JPH08315750A - Color picture tube and its manufacture - Google Patents

Abstract

PURPOSE: To improve the withstand voltage characteristic of a color picture tube to supply prescribed voltage to a prescribed electrode of an electron gun through a resistor. CONSTITUTION: A color picture tube inside which an electron gun 17 whose main lens part is composed of a focusing electrode, an intermediate electrode and a final accelerating electrode and a resistor 7 to supply prescribed voltage to the intermediate electrode by dividing high voltage to be supplied to its final accelerating electrode are arranged, is provided. The final accelerating electrode and the intermediate electrode are electrically connected to each other by a shape memory alloy member 29 which does not release electric continuity at a temperature or less added in a manufacturing process of the color picture tube and is restored to a shape of releasing electric continuity at the temperature or more, and this shape memory alloy member is formed as a structure installed in a condition of being restored to a shape of releasing electric continuity to either one of the final accelerating electrode and the intermediate electrode.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color picture tube and a manufacturing method thereof, and more particularly to a color picture tube having an intermediate electrode to which a voltage is applied to a main lens portion through a resistor and a manufacturing method thereof.

[0002]

2. Description of the Related Art Presently, a color picture tube has an in-line type electron gun which emits three electron beams arranged in a line passing through the same plane, and a deflection device generates the three electron beams emitted from this electron gun. By deflecting the pincushion-type horizontal deflection magnetic field 1H shown in FIG. 8 (a) and the barrel-type vertical deflection magnetic field 1V shown in FIG. 8 (b), three electron beams can be displayed on the phosphor screen without the need for circuit correction means. The mainstream is the self-convergence in-line type color picture tube that can concentrate on the.

However, this self-convergence in-line type color picture tube has a horizontal and vertical deflection magnetic field of 1H and 1V.
Due to the inhomogeneity of, the cross-sectional shapes of the electron beams 2B, 2G, and 2R deflected by these deflection magnetic fields 1H and 1V are weakened in the horizontal focusing, as shown for the electron beam 2B in FIG. As shown in FIG. 9, the beam spot 3c in the central part of the screen becomes almost a perfect circle, while the beam spot 3p in the peripheral part of the screen is subjected to the deflection distortion in which the vertical focusing is strengthened. 4 has a shape including a halo portion 5 having a low brightness extending in the vertical direction. Therefore, there is a problem that the resolution of the peripheral portion of the screen is deteriorated.

As one of means for improving the deterioration of resolution due to the deflection distortion, Japanese Patent Application Laid-Open No. Sho 64 (1994) filed by the present inventors.
Japanese Patent Publication No. 38947-B discloses the electron gun shown in FIG. This electron gun has three cathodes KB arranged in a row.
, KG, KR, three heaters (not shown) for individually heating the cathodes KB, KG, KR, and the first to sixth electrodes sequentially arranged in the phosphor screen direction from the cathodes KB, KG, KR. G1 to G6, 5th and 6th
Two intermediate electrodes Gm1, G arranged between the electrodes G5, G6
m2 and a shield cup CS attached to the end of the sixth electrode G6 on the phosphor screen side.

In this electron gun, the cathodes KB, KG, K
An electron beam generator for controlling electron emission from the cathodes KB, KG, KR and focusing the emitted electrons into an electron beam by R and the first, second and third electrodes G1, G2, G3. The third, fourth and fifth electrodes G3,
G4, G5, the two intermediate electrodes Gm1, Gm2, and the sixth electrode G6 form a plurality of electron lenses for focusing the electron beam from the electron beam generator. In particular, the fifth electrode G5, the two intermediate electrodes Gm1 and Gm2, and the sixth electrode G6 finally form a main lens portion for focusing the electron beam on the phosphor screen.

Fifth electrode G5 forming the main lens portion
A focusing voltage on which an AC component, which changes in a parabolic shape in synchronization with the deflection of the electron beam of the deflecting device, is superimposed is applied to the (focusing electrode), and an anode high voltage is applied to the sixth electrode G6 (final acceleration electrode). The intermediate electrodes Gm1 and Gm2 are respectively supplied with a predetermined voltage obtained by dividing the anode high voltage applied to the sixth electrode G6 by the resistor 7 arranged along the electron gun.

