JPH0582056A - Flat plate type cathode-ray tube display device - Google Patents

Abstract

PURPOSE:To contract an electron beam precisely by eliminating ooze and spread, of the electron beam having passed the first deflection electrode and the first shield electrode with the second deflection electrode and the second shield electrode having openings. CONSTITUTION:The electron beam emitted by a linear cathode 4 having passed the first deflection electrode 8 and the first shield electrode 9 having a plurality of openings 10 is redeflected by the second deflection electrode 11. At the post- stage of this electrode 11, the second shield electrode 2 is furnished which is equipped with a plurality of openings 15 to eliminate ooze and spread of electron beam due to aberration on the basis of the initial speed distribution of the electron beam, and thereby the electron beam dia. on a screen can be contracted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flat panel cathode ray tube display device for displaying characters and graphics, and more particularly to improvement of electrode means for controlling electron beam landing such as color selection. ..

[0002]

2. Description of the Related Art In recent years, flat panel cathode ray tube display devices have been actively developed. Most of these emit an electron beam from an electron source formed in a plane or line shape, and the electron beam is controlled with high precision by a plurality of electrodes provided three-dimensionally between the electron source and the screen. The image is deflected, and then the electron beam is projected onto the screen to display an arbitrary image.

By the way, the present applicant has previously proposed a flat panel cathode ray tube display device 16 having a structure shown in FIG. That is, the flat-panel cathode-ray tube display device 16 shown in the figure is arranged in a direction orthogonal to the linear cathodes 4 and a plurality of linear cathodes 4 stretched and stretched substantially parallel to each other with a predetermined interval. The rear electrode 5, the extraction electrodes 7 provided in the same number as the linear cathodes 4, the first deflection electrode 8 provided so as to sandwich each linear cathode 4, and the subsequent stage of the first deflection electrode 8. The shield electrode 9 arranged in a plane and the second deflection electrode 11 provided so as to sandwich the opening 10 provided in the shield electrode 9 therebetween.
And the screen 12 having an anode integrated with the phosphor are housed in the envelope 17 shown in FIG. The back electrode 5 is formed in a stripe shape on the insulating back plate 13, and the screen 12 is formed in a plane shape on the front plate 14 made of glass or the like.

Next, the above-mentioned components and their functions will be described.

The linear cathode 4 is, for example, a direct heating type in which a tungsten thin wire having a diameter of several tens of micrometers is directly coated with an electron emissive oxide such as (Br, Sr, Ca) O, or a heat resistant insulation such as alumina. It is formed from any of the indirectly heated type in which an electron emissive oxide such as a nickel sleeve is coated on a material-coated tungsten thin wire heater line. In the case of direct heating type, directly energize the tungsten thin wire,
Also, in the case of the indirectly heated type, by energizing the heater wire,
The electron emissive oxide has an electron emissive temperature of 600 to 80
It is heated to 0 ° C. to emit electrons from each surface.

The back electrode 5 is a flat panel cathode ray tube display device 1.
The horizontal image degree of 6 is formed in the same number of divisions, and the electron beam deflected in the y direction with respect to the screen 12 is x.
It is for controlling the direction and applying a voltage for data input.

The extraction electrode 7 is formed of a thin metal plate having a plurality of apertures 6 for passing electron beams or a laminate of a plurality of the metal thin plates.
Are arranged so as to correspond to the linear cathodes 4. Further, at the time of emitting the electron beam, a voltage that is relatively more positive than the voltage applied to the linear cathode 4 is applied, and the electron beam is extracted from the linear cathode 4 and the electron beam is directed to the screen 12. Deflection in the y direction.

The first deflecting electrode 8 is formed of a metal thin plate or an insulating plate to which a metal thin plate or a thin film is fixed, and is arranged so as to sandwich the linear cathode 4. At the time of emitting the electron beam, a stepwise or sawtooth wave voltage having different polarities with respect to a certain bias level is applied to deflect the electron beam toward the screen 12 at a wide angle.

