JP2965652B2 - Electron gun for cathode ray tube - Google Patents

Description

The present invention relates to an electron gun for a cathode ray tube such as a color picture tube, and more particularly to a method of dividing an anode high voltage by a resistance and supplying it to a predetermined electrode. For a cathode ray tube electron gun having a resistor for the same.

(Prior Art) Generally, a color picture tube has an envelope composed of a panel (1) and a funnel (2) integrally joined to the panel (1), as shown in FIG. (1)
A phosphor screen (3) formed of a three-color phosphor layer emitting blue, green, and red light is formed on the inner surface, and a large number of electron beam passage holes are formed inside the phosphor screen (3) so as to face the phosphor screen (3). The formed shadow mask (4) is arranged. An electron gun (7) for emitting three electron beams (6B), (6G) and (6R) into the neck (5) of the funnel (2).
Are arranged.

The electron gun (7) has three cathodes, electrodes for controlling electron emission from the cathodes and accelerating and focusing to form electron beams (6B), (6G) and (6R), and the electron beams ( 6B), (6G), and (6R) are composed of a plurality of electrodes such as electrodes for accelerating and focusing toward the phosphor screen (3), and the electrodes for accelerating and focusing toward the phosphor screen (3) include: In addition to an electrode to which an anode high voltage of about 25 to 30 kV is applied, there is an electrode to which a medium voltage of about 5 to 8 kV is applied as a focusing voltage.

Normally, the voltage of each electrode of the electron gun (7), except for the electrode to which the anode high voltage is applied, has a stem (8) sealing the end of the neck (5) in an airtight manner. It is supplied via a plurality of penetrating stem pins (9). But,
If the voltage supplied via the stem pin (9) includes a relatively high intermediate voltage such as the above-described focusing voltage, the interval between the stem pins (9) is narrow, and thus the stem (8)
In addition, withstand voltage of a socket or the like connected to the stem pin (9) becomes a problem, and the structure of the socket is particularly complicated.

Therefore, means for arranging a resistor in the envelope and dividing the high anode voltage by the resistor to obtain a predetermined medium voltage is disclosed in Japanese Utility Model Laid-Open No. 48-21561 and Japanese Utility Model Laid-Open No. 55-38484. No. 3,932,786, U.S. Pat.No.4,143,2
No. 98, etc. The arrangement of the resistor is
Since there is no adequate space in the envelope, it is located in a small space in the neck.

FIG. 7 shows an example of an electron gun in which the above resistors are arranged. This electron gun is an electron gun for an in-line type color picture tube which emits three electron beams arranged in a line composed of a center beam and a pair of side beams passing on the same plane, and has three cathodes (K) arranged in a line. Three heaters (H) inserted in each of the cathodes (K) are sequentially arranged from the cathode (K) toward the phosphor screen,
The first of an integrated structure (unitized structure) in which three electron beam passage holes corresponding to three cathodes (K) are formed.
To the fifth grid (G1) to (G5) and the convergence cup (C) fixed to the fifth grid (G5), the heater (H), the cathode (K), and the first to fifth grids. (G1) to (G5) are a pair of insulating supports (1
It is fixed together by 1). In particular, the electron gun of the illustrated example has a longer third grid (G3) and a longer fourth grid (G3).
4) is shortened to form a long-focal electron lens having a gentle potential gradient from the third grid (G3) to the fifth grid (G5). A resistor (12) is arranged along the back surface of one of the insulating supports (11). Also, a pair of insulating supports (11) and a resistor (12) disposed on the back of one of the insulating supports (11).
A linear metal member (13) is annularly attached to the third grid (G3) so as to surround the third grid (G3).

Part of the linear metal member (13) is evaporated by high-frequency heating in the process of manufacturing a color picture tube, and deposited on the inner surface of the neck (5), the resistor (12), the insulating support (11), and the like. The film (14) is formed to shield a high potential electric field, stabilize the electric field near the electron gun, and improve the withstand voltage.

In this electron gun, (15) is an internal conductive film (16) that is welded and fixed to the convergence cup (C), the tip of which is applied to the inner surface of the funnel and extends to a portion adjacent to the inner surface of the neck (5). The anode high voltage supplied to the anode terminal provided on the funnel is applied to the internal conductive film (1
6) and the fifth through the convergence cup (C)
This is a valve spacer that transmits to the grid (G5).