By applying such a voltage, the main lens portion relatively strongly focuses the electron beam in the vertical direction by the fifth electrode G5 and the intermediate electrode Gm1 adjacent to the fifth electrode G5. One quadrupole lens is formed, and the intermediate electrode Gm2 and the sixth electrode G6 adjacent to this intermediate electrode Gm2 form a second quadrupole lens that relatively strongly diverges the electron beam in the vertical direction. These first and second quadrupole lenses are balanced when the electron beam goes to the center of the screen without being deflected by the deflecting device, and the beam spot at the center of the screen becomes substantially circular. Further, when the electron beam is deflected by the deflecting device toward the peripheral portion of the screen, the focusing voltage applied to the fifth electrode G5 rises,
The potential difference between the fifth electrode G5 and the intermediate electrode Gm1 adjacent thereto becomes small. As a result, the first quadrupole lens becomes weak, and the electron beam is strongly influenced by the second quadrupole lens and diverges mainly in the vertical direction. As a result, the deflection distortion generated by the deflecting device, which is strongly focused in the vertical direction on the electron beam by the horizontal and vertical deflection magnetic fields, is canceled out, and the beam spot in the peripheral portion of the screen can be made substantially circular.

However, this electron gun has the fifth and sixth electrodes G5.
, G6, two intermediate electrodes Gm1 and Gm2 are arranged, so that the distance between the fifth electrode G5 and the sixth electrode G6 is 5 to 6
mm, which is larger than about 1 mm, which is the distance between the focusing electrode and the final accelerating electrode of an ordinary electron gun in which the intermediate electrodes Gm1 and Gm2 are not arranged. Therefore, there is a problem that sufficient withstand voltage characteristics cannot be obtained.

That is, in general, in the manufacturing process of a color picture tube, the cathodes KB, KG, KR and the first to fifth electrodes G1 to G5 are used in order to improve the withstand voltage characteristics.
Is connected to the ground, and a voltage higher than that when driving a color picture tube is applied to the sixth electrode G6 to remove dust and burrs adhering to the electrodes of the electron gun to increase the withstand voltage. In the above electron gun, since the distance between the fifth electrode G5 and the sixth electrode G6 is large, it is difficult to generate a spark between the electrodes and it is not possible to sufficiently remove dust and burrs adhering to the electrodes. . Even when a high voltage is applied to the sixth electrode G6, the intermediate electrodes Gm1 and Gm2 between the fifth and sixth electrodes G5 and G6 are connected to the resistor 7 having a high resistance value and are almost electrically floated. Therefore, during the withstand voltage treatment, the intermediate electrodes Gm1 and Gm2 merely serve as relay points between the sixth electrode G6 and the fifth electrode G5, and between the intermediate electrodes Gm1 and Gm2 and between the intermediate electrode Gm1 and the fifth electrode G5. A spark is unlikely to occur between and. Therefore, sufficient withstand voltage characteristics cannot be obtained.

In order to generate a spark between the intermediate electrodes Gm1 and Gm2 and between the intermediate electrode Gm1 and the fifth electrode G5, a higher voltage may be applied to the sixth electrode G6. When the voltage applied to G6 is increased,
The energy of the spark generated between the electrodes becomes too high,
On the contrary, the surface of the electrode is roughened.

[0011]

As described above, as means for improving the deterioration of the resolution in the peripheral portion of the screen of the self-convergence in-line type color picture tube, three electron guns are arranged in a row, and these cathodes are arranged. Fluorescence of three heaters for heating separately, first to sixth electrodes sequentially arranged in the phosphor screen direction from the cathode, two intermediate electrodes and sixth electrode arranged between the fifth and sixth electrodes. Fifth electrode (focusing electrode) which is composed of a shield cup attached to the end portion on the body screen side and constitutes the main lens portion thereof
, A dynamic focus voltage on which an AC component that changes in a parapolar shape is superimposed in synchronization with the deflection of the electron beam of the deflecting device, and an anode high voltage is applied to the sixth electrode (final acceleration electrode). It has been proposed to divide a high voltage of the anode applied to the sixth electrode by a resistor arranged on the intermediate electrode along the electron gun to supply a predetermined voltage.