The shield electrode 9 has a plurality of apertures 10 for passing electron beams, and has a thickness of, for example, 0.05.
〜0.15mm 426 alloy (Ni: 42%, Cr: 6%,
The balance: Fe) or the like is formed from a thin metal plate, and a DC voltage of about 3 to 5 kV is applied at the time of emission of the electron beam, and the low voltage side is arranged closer to the linear cathode 4 than the shield electrode 9. Electrodes (first deflection electrode 8 and extraction electrode 7
Etc. Is electrically shielded from the high voltage anode of the screen 12 to which a voltage of 10 to 15 kV is applied,
The electron beam deflected by the first deflection electrode 8 is opened 1
By passing 0, the irregular portion is removed, and it further serves to focus the electron beam toward the screen 12.

The second deflection electrode 11 has a diameter of 0.1 to 0.1.
A stainless wire of about 0.2 mm or a thickness of 0.1 to 0.
It is formed by etching a stainless steel plate of about 15 mm into a blind shape, and is fixed by sealing with a low melting point solder glass to the shield electrode 9 so as to sandwich the opening 10, or is formed so as to surround the shield electrode 9 on four sides. It is fixed to a rigid frame-shaped frame (not shown) by welding or low melting point solder glass. At the time of electron emission, a stepwise or sawtooth wave voltage having a peak value of several kV is applied to land the electron beam uniformized by the shield electrode 9 on a predetermined position of the screen 12.

The screen 12 is planarly provided on a front plate 14 made of a transparent insulating material such as glass. When the electron beam is emitted, a high voltage of several to several tens kV is applied to the anode to accelerate the electron beam. , To excite collisions and to emit light.

As shown in FIG. 5, these constituent members are precisely assembled after being positioned at predetermined positions, and an envelope formed by sealing a front plate 14 and a rear plate 13 having side walls. It is stored in 17. Then, the envelope 17
The inside is evacuated hot by an exhaust system (not shown), and in order to keep the inside of the envelope 17 at a high vacuum, the getter 18 provided near the side wall is flushed to remove impurities in the envelope 17. Is absorbed. Where the getter 18
Is generally a Ba getter. This getter 1
In No. 8, a mixture of BaAl ₄ and Ni powder that is stable in the atmosphere is heated at a high frequency to form NiAl ₄ and unstable BaAl _4, and the getter action is performed by utilizing the high reactivity of Ba. .. By the way, since Ba has a low work function and easily emits electrons,
If the Ba vapor deposition film produced when the No. 8 is flashed adheres to the electrode end portions having the potential difference, discharge occurs between the electrodes. Therefore, the Ba vapor deposition film must be attached only in the gap between each electrode and the side wall. In FIG. 5, the same parts as those in FIG. 4 are designated by the same reference numerals.

[0013]

However, the above-mentioned flat panel cathode ray tube display device 16 has the following problems. That is, in this flat-panel cathode-ray tube display device 16, between the linear cathode 4 and the extraction electrode 7, between the extraction electrode 7 and the first deflection electrode 8, between the first deflection electrode 8 and the shield electrode 9, and between the shield electrode 9 Since the electro-optical lens system generated between the screen and the screen 12 is a focusing system, chromatic aberration becomes large due to variations in the initial velocity of electrons,
As a result, there arises a problem that the diameter of the electron beam on the screen 12 cannot be reduced.

Further, as described above, the flash of the getter 18 is carried out while being controlled so that the Ba vapor deposition film does not adhere to the electrode end portion, but the getter material (BaAl _{4 in} this example) has essentially a large adsorption force. Since it is a powder, it absorbs and occludes water, oxygen, carbon dioxide, an organic binder, etc. during the manufacturing process, and these oxygen, carbon dioxide, etc. evaporate at the same time as Ba when the getter 18 is flushed later. Then, the Ba particles are scattered and the screen 1
2 also spreads in a direction parallel to 2 and a part of it also adheres to the second deflecting electrode 11 having a potential difference of 5 kV or more between the second deflecting electrode 11 and the screen 12. A discharge has occurred between them. This phenomenon is particularly remarkable in the case of an electrode formed by etching a thin metal plate. Particularly, in the etching electrode, the peripheral edge portion of the etching opening has an acute angle, and electric field concentration easily occurs in that portion.

[0015]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is not to cause such troubles but to accurately reduce the electron beam diameter and to generate discharge between electrodes. An object of the present invention is to provide a flat panel cathode ray tube display device that does not have such a problem.

