JPH08329862A - Color image receiving tube - Google Patents

Abstract

PURPOSE: To provide a color image receiving tube having simply adjustability for the resistance dividing proportion of a resistor which is to supply a voltage to a selected electrode of an electron gun. CONSTITUTION: A color image receiving tube includes an electron gun 26 and a resistance circuit 27 consisting of a plurality of terminal parts and resistance parts provided between the terminal parts and is equipped with a resistor which divides the high voltage supplied to one of the terminal parts by the resistance part and supplies the obtained voltage to at least one selected electrode of the electron gun from other terminal part. This resistance circuit 27 is structured so as to have a resistance part connected in series and a resistance part connected in parallel.

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 more particularly to a color picture tube in which a voltage divided by a resistor is supplied to selected electrodes of an electron gun.

[0002]

2. Description of the Related Art Generally, a color picture tube has an envelope composed of a panel and a funnel, and a three-electron beam emitted from an electron gun sealed in a neck of the funnel is horizontally generated by a deflector. Deflected by a vertical deflection magnetic field,
The phosphor screen formed on the inner surface of the panel is horizontally and vertically scanned through the shadow mask to form a structure for displaying a color image. In such a color picture tube, the electron gun is an in-line type electron gun that emits three electron beams arranged in a line passing through the same horizontal plane, and the three electron beams are generated by the deflecting device as shown in FIG.
By deflecting by the pincushion type horizontal deflection magnetic field 1H shown in Fig. 1 and the barrel type vertical deflection magnetic field 1V shown in Fig. 3B, the three electron beams are concentrated on the phosphor screen without the need for circuit correction means. The self-convergence in-line type color picture tube that can be used is currently the mainstream of the color picture tube.

However, this self-convergence in-line type color picture tube has a pincushion type horizontal deflection magnetic field 1H and a vertical deflection magnetic field 1V barrel type. As shown for electron beam 2B in b), three electron beams 2B, 2G
, 2R are subjected to deflection distortion in which the focusing in the horizontal direction (X-axis direction) is weakened and the focusing in the vertical direction (Y-axis direction) is strengthened. Therefore, as shown in FIG. 5, the beam spot 3c in the central portion of the screen is almost a perfect circle, whereas the beam spot 3p in the peripheral portion of the screen extends vertically in addition to the high-brightness core portion 4. There is a problem that the shape is accompanied by the halo portion 5 having a low brightness, and the resolution in 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 Laid-Open No. 64-38947 discloses an electron gun shown in FIG. This electron gun
Three cathodes KB, KG arranged in a line in the horizontal direction,
KR (only KG is shown), these cathodes KB, KG, K
Three heaters (not shown) for individually heating R, first to fourth electrodes G1 to G4 arranged in the phosphor screen direction in order from the cathodes KB, KG, and KR, first divided into two, 2nd 5th electrode G51, G52, 1st, 2nd
The intermediate electrodes Gm1, Gm2, the sixth electrode G6 and the sixth electrode
It comprises a shield cup CS attached to the end of the electrode G6 on the phosphor screen side.

Each electrode G1 to G4, G51, G of this electron gun
52, Gm1, Gm2 and G6 are integrally formed, and the electrodes G1 to G4, G51, G52, Gm1, Gm2 and G6 and the shield cup CS have three cathodes K arranged in a line.
Three circular electron beam passage holes are formed corresponding to B, KG and KR. In particular, the electron beam passage hole on the first fifth electrode G51 side of the second fifth electrode G52, the second fifth electrode G52
The electron beam passage hole of 52 on the side of the first intermediate electrode Gm1 and the electron beam passage hole of the sixth electrode G6 on the side of the second intermediate electrode Gm2 are each formed in a non-circular shape.