However, if the electron gun is constructed as described above,
The distance between the fifth electrode and the sixth electrode is larger than the distance between the focusing electrode and the final accelerating electrode of a normal electron gun, and sparks are generated between the electrodes during the withstand voltage process performed in the manufacturing process of the color picture tube. It is difficult to do so, and there is a problem that sufficient withstand voltage characteristics cannot be obtained.

The present invention has been made in order to solve the above problems, and improves the withstand voltage characteristic of a color picture tube in which a predetermined voltage is supplied to a predetermined electrode of an electron gun through a resistor. The purpose is to do.

[0014]

An electron beam generator having a cathode and a plurality of electrodes, and a main lens portion for focusing an electron beam obtained from the electron beam generator on a phosphor screen are provided. Focusing electrodes sequentially arranged in the phosphor screen direction from the electron beam generator,
A color image in which an electron gun including one or more intermediate electrodes and a final accelerating electrode and a resistor for dividing a high voltage supplied to the final accelerating electrode and supplying a predetermined voltage to the intermediate electrode are arranged in a tube. In the tube, the final accelerating electrode and the intermediate electrode do not release electrical conduction below the temperature applied in the manufacturing process of the color picture tube, but are electrically restored by the shape memory alloy member that restores the electrical conduction above the above temperature. Then, the shape memory alloy member was attached to one of the final accelerating electrode and the intermediate electrode in a state of being restored to the shape in which the electrical connection was released.

Further, it has an electron beam generating portion composed of a cathode and a plurality of electrodes, and a main lens portion for focusing the electron beam from the electron beam generating portion on the phosphor screen, and the main lens portion is the electron beam generating portion. From the electron gun consisting of a focusing electrode, one or more intermediate electrodes and a final accelerating electrode sequentially arranged in the phosphor screen direction, and a high voltage supplied to the final accelerating electrode is divided to supply a predetermined voltage to the intermediate electrode. In the method of manufacturing a color picture tube in which a resistor to be arranged in the tube, the final accelerating electrode and the intermediate electrode are not released from electrical continuity below the temperature added in the manufacturing process of the color picture tube, and above the temperature. It is electrically connected by a shape memory alloy member that restores a shape that releases electrical continuity and subjected to withstand voltage treatment, and after the withstand voltage treatment, the shape memory alloy member is used in the manufacturing process of the color picture tube. And to release the electrical connection between the final accelerating electrode and the intermediate electrode is heated to above Waru temperature.

[0016]

When the color picture tube is constructed as described above and is manufactured by the above method, a color image is formed between the final accelerating electrode and the intermediate electrode connected to the resistor for dividing the high voltage supplied to the final accelerating electrode. Focusing electrode and final accelerating electrode are formed by electrically connecting with a shape memory alloy member that does not release electrical conduction below the temperature applied in the manufacturing process of the tube but restores the shape that releases electrical conduction above the above temperature. The space between the intermediate electrode and the focusing electrode can be temporarily replaced with the space between the focusing electrode and the intermediate electrode, and sufficient sparks are generated between the intermediate electrode and the focusing electrode during the withstand voltage treatment performed in the manufacturing process of the color picture tube. After the withstand voltage treatment, the color picture tube having a desired withstand voltage characteristic can be obtained by disconnecting the focusing electrode and the final accelerating electrode.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described based on embodiments with reference to the drawings.

FIG. 1 shows an in-line type color picture tube which is one of the embodiments. This color picture tube has an envelope composed of a panel 10 and a funnel-shaped funnel 11 integrally joined to the panel 10, and the inner surface of the panel 10 has a vertical direction (light emitting in blue, green, and red). A phosphor screen 12 made of a striped three-color phosphor layer is formed in the Y-axis direction), and a shadow mask 13 is arranged inside the phosphor screen 12 so as to face the phosphor screen 12.
On the other hand, in the neck 15 of the funnel 11, electrons which will be described later emit three electron beams 16B, 16G, 16R arranged in a row and composed of a center beam 16G and a pair of side beams 16B, 16R (not shown) that pass on the same horizontal plane. A gun 17 is provided. A resistor 7 is arranged in the neck 15 along the electron gun 17. Then, the three electron beam 16B emitted from the electron gun 17
, 16G, 16R are deflected by the horizontal and vertical deflection magnetic fields generated by the deflection device 18 mounted outside the funnel 11, and the phosphor screen 12 is horizontally and vertically scanned to form a structure for displaying a color image. Has been done.