By the way, as shown in FIG. 8, the resistor (12) is formed to have a length of 60 mm, a width of 5.0 mm and a thickness of 1.0 mm, for example, and a convergence cup (C) from the cathode (K) side of the electron gun. An insulating substrate (17) extending up to the side of the substrate, and a mixture of ruthenium oxide and glass powder mixed with the insulating substrate (1).
7) A resistance pattern (18) of about 2000 MΩ formed in a meandering shape on one surface of the surface, and a thin insulating layer (19) made of glass having a thickness of about 50 to 200 μm and covering the resistance pattern (18). And a through hole (20) provided at a predetermined position of the insulating substrate (17) and ruthenium oxide formed on one surface of the insulating substrate (17) and connected to the resistance pattern (18) as a main component. And a voltage extraction terminal portion (22) made of a resistance member of about several kΩ and crimped and fixed to the through hole (20) by a method such as caulking.
And (2) a connection piece (23) such as an eyelet.

The resistor (12) is connected to the voltage extraction terminal (2
The connection wire (24) welded to the connection piece (23) in 2)
One end is connected to the convergence cup (C), the other end is connected to the stem pin (9), and the middle is connected to the third and fourth grids (G3) and (G4). 16), the anode high voltage of about 25 to 30 kV supplied to the fifth grid (G5) via the valve spacer (15) and the convergence cup (C) is applied to the resistance pattern (18).
, A voltage of about 12 kV is supplied to the fourth grid (G4) and a voltage of about 6 kV is supplied to the third grid (G3) from the two intermediate voltage output terminals (22).

Therefore, according to this electron gun, a stem pin conventionally required for supplying a predetermined voltage to the third grid and the fourth grid is not required, and the withstand voltage characteristics are improved, and the circuit configuration is simplified. can do.

However, as described above, in the manufacturing process of the color picture tube, the electron gun is made of a metal member (1) by high-frequency heating.
When a part of 3) is evaporated and deposited on the inner surface of the neck (5), the heat generated by the metal member (13) causes the resistance of the resistor (12).
Is heated, and the resistance nearby changes locally, so that the resistance division ratio changes, and the third and fourth grids (G3),
There is a problem that a predetermined voltage cannot be supplied to (G4) and the beam spot diameter on the phosphor screen is deteriorated.

FIGS. 9 (a) and 9 (b) show the voltage extraction terminal (2
FIG. 4 is a diagram showing a relationship between a resistance division ratio and a resistance value distribution of a resistor (12) having resistance values R1, R2, and R3 divided into three by 2), and a metal member is provided at a position A in the center of R2. If there is. A solid line (25) shown in (a) is a resistance value distribution (and resistance value) before being heated by heat generation of the metal member, and a broken line (26) is a resistance value distribution (and resistance value) after heating. is there.

The resistor (12) in this example has a length of 60 mm, a width of 5.0 mm, and a thickness of
A resistance pattern (18) with a specific resistance of 7.0 Ω · cm is formed in a meandering shape with a cross-sectional area of about 35 × 10 ⁻⁹ cm ² on one surface of an insulating substrate (17) made of 1.0 mm alumina ceramic, R1 = 500 MΩ R2 = 500 MΩ R3 = 1000 MΩ, and the resistance division ratios E1 and E2 at the middle two voltage extraction terminals (22) are E1 = 25% and E2 = 50%, respectively. Further, as shown in FIG. 10, resistance values r21, r22, r23 obtained by subdividing the resistance pattern (18) in the R2 portion.
Is r21 = 180 MΩ r22 = 120 MΩ r23 = 200 MΩ Then, when heated by the heat generated by the metal member located on the r22 portion, the r22 portion is reduced by about 42% to r22 = 70 MΩ, and the resistance division ratio E1 at the two intermediate voltage extraction terminal portions (22) is obtained. , E2 is E1 = (500/1950) x 100 = 25.6% E2 = {(500 + 450) / 1950} x 100 = 48.7%.

In other words, in the resistor of this example, when heated by the heat generated by the metal member, R2 becomes small, and the resistance division ratio E1 at one of the intermediate voltage extraction terminal portions (22) becomes 25% to 25.6%. When the anode high voltage is 25 kV, the voltage changes from 6.25 kV to 6.40 kV, and the voltage supplied to the third grid increases by 150 V. Further, the resistance division ratio E2 at the other intermediate voltage extraction terminal section (22) is changed from 50% to 48.7%, and the voltage supplied to the fourth grid is reduced by about 300 V from 12.5 kV to 12.2 kV. Therefore, the characteristics of the electron gun are significantly impaired.

