JPH0721920A - Manufacture of cathode-ray tube - Google Patents

Abstract

PURPOSE:To provide a manufacturing method of a cathode-ray tube by which an effective knocking process can be carried out. CONSTITUTION:In the manufacturing method of a cathode-ray tube, a knocking process is included between a focus part electrode 1 connected to a built-in resistance 12 for partial pressure, and focus part electrodes G3, G4 provided in front of and behind the focus part electrode. The focus part electrode 10 connected to the built-in resistor for partial pressure is preliminarily grounded by a short-circuit 14, and after the knocking process is carried out between the focus part electrode 10 and the one focus part electrodes G4 provided in front of and behind the focus part electrode, the short-circuit 14 is cut. The knocking process is carried out between the focus part electrode 10 connected to the built-in resistor for partial pressure and the other focus part electrode G3 provided in front of and behind the focus part electrode.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a cathode ray tube, and more particularly to a method for manufacturing a cathode ray tube characterized by a knocking process.

[0002]

2. Description of the Related Art In recent years, as the size and performance of cathode ray tubes have increased, the demand for focus characteristics of the cathode ray tubes has increased. Therefore, many methods for reducing the spherical aberration in the electron lens of the cathode ray tube have been adopted. One of them is that the electron gun of the cathode ray tube is provided with an auxiliary electrode, the auxiliary electrode is connected to a built-in resistor for voltage division, and a high voltage is applied to one end of the built-in resistor. Applied a high voltage that could not be supplied from the
There is a method of expanding the electric field of the electron lens unit.

A conceptual diagram of a single main lens type electron gun portion of a cathode ray tube having no built-in resistor for voltage division is shown in FIG. Further, a conceptual diagram of an electric field expansion type electron gun portion having a built-in resistor for voltage division is shown in FIG. In FIG.
K is a cathode, G1 is a first grid electrode, G2 is a second grid electrode, G3 is a third grid electrode, G4 is a fourth grid electrode, and CV is a convergence electrode. Also, 12
Is a built-in resistor for voltage division, and 10 is an auxiliary electrode connected to a part of the built-in resistor 12. The built-in resistor 12 for voltage division is
The resistance pattern is formed on the insulating substrate 16. Each of the third grid electrode G3, the fourth grid electrode G4, and the auxiliary electrode 10 corresponds to a focus portion electrode, and these constitute a focus portion. By providing the auxiliary electrode 10, an expansion lens is configured and the aperture of the electron lens is increased. The cathode K, the first grid electrode G1, the second grid electrode G2, the third grid electrode G3, and the fourth grid electrode G4 are supported by a support body (not shown) made of bead glass.

If sharp projections or the like are present on each grid electrode or the like forming the electron lens, abnormal discharge may occur during operation of the cathode ray tube. In order to prevent such abnormal discharge, a knocking process is performed in the manufacturing process of the cathode ray tube. In this knocking process, a discharge is generated in advance at a portion where a discharge easily occurs such as a sharp projection of each grid electrode or the like, and the projection or the like is melted and removed. In FIGS. 3B and 3D, the third part of the cathode ray tube is shown.
Grid electrode G3, fourth grid electrode G4 and auxiliary electrode 1
An example of a voltage and a knocking voltage of the cathode ray tube applied to 0 when the cathode ray tube is in operation is shown. The knocking voltage refers to the voltage applied to each electrode during the knocking process.

During operation of the cathode ray tube, the fourth grid electrode G4 is passed through the anode button and the interior carbon (not shown).
A high anode voltage is applied to. Further, for example, a voltage is applied to the third grid electrode G3 through a stem portion (not shown). Further, a voltage (for example, 65% of the anode voltage) obtained by dividing the anode voltage applied to the fourth grid electrode G4 by the internal resistor 12 for voltage division is applied to the auxiliary electrode 10.

[0006]

In the cathode ray tube which does not have a built-in resistor for voltage division shown in FIG. 3 (A),
Since the difference in knocking voltage between the fourth grid electrode G4 and the third grid electrode G3 is as much as 50 kV, the knocking process can melt and remove the protrusions and the like.

However, in the cathode ray tube having the internal resistor 12 for voltage division shown in FIG. 3C, the difference in knocking voltage between the fourth grid electrode G4 and the auxiliary electrode 10 is only 17.5 kV, for example. Absent. Therefore, even if the knocking process is performed, the protrusions and the like do not melt, and the protrusions and the like cannot be removed.