As shown in FIGS. 2 and 3, the electron gun 17 has three cathodes KB, KG, KR arranged in a line in the horizontal direction (X-axis direction), and these cathodes KB, KG.
, KR separately heated by three heaters (not shown), and the first to sixth electrodes G1 to G6 sequentially arranged in the phosphor screen direction from the cathodes KB, KG, KR.
, Two intermediate electrodes Gm1 and Gm2 arranged between the fifth and sixth electrodes G5 and G6 and a shield cup Cs attached to the end of the sixth electrode G6 on the phosphor screen side, and its cathode KB, KG, KR, heaters, first to sixth electrodes G1 to G6, and intermediate electrodes Gm1 and Gm2 are integrally fixed by a pair of insulating support rods (not shown).

Each of the electrodes G1 to G6, Gm1 and Gm2 is an electrode having an integral structure. The distance between the first electrode G1 and the second electrode G2 is about 0.1 to 0.2 mm.
The distance between 2 and the third electrode G3 is about 1 mm, the distance between the third electrode G3 and the fourth electrode G4, and the distance between the fourth electrode G4 and the fifth electrode G5 is 1 mm or less, respectively, and the fifth electrode G5 and the intermediate electrode Gm1, The distance between the middle electrodes Gm1 and Gm2, the middle electrode Gm2 and the sixth electrode G6 is about 1 mm, and the distance between the fifth electrode G5 and the sixth electrode G6 is 5 to 6 mm.

The above-mentioned electrodes G1 to G6, Gm1, Gm2
And the shield cup Cs has three cathodes KB,
Corresponding to KG and KR, three circular electron beam passage holes each having a predetermined size are formed. Especially the fifth electrode G
The electron beam passage holes on the surface of the fifth electrode G6 facing the intermediate electrode Gm1 and on the surface of the sixth electrode G6 facing the intermediate electrode Gm2 are circular or non-circular.

In this electron gun 17, the cathodes KB, KG
, KR and the first, second and third electrodes G1, G2, G3, which are successively adjacent to the cathodes KB, KG, KR, control the electron emission from the respective cathodes KB, KG, KR and release the emitted electrons. An electron beam generator for focusing and forming an electron beam is formed, and the third, fourth and fifth electrodes G3, G are formed.
4, G5, two intermediate electrodes Gm1, Gm2 and sixth electrode G6
As a result, a plurality of electron lenses for focusing the electron beams from the electron beam generator to G3 are formed. Especially the 5th
The electrode G5 (focusing electrode), the two intermediate electrodes Gm1 and Gm2, and the sixth electrode G6 (final accelerating electrode) form a main lens part for finally focusing the electron beam on the phosphor screen.

The cathodes KB, KG, KR and the first
Through the fifth electrodes G1 to G5, a plurality of stem pins 21 (see FIG. 1) are embedded in the stem 20 that seals the end of the neck 15.
Voltage) via the sixth electrode G6 and 2
Each of the intermediate electrodes Gm1 and Gm2 has an anode terminal 22 provided on the large-diameter portion of the funnel 11, an inner conductive film 23 and a shield cup formed by coating from the inner surface of the large-diameter portion of the funnel 11 to the inner surface of the adjacent portion of the neck 15. A voltage is supplied through a valve spacer 24 (see FIG. 1) made of an elastic body attached to Cs and in pressure contact with the inner conductive film 23.

About 1 for each of the cathodes KB, KG, KR.
A voltage in which a video signal corresponding to an image is superimposed is applied to a DC voltage of 80V, and the first electrode G1 is grounded. The second electrode G2 and the fourth electrode G4 are connected in a tube, and a DC voltage of about 800 V is applied to the second and fourth electrodes G2 and G4. The third electrode G3 and the fifth electrode G5 are connected in a tube, and the third and fifth electrodes G3 and G5 are 8 to 9 k apart.
A dynamic focus voltage in which a parabolic AC component that changes in synchronization with the deflection of the deflection device is superimposed is applied to the DC voltage of V. An anode high voltage of about 30 kV is applied to the sixth electrode G6. The above anode high voltage is divided by the resistor 7 into the two intermediate electrodes Gm1 and Gm2, and about 40% of the anode high voltage is applied to the intermediate electrode Gm1 and about 65% is applied to the intermediate electrode Gm2. It