(Problems to be Solved by the Invention) As described above, in order to improve the withstand voltage of the stem and the socket connected to the stem pin, the electrodes of the electron gun, such as the heater, the cathode and the grid, have been integrated. A resistor is arranged along the back surface of the insulating support to be fixed, and the resistor divides the anode high voltage by resistance to supply a relatively high medium voltage to a predetermined electrode. In order to stabilize the voltage and improve the withstand voltage, attach a linear metal member to the electrode located closer to the cathode than the electrode to which the anode high voltage is applied so as to surround the insulating support and the resistor, and manufacture a cathode ray tube. There is an electron gun in which a metal member is heated during the process to partially evaporate the metal member to form a deposited film on the inner surface of the neck, a resistor, an insulating support, and the like. However, in such an electron gun, the resistor is heated by the heat generated by the metal member when forming the above-mentioned vapor-deposited film, the resistance near the metal member locally changes, and the resistance division ratio changes. As a result, a predetermined voltage cannot be supplied to a predetermined electrode, and the characteristics of the electron gun are deteriorated.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems. Even if the resistance of a resistor locally changes due to heat generated by a metal member, a change in a resistance division ratio and a change in the total resistance of the resistor are small. Therefore, it is an object of the invention not to affect the characteristics of the electron gun.

[Configuration of the invention]

(Means for Solving the Problems) A cathode, an electrode for controlling electron emission from the cathode and accelerating and converging to form an electron beam, and an electrode for accelerating and converging the electron beam at least to which an anode high voltage is applied are provided. A plurality of electrodes including: an insulating support for integrally fixing the cathode and the plurality of electrodes; a resistor pattern arranged along the insulating support and having a predetermined resistance value; A resistor for dividing a high voltage by a resistance and supplying a predetermined voltage to at least one of the plurality of electrodes; and a plurality of resistors for preventing an influence of an electric field formed by the electrode to which the anode voltage is applied. An electron gun for a cathode ray tube having a metal member surrounding the insulating support and the resistor connected to a predetermined electrode among the plurality of electrodes; Of the turns, the resistance value of the portion facing the metal member was formed to be relatively smaller than the resistance values of the other portions.

(Operation) According to the study of the present inventors, it has been found that the rate of change of the resistance value due to heating decreases as the specific resistance value of the resistance pattern decreases. As a method of reducing the specific resistance value of the resistance pattern, there are a method of reducing the specific resistance value of the resistance material constituting the resistance pattern itself, a method of partially increasing the length of the resistance pattern, and a method of reducing the cross-sectional area. Any of these methods can reduce the rate of change of the resistance value of the resistance pattern.

Therefore, as described above, in the resistor pattern of the resistor, the resistance value of the portion facing the metal member surrounding the insulating support and the resistor is formed to be relatively smaller than the resistance value of the other portions. Thus, the rate of change of the resistance value can be reduced, and the most important resistance division ratio can be prevented from changing for the resistor that supplies the predetermined voltage by dividing the anode high voltage by resistance.

Hereinafter, the present invention will be described based on embodiments with reference to the drawings.

FIG. 1 shows an in-line type color picture tube electron gun according to an embodiment. The electron gun has three cathodes (K) arranged in a line, three heaters (H) inserted in each of the cathodes (K), and the cathode (K) arranged in this order from the cathode (K) toward the phosphor screen. First to fifth integrated structures
Grids (G1) to (G5) and their fifth grid (G5)
And a heater (H), a cathode (K), and first to fifth grids (G1) to (G5) integrally formed by a pair of insulating supports (11). Fixed. The first to fifth grids (G
1) to (G5) and the convergence cup (C) are formed with three electron beam passage holes corresponding to the three cathodes (K).

In this electron gun, the cathode (K) and the first to fifth grids (G1) to (G5) control the emission of electrons from the cathode (K), and accelerate and focus the emitted electrons to form an electron beam. The third to fifth grids (G3) to (G5) form a main electron lens unit that accelerates and focuses the electron beam on the phosphor screen. In particular, in the electron gun, the third grid (G3) constituting the main electron lens portion is made longer, and the fourth grid (G3) is formed.
4) is formed short to form a long focal length electron lens with a gentle potential gradient.

