KR20040070907A - A Manufacturing Methode of Electric Gun's Cathode For CRT - Google Patents

Abstract

PURPOSE: A method is provided to prevent an Ekco dispersion caused due to changes of thickness of electron emitting material layer by permitting the electron emitting material layer to have a uniform density. CONSTITUTION: A method comprises a step of fixing a cathode structure of an electron gun in a pair of main chucks(201) having predetermined shapes; a step of attaching a supporting chuck(201a) to the main chucks; a step of charging a uniform electrostatic charge on the base metal of the cathode structure; and a step of attaching an electron emitting material which is charged by the electrostatic charge onto the base metal charged by the electrostatic charge.

Description

A manufacturing method of electron gun for cathode ray tube {A Manufacturing Methode of Electric Gun's Cathode For CRT}

The present invention relates to a method for manufacturing a cathode of an electron gun for a cathode ray tube, and more particularly, to a method for manufacturing a cathode of an electron gun used to insert a neck portion of a cathode ray tube to emit hot electrons to emit a fluorescent film on an inner surface of a panel.

In general, the electron gun used in the cathode ray tube includes three independent cathodes 3 as shown in FIG. 1, a first electrode 4 spaced apart from the cathode by a predetermined distance, and a predetermined distance from the first electrode. The BSC 11 is attached to the second electrode 5, the third electrode 6, the fourth electrode 7, the fifth electrode 8, the sixth electrode 9, and the upper portion arranged in the In the order of the shield cup 10, the electrodes are supplied with different voltages to obtain a constant current value so that the cutoff voltage is the same.

The electron gun emits electrons from the stem pin 1 by a heater 2 embedded in the cathode 3, and the emitted electrons are controlled by the first electrode 4, which is a control electrode. The electron beam 13 is accelerated by the second electrode 5 which is an acceleration electrode.

The accelerated electron beam is focused on the third electrode 6, the fourth electrode 7, and the fifth electrode forming the shear focusing lens, and passes through the sixth electrode 9, and the electron beam passes through the shadow mask 14. Passing through the hole of the impingement to the fluorescent surface 15 to emit light.

A reference yoke 12 shown in FIG. 1 is a deflection yoke mounted outside the electron gun and serves to deflect the electron beam 14 emitted from the electron gun to the entire screen 15.

2 shows an assembled state of the cathode and the first electrode 80 inside the electron gun.

As shown in FIG. 2, in the cathode structure of the electron gun, an electron emitting material layer 20 for emitting electrons and a cap 40 for supporting the electron emitting material layer are formed under the electron emitting material layer.

And the heater 30 for heating the electrospinning material, the sleeve 50 for transferring the heat energy generated from the heater to the cap wraps the outside to protect the heater, the holder 60 for supporting the sleeve The holder is the cathode support tube 70 and the bottom portion is welded to support the cathode.

Looking at the operation principle of the electron gun cathode formed as described above are as follows.

First, when heat is applied to the heater 30, the heat is absorbed and transferred to the cap 40 from the sleeve 50 surrounding and protecting the heater, and the heat energy transferred to the cap is transferred to the electron-emitting material.

The electron emitting material emits electrons by the thermal energy to strike the fluorescent film formed on the inner surface of the panel.

In general, the electron gun cathode formed as described above is manufactured as follows.

3A is a cross-sectional view illustrating a shape in which the electron gun cathode assembly 103 is fixed by the chuck 100, and FIG. 3B is a perspective view illustrating a process of spraying the emitter suspension 102 on the fixed cathode assembly. .

As shown, conventionally, the electron gun cathode assembly is first fixed to a pair of chucks in order to spray an emitter suspension, which is an electron emitter, on the electron gun cathode.

Thereafter, the emitter suspension 102 is sprayed on the cathode assembly by spraying the emitter suspension 102 on the cathode assembly while reciprocating the interior with a drying at a temperature of about 100 ° C. to form a layer of electron emission material 20 having a predetermined thickness. Let's do it.

In general, the chuck uses a material having high thermal conductivity because the chuck forms a layer of electron emitting material on the cathode assembly while heating.

However, the electron-emitting material layer formed by the above method has a non-uniform distribution of the surface of the emitter material and ultimately leads to a deterioration of the moire properties in the cathode ray tube.

In addition, when the thermal energy is received from the heater during the high temperature process and cathode ray tube operation of the CRT manufacturing process according to the density variation of the electron radiating material layer, the electron radiating material layer is reduced to reduce the cutoff voltage, resulting in uneven cutoff voltage.

Accordingly, the present invention is to solve the problems described above, by using a dry electrophotographic electron-emitting material layer of the electron-emitting material layer having a uniform density, the Ikeshi (Ekco) dispersion by the thickness change of the electron-emitting material layer It is an object of the present invention to provide a method for producing a cathode of an electron gun for cathode ray tubes, which can reduce the occurrence and improve the image quality and the cutoff drift characteristic of the cathode ray tube.