In this electron gun, the cathodes KB, KG, K
R and the first and second electrodes G1 and G2 form a triode for controlling the emission of the electron beam from the cathodes KB, KG and KR, and the third and fourth electrodes G3 and G4, the first and the second electrodes are formed. Second fifth electrodes G51, G52, first and second intermediate electrodes Gm1,
The Gm2 and the sixth electrode G6 form an electron lens unit for accelerating and focusing the electron beam from the triode. In particular, the first and second fifth electrodes G51 and G52, the first and second intermediate electrodes Gm1 and Gm2, and the sixth electrode G6 form a main lens unit for finally focusing the electron beam on the phosphor screen. It is formed. This main lens part has two first and second intermediate electrodes Gm between the second fifth electrode G52 and the sixth electrode G6.
Since 1 and Gm2 are arranged, they serve as an expansion lens, and also serve as the first fifth electrode G51 side of the second fifth electrode G52, the first intermediate electrode Gm1 side of the second fifth electrode G52, and the sixth Electrode G
Since the electron beam passage hole on the side of the second intermediate electrode Gm2 of 6 is a non-circular shape, the first and second fifth electrodes G51, G52
Between the second fifth electrode G52 and the first intermediate electrode Gm1 and between the second intermediate electrode Gm2 and the sixth electrode G6 in the horizontal and vertical directions with respect to the electron beam, respectively. First, second and third quadrupole lenses are formed.

A predetermined voltage is applied to the second fifth electrode G52 of the main lens portion through a stem pin implanted in the stem at the neck end, and the sixth electrode G6 (final acceleration electrode) is applied to the sixth electrode G6. , The anode high voltage supplied to the anode terminal provided on the funnel is applied, but the first fifth electrode G51 and the first and second intermediate electrodes Gm1 and Gm2 each have a neck along the electron gun. The resistor 7 arranged inside divides the anode high voltage supplied to the high voltage supply terminal portion A0 at one end thereof, and 28% of the anode high voltage is supplied from the intermediate terminal portions A3, A2 and A1, respectively. Voltages of 40% and 65% are supplied.

In such an electron gun, since the electron beam is focused by the gentle electric field formed in the main lens portion, the beam spot on the screen can be reduced. Moreover, by applying a dynamic focus voltage that changes in synchronization with the deflection magnetic field generated by the deflecting device to the second fifth electrode G52, the first and second fifth electrodes G51,
The strength of the first quadrupole lens formed between G52 and the second quadrupole lens formed between the second fifth electrode G52 and the first intermediate electrode Gm1 changes, and The shape of the beam spot can be improved.

However, in general, the lens action of a quadrupole lens largely changes due to a slight voltage change. Therefore, when a voltage divided by a resistor 7 is applied to the electrodes forming the quadrupole lens as in the electron gun described above. It is necessary to prevent the resistance division ratio of the resistor 7 from largely deviating from the design value, and if the resistance division ratio deviates from the design value, it is necessary to correct it.

This modification of the resistance division ratio is carried out, for example, at one end of the resistor 7 whose design value of the resistance division ratio is 28%, 40%, 65% as described above, as shown in FIG. 7 (a). Resistor section 9 between the high voltage supply terminal section A0 and the intermediate terminal section A1 of
The resistance value R1 of a is 350 MΩ, the resistance value R2 of the resistance portion 9b between the intermediate terminal portions A1 and A2 is 250 MΩ, and the intermediate terminal portion A.
The resistance value R3 of the resistance portion 9c between 2 and A3 is 100 MΩ, and the resistance value R4 of the resistance portion 9d between the intermediate terminal portion A3 and the ground connection terminal portion A4 at the other end is 300 MΩ. Part A3, A2, A1 30%, 4 respectively
In the case of 0% and 65%, in order to set the resistance division ratio at the intermediate terminal portion A3 to 28% of the design value, as shown in (b), the intermediate terminal portion A3 and the other end portion are The resistance portion 9d must be trimmed so that the resistance value R4 of the resistance portion 9d between it and the ground connection terminal portion A4 becomes 272 MΩ. However, if the resistor part 9d is trimmed as described above,
The resistance division ratio at the intermediate terminals A2 and A1 is 38
% And 64%, the change amounts ΔA2 and ΔA1 of the resistance division ratio in the intermediate terminal portions A2 and A1 change by ΔA2 = 2% and ΔA1 = 1%, respectively. Therefore, when trimming as above,
Further, it is necessary to correct the resistance division ratio at the intermediate terminal portions A2 and A1 to the original resistance division ratio. Further, the resistance portion 9 between the terminal portion A0 at one end and the intermediate terminal portion A1 is required.
The resistance portion 9b between a and the intermediate terminal portions A1 and A2 is trimmed so that the resistance division ratio at the intermediate terminal portions A2 and A1 is brought close to the design value.