[0016]

The structure of the present invention for achieving the above object comprises a linear cathode for emitting an electron beam,
It is composed of first and second deflection electrodes for deflecting the electron beam, a planar electrode having a plurality of apertures, and a screen provided with an anode integrated with a phosphor, and the first deflection electrode The deflected electron beam is passed through the aperture of the planar electrode to which a constant voltage lower than the voltage applied to the anode is applied, and then is deflected again by the second deflection electrode to display an image. In the flat panel cathode-ray tube display device to be performed, a second planar electrode having a plurality of openings is provided after the second deflection electrode.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail with reference to FIG.

The feature of the present invention is that a second planar electrode having a plurality of apertures 15 in the subsequent stage of the second deflecting electrode 11 (referred to as a second shield electrode 2; the same applies in the detailed description below). Is provided. That is, two shield electrodes (referred to as the first shield electrode 9 and the second shield electrode 2) to which substantially equal voltages are applied are configured, and the second deflection electrode 11 is the first shield electrode.
It is arranged between the shield electrode 9 and the second shield electrode 2.

FIG. 1 is a perspective view showing an electrode structure of a flat panel cathode-ray tube display device 1 according to the present invention. Other than the addition of the second shield electrode 2, the other electrode arrangement and the function of each electrode are shown in FIG. This is the same as the conventional example shown by 4 and 5. Therefore, the same parts are denoted by the same reference numerals.

That is, the flat panel cathode ray tube display device 1 of the present invention.
Is a plurality of linear cathodes 4 stretched and stretched substantially parallel to each other with a predetermined interval, a back electrode 5 arranged in a direction orthogonal to the linear cathodes 4, and the same number as the linear cathodes 4. A plurality of apertures 6 which are provided in the book and through which an electron beam passes
And a first deflection electrode 8 provided so as to sandwich each linear cathode 4, and a first deflection electrode 8
The first shield electrode 9 arranged in a plane at a position close to
(Indicated as a shield electrode 9 in FIG. 4), a second deflecting electrode 11 provided so as to sandwich the opening 10 provided in the first shield electrode 9, and a second deflecting electrode 11. A screen 12 including a second shield electrode 2 provided at a subsequent stage and having a plurality of openings 15 and an anode integrated with a phosphor.
And are housed in the envelope 17. The back electrode 5 is formed in a stripe shape on the insulating back plate 13, and the screen 12 is formed in a plane shape on the front plate 14 made of glass or the like.

As shown in FIG. 2, the second shield electrode 2 is made of, for example, a 426 alloy (N alloy having a thickness of about 0.05 to 0.15 mm).
i: 42%, Cr: 6%, balance: Fe) and the like, which is a planar thin metal plate provided with openings 15 having a diameter of 0.2 to 0.5 mm by a known etching method. A plurality of apertures 15 are provided in the X and Y directions in the drawing, and in the X direction, the second deflecting electrode 11 allows each color in the one-pixel trip in which the phosphors are painted in three colors. It is provided so as to excite and emit light in a time division manner.

The second shield electrode 2 and the first shield electrode 9 are spaced apart from each other by about 2 to 5 mm, and the second deflecting electrode 11 is provided.
Is provided in the middle of both shield electrodes so as to sandwich the openings 10 and 15, respectively. Further, both shield electrodes are commonly connected and a voltage V _{1 of} several kV is applied thereto, and every other second deflection electrode 11 is commonly connected and the voltage V ₂ from the deflection electrode drive circuit 3 gradually increases or decreases. , V ₃ is applied. Incidentally, the voltage V _2, V ₃ in which periodic voltage superimposed on the DC voltage, the center voltage V ₁ + 1 to 2 kV about, or is set to about V ₁ -1~2kV.

The electron beam scanning of the flat panel cathode ray tube display device 1 will be described below with reference to FIG. Incidentally, FIG. 3 shows a case where the central linear cathode 4 emits an electron beam.

First, an electron beam A is extracted from the linear cathode 4 by applying a voltage, which is relatively positive to the voltage applied to the linear cathode 4, to the extraction electrode 7, and at the same time, the electron is extracted by the extraction electrode 7. The beam A is focused in the direction perpendicular to the paper surface. Then, the focused electron beam A is formed on the screen 12 by the first deflection electrode 8 to which a gradually increasing, stepping, or sawtooth voltage having different polarities with respect to a certain bias level is applied. Area (S1
~ S4, not shown in FIG. See FIG. ) Towards a wide angle.