A resistor (30) extending from the cathode (K) side to the side of the convergence cup (C) is arranged along one back surface of the insulating support (11) in the electron gun. Have been. Further, a linear metal member (13) is annularly attached to the third grid (G3) so as to surround the pair of insulating supports (11) and the resistor (30).

As shown in FIGS. 2 and 3, the resistor (30) is an insulating substrate (32) made of alumina ceramic or the like.
And a resistance pattern (33) applied and formed on one surface of the insulating substrate (32); a thin insulating coating layer (34) made of glass for covering the resistance pattern (33); 32) a through hole (35) provided at a predetermined position and a number k composed mainly of ruthenium oxide and formed on one surface of the insulating substrate (32) and connected to the high resistance portion (33).
Voltage extraction terminal made of low resistance material of about Ω (36)
And a connection piece (37) such as an eyelet that is crimped and fixed to the through hole (35) by a method such as caulking and connected to the voltage extraction terminal portion (36).

In particular, the resistor (30) of this example includes a high-resistance portion (3) in which a resistance pattern (33) is formed by applying a high-resistance member composed mainly of ruthenium oxide and glass powder in a meandering shape with a predetermined cross-sectional area.
8) and a low-resistance section (39) formed at a position facing the linear metal member (13) with a larger cross-sectional area than the high-resistance section (38).

The connection wire (40) welded to the connection piece (37) of the voltage extraction terminal portion (36) allows the one end to the convergence cup (C), the other end to the stem pin (9),
An intermediate portion is connected to the third and fourth grids (G3) and (G4), and the fifth grid is connected via the anode terminal, the internal conductive film (16), the valve spacer (15) and the convergence cup (C). The anode high voltage of about 25 to 30 kV supplied to (G5) is resistance-divided by the resistance pattern (33), and approximately 12 kV is applied to the fourth grid (G4) from the middle two voltage extraction terminals (36). A voltage of about 6 kV is supplied to the three grids (G3).

Specifically, the resistance pattern (33) of the resistor (30)
Has a specific resistance of 7.0 Ω · cm mainly composed of ruthenium oxide and glass powder on one surface of an insulating substrate (32) made of alumina ceramic with a length of 60 mm, a width of 5.0 mm and a thickness of 1.0 mm
High-resistance member (38) with a meandering cross-sectional area of approximately 35 × 10 ^-9 cm ² formed by applying a high-resistance member with the same high-resistance member at a position facing the linear metal member (13) It consists of a resistance part (39) coated and formed to about 14 × 10 ^-9 cm ² , and the resistance values R1, R2, R3 between each voltage extraction terminal part (36) are R1 = 1000MΩ R2 = 500MΩ R3 = 500MΩ The resistance division ratios E1 and E2 at the two intermediate voltage output terminals (36) are E1 = 25% and E2 = 50%, respectively. Further, the resistance values r21, r22, and r23 obtained by subdividing the resistance pattern (33) of the R2 portion are (11th
R21 = 200MΩ r22 = 50MΩ r23 = 250MΩ

Such a resistor (30) is formed by applying a high-resistance member mainly composed of ruthenium oxide and glass powder on one surface of an insulating substrate (32) in a meandering manner by a method such as screen printing. While forming (38), the same high-resistance member is applied to a position facing the linear metal member (13) with a larger cross-sectional area than the high-resistance section (38) to form the resistance section (39). . Further, a low-resistance member containing ruthenium oxide as a main component is applied in a predetermined shape by a method such as screen printing around the through hole (35) provided in the insulating substrate (32). After drying, they are fired at a temperature of 700 to 900 ° C. to form a resistance pattern (33) and a voltage extraction terminal (36). Next, a paste mainly composed of lead oxide glass powder is applied on the insulating substrate (32) by the same method such as screen printing and dried, and then fired at a temperature of about 500 to 700 ° C. The resistance pattern (33) formed on the substrate (32) is covered. afterwards,
It is manufactured by attaching a connection piece (37) such as an eyelet to the through hole (35) and connecting it to the voltage extraction terminal (36).