That is, regarding the resistor 7 which requires an accurate resistance division ratio as described above, if the resistance value of a partial resistance portion is changed in order to correct the resistance division ratio at one terminal portion, another The resistance division ratio in the terminal portion changes. Therefore, in order to bring the resistance division ratio of the other terminal portion close to the design value, it is necessary to change the resistance value of the other resistance portion, and it is difficult to bring the resistance division ratio of each terminal portion close to the design value. Moreover, the adjustment work becomes extremely complicated.

[0012]

As described above, as means for improving the deterioration of resolution due to the deflection distortion of the self-convergence in-line type color picture tube, three cathodes in which the electron guns are arranged in a line in the horizontal direction, Three heaters for individually heating these cathodes, first to fourth electrodes arranged in the phosphor screen direction in order from the cathode, and 2.
It is composed of a divided first and second fifth electrode, two first and second intermediate electrodes, a sixth electrode and a shield cup attached to the end of the sixth electrode on the phosphor screen side. ,
The first and second fifth electrodes, the first and second intermediate electrodes, and the sixth electrode form a main lens portion, and the main lens portion is formed between the first and second fifth electrodes and the second electrode. First, second, and third quadrupole lenses are respectively formed between the fifth electrode and the first intermediate electrode and between the second intermediate electrode and the sixth electrode, and the electron gun is provided. A resistor arranged along the line divides the anode high voltage applied to the sixth electrode to
There is one in which a predetermined voltage is supplied to the fifth electrode and the first and second intermediate electrodes.

However, in general, the lens action of a quadrupole lens largely changes due to a slight voltage change. Therefore, when a voltage divided by a resistor is supplied to the electrodes forming the quadrupole lens as in the electron gun, It is necessary to prevent the resistance division ratio of the resistor from largely deviating from the design value.If the resistance division ratio exceeds the allowable range with respect to the design value, it is necessary to correct the resistance division ratio. .

However, in the correction of the resistance division ratio, for example, when the resistance value of a partial resistance portion is changed in order to correct the resistance division ratio at one terminal portion, the resistance division ratio at the other terminal portion changes, Furthermore, in order to bring the resistance division ratio of the other terminal section closer to the design value, it is necessary to change the resistance value of the other resistance section, and it is difficult to bring the resistance division ratio of each terminal section close to the design value. There is a problem that it becomes extremely complicated.

The present invention has been made to solve the above problems, and resistance division of a resistor for supplying a voltage divided to at least one electrode selected from a plurality of electrodes of an electron gun. An object of the present invention is to make it possible to easily obtain a color picture tube having excellent characteristics as a structure in which the ratio can be easily adjusted.

[0016]

An electron gun having a cathode and a plurality of electrodes for controlling emission of an electron beam from the cathode and for accelerating and focusing the emitted electron beam; a plurality of terminal portions; At least one electron gun having a resistance circuit including a resistance part provided between the terminal parts and dividing a high voltage supplied to one of the terminal parts by the resistance part and selecting an electron gun from the other terminal parts. In a color picture tube including a resistor for supplying a predetermined voltage to the electrode of, a resistor circuit of the resistor is formed in a structure having a resistor portion connected in series and a resistor portion connected in parallel.

Further, the structure is such that the terminal portion is provided in the middle of the one resistance portion connected in parallel.

[0018]

With the above configuration, even if the resistance value of the parallel resistance portions is adjusted to bring the resistance division ratio at the terminal portion where the parallel resistance portions are formed close to the design value, other terminals The change in the resistance division ratio in each section can be made smaller than that in a conventional resistor including only a series resistance section.