1 is a structural diagram of a typical cathode ray tube and electron gun

2 is a view illustrating an assembled state of a cathode and a first electrode inside the electron gun;

Figure 3a and 3b is a view showing a conventional electron gun cathode manufacturing method.

Figure 4a and 4b is a view showing a electron gun cathode manufacturing method according to the present invention.

*** Explanation of symbols for the main parts of the drawing ***

20: electrospinning material layer 30: heater

40: cap 50: sleeve

60: holder 70: cathode support tube

80: first electrode 201: main chuck

201a: Supporting Chuck 202: Hole

203 emitter material

The technical means of the present invention for achieving this object is a method for producing a layer of electron-emitting material on the cathode structure of the electron gun inserted into the cathode ray tube neck portion, a pair of chuck having a certain shape of the electron gun A fixing step of fixing a negative electrode structure, a charging step of charging a uniform electrostatic charge on top of the negative electrode structure base metal, and attaching a predetermined electrospinning material charged with static electricity to the base metal charged with the electrostatic charge. It is characterized by.

Hereinafter, with reference to the accompanying drawings, an embodiment of the present invention according to the manufacturing method will be described.

4A and 4B illustrate a process of forming a cathode of an electron gun for a cathode ray tube according to the present invention.

As shown in FIG. 4A, first, a cathode structure (not shown) of an electron gun is inserted into and fixed inside a pair of main chucks 201 having a predetermined shape.

The material of the main chuck is a metal, which is a conductor, and a hole 202 is formed to apply an emitter material on the base metal of the cathode structure to form an electron emitting material layer.

And it is charged by using the corona discharge device 203 to have a uniform electrostatic charge on the base metal of the negative electrode structure.

Thereafter, the emitter material 204 is sprayed onto the base metal charged with the electrostatic charge by using the spray gun 200 to form the electron emission material layer 20 having a predetermined thickness.

Preferably, the emitter material is sprayed by a dry electrophotographic method to form an electron emitting material layer.

Preferably, as shown in FIG. 4B, the cathode structure of the electron gun is fixed inside the main chuck 201, and then the supporting chuck 201a having the same structure is attached.

The auxiliary chuck preferably uses a non-conductive plastic material.

This is because when the auxiliary chuck is a conductor of metal material, the entire chucks 201 and 201a are charged by the corona discharge, so that the electron emission material layer is formed in a non-uniform distribution on the surface of the base metal.

In addition, the electron emitting material layer preferably has a layer composed of at least two materials of barium carbonate, strontium carbonate, calcium carbonate.

As described above, after the electrospinning material is attached by a dry electrophotographic method, a subsequent process may obtain an anode which may facilitate electron emission through an activation process which is a general process.

Therefore, the electrospinning material layer formed by the above method can reduce the Ekco scattering compared to the cathode formed by the conventional spray method, and has a uniform density on the top surface, thereby improving the moire cutoff drift characteristics in the cathode ray tube. You can.

As such, those skilled in the art will appreciate that the present invention can be implemented in other specific forms without changing the technical spirit or essential features thereof. Therefore, the above-described embodiments are to be understood as illustrative and not restrictive in all respects, and the scope of the present invention is indicated by the appended claims rather than the foregoing description, and the meaning and scope of the claims and All changes or modifications derived from the equivalent concept should be interpreted as being included in the scope of the present invention.

The present invention is a dry electrophotographic to have a uniform density of the electron emitting material layer of the electron gun has a uniform density to reduce the occurrence of Ikeshi (Ekco) dispersion by the thickness change of the electron emitting material layer, the quality of the cathode ray tube and There is an effect that can improve the cutoff drift characteristics.

Claims (5)

In the method for producing an electron-emitting material layer on top of the cathode structure of the electron gun inserted into the cathode ray tube neck portion, A fixing step of fixing the cathode structure of the electron gun to a pair of chucks having a predetermined shape, a charging step of charging a uniform electrostatic charge on top of the cathode structure base metal, and a static charge to the base metal charged with the static charge Electron gun cathode manufacturing method for an electrophotographic cathode ray tube comprising the step of attaching a predetermined electrospinning material. The method of claim 1, After fixing the cathode structure of the electron gun to the chuck, the electron gun cathode manufacturing method for an electrophotographic cathode ray tube characterized in that it comprises the step of attaching an auxiliary chuck having the same structure. The method of claim 1, The cathode is an electron gun cathode manufacturing method for electrophotographic cathode ray tube, characterized in that formed by dry electrophotographic. The method of claim 2, The auxiliary chuck electron gun cathode manufacturing method for an electrophotographic cathode ray tube, characterized in that the plastic material. The method according to claim 1 or 2, Electron-emitting material in the step of attaching the electron-emitting material is an electron gun cathode manufacturing method for an electrophotographic cathode ray tube, characterized in that formed of at least two materials of barium carbonate, strontium carbonate, calcium carbonate.