By the way, when the resistor (30) is configured as described above,
Even when the metal member (13) is heated by high-frequency heating and is heated by heat generated when a part of the metal member (13) is evaporated, the resistance of the opposed r22 portion of the metal member (13) only slightly changes. Changes in the division ratios E1 and E2 can be significantly reduced. For example, in the above specific example, the resistance of the portion facing the metal member (13), which was r22 = 50 MΩ before the heating, was r22 = 35 MΩ after the heating. 30% reduction, but the total resistance RT of the resistor (30)
Is RT = 1985 MΩ, and the resistance division ratios E1 and E2 at the two intermediate voltage output terminals (22) are E1 = (500/1985) x 100 = 25.2% E2 = {(500 + 485) / 1985} x 100 = 49.6%, and the resistance division ratios E1 and E2 could be significantly reduced compared to conventional resistors.

Therefore, when placing such a resistor (30),
By supplying a predetermined voltage to each of the predetermined electrodes of the electron gun, that is, the third and fourth grids (G3) and (G4) in the electron gun of this example, an electron gun whose characteristics are not impaired can be obtained.

The reason why such an excellent effect is obtained can be explained as follows.

That is, the specific resistance of the resistance member mainly containing ruthenium oxide depends on the firing temperature, and the specific resistance tends to decrease as the firing is performed at a higher temperature. Therefore, the resistor (30) in which the resistance pattern (33) is formed by the resistance member mainly composed of ruthenium oxide is locally heated by the heat generated by the metal member (13), and the resistance value of the portion changes. . However, as a result of the study of the present inventors, it has been found that the change in the resistance value in this case may decrease or increase.

There are still many unclear points regarding the change in the resistance of the resistor (30), but the decrease in the resistance is due to the fact that the high-resistance member is refired at a temperature higher than the firing temperature at the time of manufacturing the resistor. As a result, the dispersion direction of the ruthenium oxide molecules and reduced ruthenium molecules that carry out electric conduction in the high-resistance member is rearranged in the direction of current flow, and the potential energy in the high-resistance member that exhibits macroscopic electrical resistance changes. It is thought to be. Regarding the increase in the resistance value, since the softening temperature of the glass constituting the insulating coating layer (34) is 400 to 500 ° C, the glass of the insulating coating layer (34) is made of a metal member (13).
This is considered to be due to diffusion into the resistance pattern (33) due to heating by the heat generated by the heat generation, thereby increasing the specific resistance of the high-resistance member. Actually, since these two phenomena proceed simultaneously,
The change in the resistance value of the resistor (30) may decrease or increase. It depends on the resistor (30)
And the heating temperature and heating time.

On the other hand, according to the results of the study by the present inventors, it has been found that the rate of change of the resistance value due to reheating decreases as the specific resistance value decreases. Therefore, in a member having a large amount of an electrically conductive material such as ruthenium oxide molecules or ruthenium molecules that carry out electrical conduction, even if the direction of dispersed arrangement of the molecules slightly changes, the change in the specific resistance is extremely small and the insulating coating layer (34)
It has been found that the change in the specific resistance value is extremely small even if the glass constituting the material diffuses into the resistance pattern (33).

Considering the resistance value of the R2 portion where the linear metal member (13) is located (see FIG. 11), r21, r22, r23
Each specific resistance of the part is ρ21, ρ22, ρ23, and each cross-sectional area is s21, s2
2, s23, each linear length along the resistance pattern is 21,22,
23, when each length of the resistance pattern is L21, L22, L23, Becomes

Now, assuming that the r22 portion of the R2 portion is most significantly heated by the heat generated by the heat generated by the linear metal member, the resulting change in the resistance value of the R2 portion is reduced to a predetermined value. In order to keep the value, r22 should be reduced and r21 and r23 should be increased accordingly.

Therefore, as described above, by forming the resistance pattern (33) in which the low-resistance portion (39) having a larger cross-sectional area than the high-resistance portion (38) is formed at the position facing the linear metal member (13). In addition, it is possible to reduce the change in the overall resistance value and to reduce the change in the resistance division ratios E1 and E2 in the intermediate voltage output terminal (36).

In the above embodiment, r2 facing the linear metal member
In order to reduce the resistance value of the two parts, the cross-sectional area was made larger than that of the high-resistance part such as the r21 part or the r23 part. There are a method of forming with a resistance member having a small specific resistance, a method of shortening the length of the resistance pattern, and a method of combining them.