[0019]

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

FIG. 1 shows a color picture tube which is an embodiment of the present invention. This color picture tube has an envelope composed of a panel 20 and a funnel-shaped funnel 21.
A phosphor screen 22 formed of a stripe-shaped three-color phosphor layer that emits blue, green, and red light is formed on the inner surface of the, and a shadow mask 23 is arranged inside the phosphor screen 22 so as to face the phosphor screen 22. There is. On the other hand, in the neck 24 of the funnel 21, an electron gun 26 that emits three electron beams 25B, 25G, 25R (only 25G is shown) arranged in a row passing on the same horizontal plane is arranged. A container 27 is arranged. Then, the three electron beams 25B, 25G, 2 emitted from the electron gun 26 are
Deflection device 29 with 5R mounted on the outside of the funnel 21
By deflecting by the horizontal and vertical deflection magnetic fields generated by the above, and by scanning the phosphor screen 22 horizontally and vertically,
It has a structure for displaying a color image.

The electron gun 26 has a horizontal direction (X-axis direction).
Three cathodes KB, KG, KR (K
(Only G is shown), three heaters (not shown) for individually heating the cathodes KB, KG, KR, and the first to fourth cathodes KB, KG, KR, which are sequentially arranged in the direction of the phosphor screen 22. Electrodes G1 to G4, divided first and second fifth electrodes G51 and G52, two first and second intermediate electrodes Gm1 and Gm2, a sixth electrode G6 and a phosphor of the sixth electrode G6 It consists of a shield cup CS attached to the end of the screen 22, and these cathodes KB, KG, K
R, heater and electrodes G1 to G4, G51, G52, G
The m1, Gm2, and G6 are integrally fixed by a pair of insulating supports (not shown).

Each electrode G1 to G4, G5 of this electron gun 26
1, G52, Gm1, Gm2, G6 are formed in an integral structure,
These electrodes G1 to G4, G51, G52, Gm1, Gm2, G
6 and the shield cup CS are provided with three circular electron beam passage holes corresponding to the three cathodes KB, KG and KR arranged in a line. Especially the second fifth electrode G52
Electron beam passing hole on the side of the first fifth electrode G51, electron beam passing hole on the side of the first intermediate electrode Gm1 of the second fifth electrode G52, and electron on the side of the second intermediate electrode Gm2 of the sixth electrode G6. The beam passage hole is formed in a non-circular shape.

In this electron gun 26, the cathodes KB, KG
, KR and the first and second electrodes G1, G2 form a triode for controlling the emission of the electron beam from each of the cathodes KB, KG, KR, and the third, fourth electrodes G3, G4, first, The second fifth electrodes G51, G52, the first and second intermediate electrodes Gm1, Gm2, and the sixth electrode G6 form an electron lens unit that accelerates and focuses the electron beam from the triode.
In particular, the first and second fifth electrodes G51, G52, the first and second electrodes
The intermediate electrodes Gm1 and Gm2 and the sixth electrode G6 finally form the main lens portion for focusing the electron beam on the phosphor screen 22. This main lens part is
Since the first and second intermediate electrodes Gm1 and Gm2 are arranged between the electrode G52 and the sixth electrode G6, they serve as expansion lenses and the first fifth electrode G51 of the second fifth electrode G52. side,
The second fifth electrode G52 on the side of the first intermediate electrode Gm1 and the sixth
By making the electron beam passage hole on the second intermediate electrode Gm2 side of the electrode G6 non-circular, two fifth electrodes G51, G52
Between the second fifth electrode G52 and the first intermediate electrode Gm1 and between the second intermediate electrode Gm2 and the sixth electrode G6 in the horizontal and vertical directions with respect to the electron beam, respectively. First, second and third quadrupole lenses are formed.