Therefore, an object of the present invention is to provide a method of manufacturing a cathode ray tube having an electron gun having a built-in resistor for voltage division and a focus electrode connected to the built-in resistor, which can perform an effective knocking process. To do.

[0009]

The above object is to provide a cathode ray including a knocking process between a focus portion electrode connected to a built-in resistor for voltage division and a focus portion electrode provided before and after the focus portion electrode. A method of manufacturing a tube, comprising: (a) a focus part electrode connected to a built-in resistor for voltage division is grounded in advance by a short circuit, and the focus part electrode is provided before and after the focus part electrode. A step of performing a knocking process with one of the focus section electrodes, and (b) a step of disconnecting the short circuit,
(C) A book including a step of performing a knocking process between a focus electrode connected to a built-in resistor for voltage division and the other focus electrode provided before and after the focus electrode. This can be achieved by the method for manufacturing a cathode ray tube of the invention.

Depending on the structure of the electron gun, the steps (a) and (b) can be repeated a desired number of times.

[0011]

In the present invention, first, the knocking process is performed between the focusing electrode connected to the built-in resistor for voltage division and one of the focusing electrodes provided before and after the focusing electrode. At this time, the focus portion electrode connected to the internal resistor for voltage division is grounded by the short circuit. Therefore, the potential of the focus portion electrode is approximately 0 V, and the difference in knocking voltage between the focus portion electrode and the one focus portion electrode is substantially equal to the voltage applied to the one focus portion electrode. That is, the knocking process can be performed with a large knocking voltage difference, and the knocking process having a sufficient effect can be performed.

After the knocking process is completed, the short circuit is cut off, and then the focusing electrode connected to the built-in resistor for voltage division and the other focusing electrode provided before and after this focusing electrode. Knocking process is performed between. The focus electrode connected to the built-in resistor,
The voltage divided by the built-in resistor for voltage division is applied. If the other focusing electrode is grounded, the divided voltage corresponds to the knocking voltage difference, and the knocking process having a sufficient effect can be performed.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings.

(Embodiment 1) FIG. 1A is a conceptual diagram of a part of an electric field expansion type electron gun having a built-in resistor for voltage division, which is suitable for manufacturing by the method for manufacturing a cathode ray tube of the present invention. Show. However, FIG. 1A shows a state before disconnection of a short circuit described later. The electric field expansion type electron gun includes a cathode K, a first grid electrode G1, a second grid electrode G2, a third grid electrode G3, a fourth grid electrode G4, and a convergence electrode CV. Cathode K, first grid electrode G1 ~
The fourth grid electrode G4 is fixed to a support body (not shown) made of bead glass.

This electron gun is equipped with an auxiliary electrode 10 and a built-in resistor 12 for voltage division. Built-in resistor 1 for voltage division
2 is formed on an insulating substrate 16 made of alumina, for example, by printing a resistance paste in which a conductive material such as ruthenium oxide is mixed in an insulating material such as lead glass in a zigzag pattern, and drying and firing. Can be formed. An anode voltage is applied to one end of the built-in resistor 12. The other end of the built-in resistor 12 is grounded.

The auxiliary electrode 10 is electrically connected to a part of the internal resistor 12 for voltage division. The auxiliary electrode 10 corresponds to a focusing electrode connected to a built-in resistor for voltage division. The third grid electrode G3 and the fourth grid electrode G4 correspond to focus part electrodes provided before and after the focus part electrode connected to the built-in resistor. The focus unit is configured by these.

The focusing electrode (auxiliary electrode 10) connected to the built-in resistor for voltage division is grounded by the short circuit 14. The short circuit 14 is also formed on the insulating substrate 16, and like the built-in resistor 12, for example, a resistance paste in which a conductive material such as ruthenium oxide is mixed with an insulating material such as lead glass is printed, dried, and fired. Can be formed by. The auxiliary electrode 10 may be grounded via a part of the built-in resistor 12 and the short circuit 14.

During operation of the cathode ray tube, the fourth grid electrode G4 is passed through the anode button and internal carbon (not shown).
A high anode voltage is applied to. Further, for example, a voltage is applied to the third grid electrode G3 through a stem portion (not shown). Further, a voltage (for example, 65% of the anode voltage) obtained by dividing the anode voltage applied to the fourth grid electrode G4 by the internal resistor 12 for voltage division is applied to the auxiliary electrode 10.

Details of the knocking process in the first embodiment will be described below.