FIG. 4 shows, as an example, a resistor (30) in which a meandering resistance pattern (33) is formed linearly to form a low-resistance portion (39) having a short length, and FIG. The low-resistance portion (39) is formed in the same pattern as the high-resistance portion (38) by using a resistance member having a small specific resistance, and the same effect as that of the resistor of the above embodiment can be obtained. .

Further, in the above-described embodiment, the resistor mainly composed of ruthenium oxide has been described. However, the present invention is similarly applicable to a resistor whose resistance value changes by heating.

In the above embodiment, the in-line type electron gun for a color picture tube has been described. However, the present invention can be applied not only to other electron guns for a color picture tube but also to other electron guns for a cathode ray tube.

〔The invention's effect〕

A cathode, a plurality of electrodes including an electrode for controlling electron emission from the cathode and accelerating and converging to form an electron beam, and at least an anode electrode for accelerating and converging the electron beam to which an anode high voltage is applied; And an insulating support for integrally fixing the plurality of electrodes, and a resistor pattern arranged along the insulating support and having a predetermined resistance value. A resistor for supplying a predetermined voltage to at least one of the plurality of electrodes, and in order to prevent the influence of an electric field formed by the electrode to which the anode high voltage is applied,
A cathode ray tube electron gun that is connected to a predetermined electrode of the plurality of electrodes and has a metal member surrounding the insulating support and the resistor. If the resistance value of the opposing part is formed relatively smaller than the resistance value of the other part, even if the resistor is locally heated by the heat generated by the metal member, a predetermined voltage to be supplied to a predetermined electrode is taken out. The change in the resistance division ratio at the intermediate voltage output terminal portion can be made extremely small, and an electron gun with a small change in characteristics can be constructed.

[Brief description of the drawings]

1 to 5 are explanatory views of an embodiment of the present invention.
2A and 2B are a perspective view and a front view, respectively, showing a configuration of an electron gun for an in-line type color picture tube according to one embodiment, FIG. 2 is a front view showing a configuration of the resistor, and FIG. Is an exploded perspective view showing the structure of the resistor.
4 and 5 are diagrams showing other configurations of the resistor, FIG. 6 is a diagram showing the configuration of the color picture tube, FIG. 7 is a diagram showing the configuration of the electron gun, and FIG. 9A and 9B are exploded perspective views showing the structure of the resistor, and FIGS. 9A and 9B are diagrams showing a change in the resistance division ratio of the resistor in comparison with the resistor.
FIG. 10 is an enlarged view showing a main part of the resistor. 9: Stem pin, 11: Insulating substrate 13: Metal member, 15: Valve spacer 30: Resistor, 32: Insulating substrate 33: Resistance pattern, 34: Insulating coating layer 35: Through hole, 36: Voltage extraction terminal 37: Connection piece, 38: High resistance part 39: Low resistance part, 40: Connection C: Convergence cup G1: First grid, G2: Second grid G3 … Third grid, G4… Fourth grid G5… Fifth grid, H… Heater K… Cathode

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Shinpei Koshigoe 1-9-2 Harara-cho, Fukaya-shi, Saitama Prefecture Inside the Toshiba Fukaya CRT plant (72) Inventor Shigeo Fukuda 72, Horikawa-cho, Saiwai-ku, Kawasaki-shi, Kanagawa Prefecture Address Toshiba Electronic Device Engineering Co., Ltd. (56) References JP-A-2-223136 (JP, A) JP-A-63-80450 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) ) H01J 29/46-29/68

Claims (1)

(57) [Claims] A plurality of electrodes including a cathode, an electrode for controlling electron emission from the cathode and accelerating and converging to form an electron beam, and an electrode for accelerating and converging the electron beam at least to which an anode high voltage is applied. An electrode, an insulating support that integrally fixes the cathode and the plurality of electrodes,
A resistor pattern having a predetermined resistance value disposed along the insulating support, for dividing the anode high voltage by the resistance pattern and supplying a predetermined voltage to at least one of the plurality of electrodes; And a metal surrounding the insulating support and the resistor connected to a predetermined electrode of the plurality of electrodes to prevent the influence of an electric field formed by the electrode to which the anode voltage is applied. A cathode ray tube, wherein the resistance pattern of the resistor is formed such that a resistance value of a portion facing the metal member is relatively smaller than resistance values of other portions. Tube electron gun.