A dynamic focus voltage that changes in synchronization with the deflection magnetic field generated by the deflecting device 29 is applied to the second fifth electrode G52 via the stem pin 32 implanted in the stem 31 at the neck end. Applied to the sixth electrode G6
On the (final acceleration electrode), an inner conductive film 34 formed by coating from the large-diameter portion 33 of the funnel 21 to the inner surface of the adjacent portion of the neck 24, a valve spacer 35 attached to the shield cup CS and pressed against the inner conductive film 34. The anode high voltage supplied to the anode terminal 36 (see FIG. 1) provided in the large-diameter portion 33 of the funnel 21 is applied to the first fifth electrode G51 (focusing electrode) and the 1st and 2nd
The intermediate electrodes Gm1 and Gm2 are supplied with 28%, 40% and 65% of the high anode voltage by dividing the high voltage of the anode by a resistor 27 arranged in the neck along the electron gun 26, respectively.

The resistor 27 has a resistance circuit formed on an insulating substrate, and the resistance circuit is supplied with an anode high voltage provided at one end of the insulating substrate, as shown in FIG. A high-voltage supply terminal A0, a ground connection terminal A4 provided at the other end, and three intermediate terminals A1, A2 provided between the high-voltage supply terminal A0 and the ground connection terminal A4, A3 and these terminal portions A0, A1, A
2, A3, A4 and a high resistance portion provided between the intermediate portion terminal portion A3 to the first fifth electrode, the intermediate portion terminal portion A2 to the first intermediate electrode Gm1, the intermediate portion. Terminal part A1
Serves as a terminal portion for supplying a voltage to the second intermediate electrode Gm2. Particularly in the resistor 27 of this example, the resistance circuit is composed of a series resistance part and a parallel resistance part.

That is, as shown in FIG. 2, the resistor portion 38a between the high voltage supply terminal portion A0 and the intermediate portion terminal portion A1.
(Resistance value R1) and the resistance portion 38 between the intermediate terminal portions A1 and A2
b (resistance value R2) is connected in series and the intermediate terminal A2
Between these and the ground connection terminal A4.
The resistor part 38 that directly connects 2 to the ground connection terminal part A4
c (resistance value R3) and the resistance portion 38d between the intermediate terminal portions A2 and A3 connected in series with the intermediate terminal portion A3 in between.
The resistance value R4 and the resistance portion 38e (resistance value R5) between the intermediate terminal portion A3 and the ground connection terminal portion A4 are connected in parallel. In this case, the intermediate terminal portion A
The resistor part 38 that directly connects 2 to the ground connection terminal part A4
The resistance value R3 of c and the intermediate terminal parts A2, A connected in parallel
It is preferable that the resistance value R4 and R5 of the resistance portion 38d between the three and the resistance portion 38e between the intermediate terminal portion A3 and the ground connection terminal portion A4 satisfy the relation of R3 << R4 + R5.

By the way, of the three intermediate terminal portions A1, A2, and A3 like the resistor 27, the ground connection terminal portion A4 side, which has a relatively small design tolerance due to the structure of the resistance circuit 38. When the resistance part of is connected in parallel and the terminal part A3 is provided in the middle of one of the connected resistance parts in parallel, when the deviation from the design value of the resistance division ratio at the intermediate terminal part A3 is corrected, It is possible to reduce the change in the resistance division ratio at the terminal portions A1 and A2. In particular, as described above, the resistance value R3 of the resistor portion 38c that directly connects the intermediate terminal portion A2 and the ground connection terminal portion A4, the intermediate terminal portions A2 and A3 connected in parallel, and the intermediate terminal portion A3 and the ground connection terminal portion. The resistance value R4 of the resistance portion 38e between A4 and
By setting R5 and R3 << R4 + R5, the change in the resistance division ratio at the other intermediate terminal portions A1 and A2 can be greatly reduced.