[First-stage knocking process] In the electron gun in the state shown in FIG. 1A, first, the first-stage knocking process is performed. That is, the focus portion electrode (auxiliary electrode 10) connected to the internal resistor 12 for voltage division is grounded by the short circuit 14, and the focus portion electrode (auxiliary electrode 10) and the front and rear of the focus portion electrode are provided. Knocking treatment is performed with one of the focus portion electrodes thus formed (the fourth grid electrode G4 in the first embodiment).

Since the auxiliary electrode 10 is grounded by the short circuit 14, the electric potential of the auxiliary electrode 10 is approximately 0V. A high voltage, for example 50 kV, is applied to the fourth grid electrode G4 through the anode button and the interior carbon. That is, in this first-stage knocking process, the difference in knocking voltage is 50 kV. Therefore, the knocking process can be performed with a large knocking voltage difference,
It is possible to perform a knocking process having a sufficient effect. The value of the knocking voltage in the knocking process in the first stage is shown in FIG.

[Step of Cutting Short Circuit] After that, as shown in FIG. 1C, the short circuit 1 is formed by using, for example, a laser.
Cut 4.

[Second-stage knocking process] Next, the focus portion electrode (auxiliary electrode 10) connected to the built-in resistor for voltage division, and the other of the focus portion electrodes provided before and after the auxiliary electrode 10 (embodiment) In No. 1, a knocking process is performed with the third grid electrode G3).

During the second-stage knocking process, the auxiliary electrode 10 is applied with a voltage divided by the internal resistor 12 for voltage division, for example, 32.5 kV. If the other focusing electrode (third grid electrode G3) is grounded, the divided voltage corresponds to the difference in knocking voltage,
It is possible to perform a knocking process having a sufficient effect. The value of the knocking voltage in the second stage knocking process is shown in FIG.

(Embodiment 2) FIG. 2A shows an electric field expansion type suitable for manufacturing by the method of manufacturing a cathode ray tube according to the present invention and having a built-in resistor for voltage division which is slightly different from that of Embodiment 1. The conceptual diagram of the part of an electron gun is shown. In Example 2,
The first auxiliary electrode 10A and the second auxiliary electrode 10B are provided between the third grid electrode G3 and the fourth grid electrode G4. Each of the third grid electrode G3, the fourth grid electrode G4, and the first and second auxiliary electrodes 10A and 10B corresponds to a focus portion electrode, and these constitute a focus portion.

The first auxiliary electrode 10A is electrically connected to a part of the built-in resistor 12, and is grounded by the first short circuit 14A. Second auxiliary electrode 10B
Similarly, is electrically connected to a part of the built-in resistor 12 and is grounded by the second short circuit 14B. FIG. 2A shows these short circuits 14A and 14B.
Shows the state before disconnection. The built-in resistor 12 and the first and second short circuits 14A and 14B can have the same structure as that of the first embodiment. In addition, the first and second auxiliary electrodes 10A,
10B may be grounded via a part of the built-in resistor 12 and the first and second short circuits 14A and 14B.

When the first auxiliary electrode 10A is regarded as the focus portion electrode connected to the internal resistor for voltage division, the third grid electrode G3 and the second auxiliary electrode 10B are connected to the internal resistor to the focus portion. Electrode (first auxiliary electrode 10
It corresponds to the focus portion electrodes provided before and after A).
When the second auxiliary electrode 10B is regarded as the focus electrode connected to the internal resistor for voltage division, the fourth grid electrode G4 and the first auxiliary electrode 10A are connected to the internal resistor to the focus electrode. It corresponds to focus portion electrodes provided before and after the (second auxiliary electrode 10B).

During operation of the cathode ray tube, the fourth grid electrode G4 is passed through the anode button and the interior carbon (not shown).
A high anode voltage is applied to. Further, for example, a voltage is applied to the third grid electrode G3 through a stem portion (not shown). Further, a voltage obtained by dividing the anode voltage applied to the fourth grid electrode G4 by the internal resistor 12 for voltage division is applied to each of the first and second auxiliary electrodes 10A and 10B.

Details of the knocking process in the second embodiment will be described below.

[First-stage knocking process] In the electron gun in the state shown in FIG. 2A, first-stage knocking process is performed. That is, the second short circuit 14B
Therefore, the focus portion electrode connected to the internal resistor 12 for voltage division (in the knocking process of the first stage,
The second auxiliary electrode 10B) is grounded, and this focus electrode (second auxiliary electrode 10B) and one of the focus electrodes provided before and after this focus electrode (this knocking process in the first step) In, the knocking process is performed with the fourth grid electrode G4).