Further, an electron beam A containing a wide-angle deflected aberration is passed through an opening 10 provided in the first shield electrode 9 to remove and homogenize a portion which has a shape mismatch. The light is deflected by the potential difference between the screen 12 and the second deflection electrode 11 and then focused again by the second shield electrode 2. After that, the focused electron beam A is applied to the screen 1
An arbitrary image is displayed by precisely landing (projecting) on a phosphor (not shown) provided in 2.

A flat panel cathode ray tube display device 1 having the above-mentioned structure.
The electro-optical lens system of FIG.
A focusing lens system between the extraction electrode 7 and the first deflection electrode 8, between the first shield electrode 9 and the second deflection electrode 11, and between the second shield electrode 2 and the screen 12, , A divergent lens system is generated between the first deflecting electrode 8 and the first shield electrode 9 and between the second deflecting electrode 11 and the second shield electrode 2, so that the initial velocity distribution of the electron beam is used. The spread of the electron beam due to the drop aberration is eliminated, and as a result, the diameter of the electron beam on the screen 12 can be accurately reduced, and the color mixing phenomenon can be significantly reduced.

The discharge between the electrodes occurred between the second deflecting electrode 11 and the screen 12 where the potential difference was 5 kV or more, but the Ba vapor deposition film flashed from the getter 18 was the first shielding electrode 9. Of the first shield electrode 2 and the second deflecting electrode 11, and when the second shield electrode 2 passes through the opening 15, it adheres to the end of the opening 15 but faces the screen 12. Since the second shield electrode 2 is basically formed in a planar shape, the electric field does not concentrate at one point of the second shield electrode 2, and the discharge between the shield electrode 2 and the screen 12 does not occur.

Although the deflection directions of the electron beam by the first deflection electrode 8 and the second deflection electrode 11 are the same in this embodiment, the deflection direction of the electron beam is limited to this embodiment. For example, the first deflection electrode 8 deflects an electron beam scanned in a direction orthogonal to the linear cathode 4,
The electron beam scanned in the longitudinal direction of the linear cathode 4 may be deflected by the second deflection electrode 11.

[0029]

According to the flat-panel cathode-ray tube display device of the present invention, since the second shield electrode having a plurality of apertures is provided at the subsequent stage of the second deflection electrode, the initial velocity distribution of the electron beam is obtained. The spread of the electron beam due to the aberration can be eliminated, and as a result, the diameter of the electron beam on the screen can be narrowed. Further, since the electrode facing the screen is formed in a planar shape, even if the getter material is attached to this electrode, the electric field is not concentrated at one point on the electrode, and the discharge between the electrodes does not occur.

[Brief description of drawings]

FIG. 1 is an exploded perspective view showing an electrode configuration of a flat panel cathode ray tube display device of the present invention.

FIG. 2 is an enlarged view of a main part of FIG.

FIG. 3 is a plan view of FIG.

FIG. 4 is an exploded perspective view showing an electrode configuration of a conventional flat panel cathode ray tube display device.

FIG. 5 is a front view of a conventional flat panel cathode ray tube display device.

[Explanation of symbols]

 1 Flat-Plate Cathode Ray Tube Display Device 2 Second Shielding Electrode 3 Deflection Electrode Driving Circuit 4 Linear Cathode 5 Back Electrode 6 Opening Hole 7 Extracting Electrode 8 First Deflection Electrode 9 First Shielding Electrode 10 Opening Hole 11 Second Deflection electrode 12 Screen 13 Back plate 14 Front plate 15 Open hole

Claims (1)

[Claims] 1. A linear cathode that emits an electron beam, first and second deflection electrodes that deflect the electron beam, a planar electrode having a plurality of apertures, and an anode integrated with a phosphor. After passing the electron beam deflected by the first deflection electrode through the aperture of the planar electrode to which a constant voltage lower than the voltage applied to the anode is applied, In the flat-panel cathode-ray tube display device that performs image display by deflecting again with the second deflection electrode, a second planar electrode having a plurality of apertures is provided after the second deflection electrode. A flat panel cathode ray tube display device characterized by the above.