is an object of the present invention to provide an excellent color fluorescent light emitting tube that eliminates the above-mentioned drawbacks and does not cause a discharge phenomenon even when using a high-speed electron beam.

The configuration of the present invention in accordance with the above object includes a plurality of light emitting cells,
In a color fluorescent light emitting tube consisting of a cathode filament stretched across the cathode filament, and a lid and a shielding grid provided between them, the longitudinal sides of the cathode filament, the control grid and the shielding grid are closed. A shield plate is provided to block the high-speed electron beam emitted from the cathode filament,
The purpose of this is to prevent collisions with the side plates of the arc tube container.

Next, an embodiment of the present invention will be described below based on the five drawings from FIG. 2 onwards.

In FIG. 2, an anode 11 made of a conductive film before graphite is formed in a frame shape on a display plate 10, and a plurality of different types of phosphors, for example, a red-emitting phosphor (Y2O2
S:Eu), green-emitting phosphor (ZnS: CuA/
), a 7'J color emitting phosphor (ZnS:Ag) is deposited, a lacquer interlayer film is applied thereon, and a metal back consisting of an A/evaporation film is further deposited to emit light. A cell 12 is configured.

A diffuser plate frame 13 is placed on the display panel 10'', and an electrical 0.J connection is made to the frame-shaped anode j1.

The diffusion plate frame 13 is provided with a plurality of diffusion plates 14, and as clearly shown in FIG.
It is located between the two and separates them from each other. Reference numeral 15 indicates an anode lead wire, and reference numeral 16 indicates a mounting pin, which is clamped and held between the display panel F10 and the side plate 17, thereby fixing the diffuser plate frame 13.

As shown on the left side of FIG. 2, a pair of cathode supports 21 are attached to the lower surface of the lead frame 20 by spot melting or the like. A cathode filament 22 is stretched at opposing positions.

A control grid 23 having an arcuate cross section is attached to the 71j aj 'J-de frame 20 so as to cover the cathode filament 22 .

On the other hand, as shown on the right side of Fig. 2, the grid holder 2
A window 27 for a shielding grid is formed in the flat plate portion 26 of No. 5, and a J! ! !
The glyph grid 28 is attached via the attachment portion 29 by spot welding. A shielding body 30 is provided on both side edges of the mounting portion 29 of the shielding grid 28 to protrude downward by bending. Further, an opening 32 is formed in the flat plate portion 26 of the grid holder 25, and a getter device 33 is attached above the opening 32. At both edges of the window 27 of the grid holder 25, partitions 37 are erected by cutting and raising them.

Further, shield plates 38 are provided at both ends of the flat plate portion 26 of the grid holder 25.
8 includes an upper portion 38a projecting upward from the flat plate portion 26, and an upper portion 38a projecting downward from the flat plate portion 26, and the shielding grid 28a projecting downward from the flat plate portion 26.
As shown in FIG. 4, when assembled, the upper part 38a partially extends to the side surface of the filament 22 and shields it. The arcuate lower portion 38b closes the open side of the shielding grid 28.

The grid holder 25 to which the shielding grid 28 is attached is attached to the lead frame 20 by the attachment part 39, and the lead frame 20 is attached to the side plate 17.
and the back plate 40. At this time, as shown in FIG. 3, the shielding lid 28 is positioned so as to cover the control grid 23 concentrically, and each light emitting cell 1
Facing 2.

Also, as shown in FIG. 4 and described above, the shield plate 38
is interposed between the cathode filament 22, the control grid 23, the shielding grid 28, and the side plate 17 to shield the side surface of the former from the latter.

The display plate 10, the side plate 17, and the back plate 40 form an arc tube container 41.

In the above configuration, a high Id voltage of about 10 t (V) is applied to the light emitting cell 12 forming the anode f4, a voltage of +30 V CW degree is applied to the shielding grid 28, and a voltage of +30 V CW is applied to the control grid 23. A voltage of about ~3 V is selectively applied, and the cathode filament 22 is maintained at approximately the ground position.The high-speed electron beam emitted from the cathode filament 22 is controlled by the control grid 23. However, only in the area where the light-emitting cells 12 to emit light belong, after passing through the control grid 23, the light is further passed through the shielding grid 28 toward the light-emitting cells 12, and further directed toward the periphery by the diffusion plate 4. In response, the light emitting cells 121 are uniformly bombarded with light, causing the light emitting cells 12 to emit light.

During this time, some of the electrons emitted from the cathode filament 22 travel from the filament 22, the control grid 23, and the side surface of the shielding grid 28 toward the side plate 17, but are shielded by the shield plate 38 and There is no possibility of collision with the plate 17. In addition, the shield plate 3
Reference numeral 8 denotes a conductor provided in the grid holder 25, and it is always kept at the same potential as the grid 28, so even if electrons strike here, the potential will not increase. There isn't. Therefore, the side plate 1 which is an insulator
Unlike case 7, no discharge occurs between the cathode filament 22 and the cathode filament 22.

As described above, in this invention, high-speed electron beams emitted from a cathode filament are selectively impinged on M and f'i number of light-emitting cells through a control grid and a shielding grid to cause them to emit light. In the color fluorescent light emitting tube, shield plates are provided on both sides of the grid holder that supports the shielding grid, and the sides of the cathode filament, the control grid, and the shielding grid are closed, and these are shielded from the side plates, so that the cathode filament can be protected from the cathode filament. Even if some of the emitted electrons head toward the side plate from the side of the filament, control grid, or shielding grid, their progress is blocked by the shield plate and they do not hit the side plate, so the cathode filament It is possible to prevent a visual discharge from occurring between the side plate and the side plate.

The shield plate is conductive and is always kept at the same potential as the shield grid, so even if electrons hit the shield plate, a discharge will occur between it and the cathode filament. Never.

[Brief explanation of drawings]

Figure 1 is an explanatory diagram of the principle of a conventional color fluorescent light emitting tube.
Figures (Al is a perspective view, Figure 1 is a sectional view, Figures 2 and below show the configuration of an embodiment of this invention, Figure 2 is an exploded perspective view,
FIG. 3 is a longitudinal cross-sectional view, and FIG. 4 is a cross-sectional view. 10... Display plate 12... Light emitting plate 13... Diffusion plate frame 14... Diffusion plate 17... Side plate 22... ... Cathode filament 23 ... Control grid 25 ... Grid holder 28 ... Shielding grid 38 ... Shield tentative figure 1 (A) (8) \ \ Figure 2 1'' Figure 3 Figure 4

Claims (1)

[Claims] A plurality of light emitting cells 12 that each emit light in a different color due to the impact of electrons, a cathode filament 22 facing each other above the light emitting cells, and a control grid 23 and a shielding grid provided between the cathode filament colored light emitting cells. 28, in which the shielding grid 28
Shield plates 38 are provided on both side edges of the grid holder 25 that supports the cathode filament 22, the longitudinal sides of the control grid 23 and the shielding grid 28, and the side plates 17 of the arc tube container 41. A color fluorescent light emitting tube characterized by being provided with.