The second auxiliary electrode 10B is the second short circuit 1
Since it is grounded by 4B, the second auxiliary electrode 10
The potential of B is almost 0V. A high voltage is applied to the fourth grid electrode G4 through the anode button and the interior carbon. That is, in the knocking process of the first stage,
The knocking voltage is a high voltage applied to the fourth grid electrode G4. Therefore, the knocking process can be performed with a large knocking voltage difference, and the knocking process having a sufficient effect can be performed.

[Step of cutting the second short circuit] After that, as shown in FIG. 2B, the second short circuit 14B is cut by using, for example, a laser.

[Second-stage knocking process] Next, one of the focus electrode (first auxiliary electrode 10A) connected to the built-in resistor for voltage division and the focus electrode provided before and after the auxiliary electrode 10 (In this second-stage knocking process, the knocking process is performed with the second auxiliary electrode 10B).

During the second-step knocking process, the first short circuit 14A has not been cut yet, so that the focus electrode (first auxiliary electrode 10A) connected to the built-in resistor for voltage division has the first voltage. It is grounded by the short circuit 14A and its potential is almost 0V. Also, already the second
Since the short circuit 14B is disconnected, the high voltage divided by the voltage-dividing built-in resistor 12 is applied to one focus portion electrode (second auxiliary electrode 10B). Therefore, the high voltage applied to the second auxiliary electrode 10B corresponds to the difference in knocking voltage, and the knocking process having a sufficient effect can be performed.

[Step of cutting the first short circuit] After that, as shown in FIG. 2C, the second short circuit 14B is cut by using, for example, a laser.

[Third-stage knocking process] Next, the focus electrode connected to the built-in resistor for voltage division (in the third-stage knocking process, the first auxiliary electrode 1
0A) and the other of the focusing electrode provided before and after the first auxiliary electrode 10A (in the third knocking process, the third grid electrode G3) is knocked.

Since the first short circuit 14A is already disconnected during the knocking process of the third stage, the high voltage divided by the voltage dividing built-in resistor 12 is applied to the first auxiliary electrode 10A. To be done. If the other focus portion electrode (third grid electrode G3) is grounded, the high voltage applied to the first auxiliary electrode 10A corresponds to the difference in knocking voltage, and a knocking process having a sufficient effect is performed. You can

Although the present invention has been described based on the preferred embodiments, the present invention is not limited to these embodiments. The structure of the electron gun described in the embodiments, various numerical values, and values such as knocking voltage are examples, and can be changed as appropriate. Also, the method of applying the voltage to each electrode can be changed as appropriate. [First-stage knocking process] in Example 2 and subsequent [short-circuit cutting process]
May be repeated as many times as necessary depending on the structure of the electron gun. The manufacturing method or constituent material of the built-in resistor or the short circuit can be appropriately changed according to desired characteristics, specifications, and design values.

[0039]

According to the method of manufacturing a cathode ray tube of the present invention,
It is possible to execute the knocking voltage with a voltage difference higher than that of the related art, and it is possible to perform an effective knocking process.

[Brief description of drawings]

FIG. 1 is a conceptual diagram of an electron gun in each step for explaining an embodiment of a method of manufacturing a cathode ray tube according to the present invention.

FIG. 2 is a conceptual diagram of an electron gun in each step for explaining another embodiment of the method of manufacturing a cathode ray tube according to the present invention.

FIG. 3 is a conceptual diagram of a conventional cathode ray tube electron gun.

[Explanation of symbols]

 K cathode G1 first grid electrode G2 second grid electrode G3 third grid electrode G4 fourth grid electrode CV convergence electrode 10 auxiliary electrode 10A first auxiliary electrode 10B second auxiliary electrode 12 internal voltage dividing resistor 14 short circuit 14A First short circuit 14B Second short circuit 16 Insulating substrate

Claims (2)

[Claims] 1. A method of manufacturing a cathode ray tube comprising a knocking process between a focus electrode connected to a built-in resistor for voltage division and a focus electrode provided before and after the focus electrode, comprising: B) The focus portion electrode connected to the built-in resistor for voltage division is grounded in advance by a short circuit, and between this focus portion electrode and one of the focus portion electrodes provided before and after this focus portion electrode. (B) disconnecting the short circuit, and (c) the focus electrode connected to the built-in resistor for voltage division, and the focus electrode provided before and after the focus electrode. A step of performing a knocking process with the other of,
A method of manufacturing a cathode ray tube, comprising: 2. The method of manufacturing a cathode ray tube according to claim 1, wherein the steps (a) and (b) are repeated a desired number of times.