The resistor 7 is composed of cathodes KB, KG, KR of the electron gun 17, a heater and electrodes G1 to G6.
, Gm1 and Gm2 are integrally fixed to each other, the one of the pair of insulating support rods is disposed on the back surface (the surface side facing the inner surface of the neck) of one of the insulating support rods, and the terminal portion 26a at one end is the stem pin 2
1 is grounded directly or via the variable resistor 27, and the intermediate terminal portions 26c and 26d are respectively connected to the intermediate electrode Gm.
The anode high voltage, which is connected to 1 and Gm2 and is supplied to the terminal portion 26b at the other end, is divided to supply predetermined voltages to the intermediate electrodes Gm1 and Gm2, respectively.

Further, in the electron gun 17 shown in FIGS.
Further, as shown in FIG. 4A, one end of a shape memory alloy member 29 having a coil shape is attached to the sixth electrode G6. The shape memory alloy member 29 is made of a shape memory alloy which does not restore to its original shape at a temperature equal to or lower than the temperature applied in the manufacturing process of the color picture tube, for example, during exhaust, but restores to a coil shape at a temperature higher than the temperature applied in the manufacturing process. , First figure 4
As shown in (b), one end is welded to the sixth electrode G6 so as to be in contact with the two intermediate electrodes Gm1 and Gm2 to obtain electrical conduction, and this is performed in the manufacturing process of the color picture tube described later. After the withstand voltage treatment, the coil shape is restored and the electrical connection between the sixth electrode G6 and the two intermediate electrodes Gm1 and Gm2 is released.

This color picture tube is manufactured as follows.

First, a phosphor screen is formed on the inner surface of the panel by a photo printing method. Then, a shadow mask is attached to the panel on which the phosphor screen is formed, and is joined (sealed) integrally with the funnel on which the inner conductive film is separately formed. Next, in the neck of the funnel,
As shown in (b), a shape memory alloy member 29 and a resistor were attached to the sixth electrode G6 so as to contact the two intermediate electrodes Gm1 and Gm2 to obtain electrical conduction. Seal the electron gun. Next, the color picture tube in which the resistor and the electron gun are sealed is heated and exhausted. Next, the getter is flushed in order to increase the degree of vacuum in the envelope, and the cathode is further activated, followed by withstanding voltage treatment.

As shown in FIG. 5, this withstand voltage treatment is performed by attaching the inner surface conductive film 23 applied to the sixth electrode G6 from the inner surface of the funnel to the inner surface adjacent to the neck 15 and the shield cup Cs. A high voltage of about 2 to 3 times the normal operating voltage is applied from the anode terminal 22 through the valve spacer 24 and the shield cup Cs that are in pressure contact with the membrane 23, and the cathodes KB, KG, KR (only KG is shown), the first , Second, third, fourth and fifth electrodes G1, G2,
This is done by grounding G3, G4, and G5 via a stem pin 21 implanted in the stem 20. In this case, since the sixth electrode G6 and the two intermediate electrodes Gm1 and Gm2 are electrically connected to the sixth electrode G6 by the contact of the shape memory alloy member 29, the intermediate electrodes Gm1 and Gm2 also have the above high voltage. Is applied. When a high voltage is applied to the intermediate electrodes Gm1 and Gm2 in this manner, the distance between the intermediate electrode Gm1 and the fifth electrode G5 is about 1 mm as described above, and the distance between the intermediate lens Gm1 and the fifth lens G5 is about 1 mm. Since the distance between the focusing electrode to be formed and the final accelerating electrode is almost the same, a sufficient spark can be generated between the intermediate electrode Gm1 and the fifth electrode G5.

After the withstand voltage treatment is further performed as described above, as shown in FIG. 6A, the shape memory alloy member 2 is formed.
9. A high-frequency induction heating coil 31 is arranged outside the neck 15 in which 9 is arranged, and the high-frequency induction heating coil 31 heats the shape memory alloy member 29 to a temperature higher than the temperature applied to the exhaust gas in the manufacturing process, As shown in (b), the coil shape is restored and the electrical connection between the two intermediate electrodes Gm1 and Gm2 and the sixth electrode G6 is released.

As described above, the anode high voltage applied to the intermediate electrodes Gm1 and Gm2 arranged between the fifth electrode G5 (focusing electrode) and the sixth electrode G6 (final accelerating electrode) forming the main lens portion. In the color picture tube which is divided and supplied by the resistor 7, the electric conduction is not released at a temperature equal to or lower than the temperature applied in the manufacturing process, but the electric conduction is released at a temperature higher than the temperature applied in the manufacturing process. When the sixth electrode G6 and the intermediate electrodes Gm1 and Gm2 are connected by using, a color picture tube is manufactured in the same manner as in the prior art, and then a high voltage necessary for the withstand voltage treatment is applied to the intermediate electrode Gm1 during the withstand voltage treatment. be able to. When a high voltage is applied to the intermediate electrode Gm1 in this manner, the distance between the intermediate electrode Gm1 and the fifth electrode G5 is such that the focusing electrode forming the main lens portion of the electron gun having no intermediate electrode and the final accelerating electrode. Since the distance is approximately the same as the distance, a sufficient spark can be generated between the intermediate electrode Gm1 and the fifth electrode G5 to remove foreign matters and burrs adhering to the electrode. After the withstand voltage treatment, the shape memory alloy member 29 is heated to a temperature higher than the temperature applied in the manufacturing process of the color picture tube,
By disconnecting the sixth electrode G6 and the intermediate electrodes Gm1 and Gm2 from each other, a color picture tube having a desired withstand voltage characteristic and not affecting other characteristics can be obtained.

In the above embodiment, the shape memory alloy member that restores the coil shape at the temperature applied in the manufacturing process of the color picture tube is attached to the sixth electrode, but this shape memory alloy member is essentially the color picture tube. Any shape that restores the electrical connection between the sixth electrode G6 and the intermediate electrodes Gm1 and Gm2 at a temperature equal to or higher than the temperature applied in the manufacturing process of (2), for example, as shown in FIG. Alternatively, it may be a shape memory alloy member 29 that is restored to a shape that is folded into two or more layers, or may be a shape memory alloy member 29 that is restored to a zigzag-shrinked shape as shown in FIG.

Further, in the above embodiment, the shape memory alloy member is welded to the sixth electrode and electrically connected to the two intermediate electrodes. However, this shape memory alloy member is used for any of the two intermediate electrodes. It may be welded to one of them.

Further, in the above embodiment, the electron gun in which the two intermediate electrodes are arranged in the main lens portion has been described. However, in the present invention, one or three or more intermediate electrodes are arranged in the main lens portion. It can also be applied to an electron gun.

Further, in the above embodiment, the electron gun for applying the dynamic focus voltage to the fifth electrode (focusing electrode) has been described. However, the present invention is applicable to other electron guns with a predetermined resistance through a resistor. It is applicable to all electron guns with electrodes supplied with voltage.

[0036]

The present invention has an electron beam generating portion composed of a cathode and a plurality of electrodes, and a main lens portion for focusing the electron beam from the electron beam generating portion on a phosphor screen. This main lens portion is the electron beam generating portion. From the electron gun consisting of a focusing electrode, one or more intermediate electrodes and a final accelerating electrode, which are sequentially arranged in the phosphor screen direction, and a high voltage supplied to the final accelerating electrode is divided to apply a predetermined voltage to the intermediate electrode. In the color picture tube in which the resistor to be supplied is arranged in the tube, the electrical continuity is not released at a temperature below the temperature at which the final accelerating electrode and the intermediate electrode are added in the manufacturing process of the color picture tube,
Electrical connection was made by a shape memory alloy member that restores a shape that releases electrical conduction at the temperature above, and this electrical connection was released to either one of the final acceleration electrode and the intermediate electrode. It is attached in a state of being restored to its shape, and the final accelerating electrode and the intermediate electrode are not released from electrical conduction below the temperature applied in the manufacturing process of the color picture tube, but restored to the shape released from electrical conduction above the above temperature. The electrical connection between the final accelerating electrode and the intermediate electrode is performed by electrically connecting with a shape memory alloy member and subjecting it to withstand voltage treatment, and after the withstand voltage treatment, heat the shape memory alloy member above the temperature applied in the manufacturing process of the color picture tube. When manufactured by the method of canceling the static conduction, the distance between the focusing electrode and the final accelerating electrode can be temporarily replaced with the distance between the focusing electrode and the intermediate electrode, and the resistance of the color picture tube during the manufacturing process can be improved. Sufficient sparks can be generated between the intermediate electrode and the focusing electrode during the pressure treatment, and the desired withstand voltage characteristics can be obtained by releasing the connection between the focusing electrode and the final acceleration electrode after the withstand voltage treatment. It can be a color picture tube.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of a color picture tube which is an embodiment of the present invention.

FIG. 2 is a diagram showing a configuration of an electron gun of the color picture tube and a relationship with a resistor.

FIG. 3A is a front view showing a cross section of the structure of the electron gun, and FIG. 3B is a side view showing the same cross section.

4 (a) and 4 (b) are views for explaining a shape change of a shape memory alloy member attached to the electron gun.

FIG. 5 is a diagram for explaining a withstand voltage processing method for the color picture tube.

FIGS. 6A and 6B are views for explaining a method of restoring the shape of the shape memory alloy member after the withstand voltage treatment.

7 (a) and 7 (b) are views showing the shapes of different shape memory alloy members.

8A is a diagram showing a horizontal deflection magnetic field generated by a deflection device of a self-convergence in-line type color picture tube, and FIG. 8B is a diagram showing a vertical deflection magnetic field.

FIG. 9 is a diagram showing a shape of a beam spot on a screen of a self-convergence in-line type color picture tube.

FIG. 10 (a) is a cross-sectional front view showing the configuration of an improved electron gun of a conventional self-convergence / in-line type color picture tube, and FIG. 10 (b) is a side view also showing the same. is there.

[Explanation of symbols]

 7 ... Resistor 12 ... Phosphor screen 15 ... Neck 16B, 16R ... Pair of side beams 16G ... Center beam 17 ... Electron gun 21 ... Stem pin 22 ... Anode terminal 23 ... Inner conductive film 29 ... Shape memory alloy member KB, KG, KR ... Cathode G1 ... First electrode G2 ... Second electrode G3 ... Third electrode G4 ... Fourth electrode G5 ... Fifth electrode G6 ... Sixth electrode Gm1, Gm2 ... Intermediate electrode

Claims (2)

[Claims] 1. An electron beam generating section comprising a cathode and a plurality of electrodes, and a main lens section for focusing the electron beam from the electron beam generating section on a phosphor screen, the main lens section generating the electron beam. Part of a focusing electrode, an electron gun including one or more intermediate electrodes and a final accelerating electrode, which are sequentially arranged in the phosphor screen direction, and a high voltage supplied to the final accelerating electrode is divided to a predetermined value for the intermediate electrode. In the color picture tube in which the resistor for supplying the voltage is arranged inside the tube, the final accelerating electrode and the intermediate electrode do not release electrical conduction at a temperature below the temperature applied in the manufacturing process of the color picture tube, and The shape memory alloy member is electrically connected by a shape memory alloy member that restores a shape that releases electrical conduction between the final accelerating electrode and the intermediate electrode at a temperature or higher. Color picture tube, characterized in that mounted in one of the states in which one to restore the shape releasing the electrical continuity of the final accelerating electrode and the intermediate electrode. 2. An electron beam generating section comprising a cathode and a plurality of electrodes, and a main lens section for focusing the electron beam from the electron beam generating section onto a phosphor screen, the main lens section generating the electron beam. Part of a focusing electrode, an electron gun including one or more intermediate electrodes and a final accelerating electrode, which are sequentially arranged in the phosphor screen direction, and a high voltage supplied to the final accelerating electrode is divided to a predetermined value for the intermediate electrode. In the method of manufacturing a color picture tube, the resistor for supplying the voltage is disposed inside the tube, and the electrical continuity is released below the temperature applied to the final acceleration electrode and the intermediate electrode in the manufacturing process of the color picture tube. First, the shape memory alloy member that is restored to a shape that releases electrical conduction at the temperature or higher is electrically connected and subjected to withstand voltage treatment, and after the withstand voltage treatment, the shape memory alloy member is Serial method for manufacturing a color picture tube is heated to a temperature higher than the temperature applied in the manufacturing process of the color picture tube, characterized in that to release the electrical connection between the final accelerating electrode and the intermediate electrode.