For example, as shown in FIG. 3 (a), the anode high voltage is divided into the anode high voltage from the intermediate terminal portions A3, A2, A1 to the first fifth electrode and the first and second intermediate electrodes, respectively. Of the resistances 38a, 38b, 38c, 38d and 38e for supplying voltages of 28%, 40% and 65% of
1, R2, R3, R4 and R5 are R1 = 350MΩ R2 = 250MΩ R3 = 500MΩ R4 = 500MΩ R5 = 1500MΩ, respectively, and the resistance division ratios at the intermediate terminal portions A3, A2 and A1 are 30%, 40% and 65%, respectively. %, The resistance portion 38e is trimmed to correct the resistance division ratio of 30% at the intermediate terminal portion A3 to 28%, and the resistance value of the resistance portion 38e is adjusted as shown in FIG. If R5 is set to R5 = 1239 MΩ, then the resistance division ratio at the intermediate terminal portion A2 is 39.3% and the resistance division ratio at the intermediate terminal portion A1 is 64.6%. ΔA
2 and ΔA1 can be made significantly smaller than ΔA2v = 0.7% ΔA1v = 0.4% and ΔA2 = 2% ΔA1 = 1% in the conventional resistor shown in FIG. it can.

Therefore, by configuring the resistor 27 as described above, the number of times the resistance division ratio is corrected can be reduced, and the resistance division ratio can be kept within the design tolerance in a short time. Moreover, thereby, the manufacturing cost of a resistor can be reduced.

In the above embodiment, regarding the electron gun having the first and second fifth electrodes divided into two and the two intermediate electrodes, the first fifth electrode (focusing electrode) and the second electrode
The case where the voltage divided by the resistor is supplied to each of the intermediate electrodes has been described.
For an electron gun having one focusing electrode and one or three or more intermediate electrodes without division, another electron gun having a different configuration, such as a case where a voltage divided by a resistor is supplied to the intermediate electrode, It can also be applied to a color picture tube that has.

[0031]

EFFECT OF THE INVENTION A cathode, an electron gun having a plurality of electrodes for controlling the emission of an electron beam from the cathode and for accelerating and focusing the emitted electron beam, a plurality of terminal portions and between these terminal portions. It has a resistance circuit composed of a provided resistance part, and divides a high voltage supplied to one of its terminal parts by the resistance circuit to determine at least one selected electrode of the electron gun from the other terminal part. In a color picture tube including a resistor for supplying a voltage of, a resistor circuit of the resistor has a structure having a resistor portion connected in series and a resistor portion connected in parallel, and is also connected in parallel. If the structure is such that the terminal portion is provided in the middle of the one resistance portion, the resistance value of the one resistance portion connected in parallel is corrected,
Even if the resistance division ratio at the terminals of this parallel-connected resistance section approaches the design value, the change in the resistance division ratio at the other terminals is smaller than that of a conventional resistor consisting of only a series resistance section. can do. Therefore, by configuring the resistor as described above, the number of times the resistance division ratio is corrected can be reduced, and the resistance division ratio can be kept within the design tolerance in a short time. Moreover, thereby, the manufacturing cost of a resistor can be reduced.

[Brief description of drawings]

FIG. 1A is a diagram showing a configuration of a color picture tube which is an embodiment of the present invention, and FIG. 1B is a diagram showing a relationship between an electron gun and a resistor.

FIG. 2 is a diagram showing a configuration of a resistor of the color picture tube.

3A and 3B are diagrams for explaining adjustment of a resistance division ratio of the resistor.

FIG. 4 (a) is a diagram showing a pincushion type deflection magnetic field generated by a deflection device attached to a self-convergence in-line type color picture tube, and FIG. 4 (b) is a barrel type vertical deflection magnetic field. It is a figure.

FIG. 5 is a diagram showing a shape of a beam spot on a screen of the self-convergence in-line type color picture tube.

FIG. 6 is a diagram showing a relationship between an electron gun and a resistor of a conventional color picture tube.

7A and 7B are views for explaining adjustment of a resistance division ratio of a resistor of the conventional color picture tube, respectively.

[Explanation of symbols]

 22 ... Phosphor screen 26 ... Electron gun 27 ... Resistors 38a, 38b, 38c, 38d, 38e ... Resistor part A0 ... High voltage supply terminal parts A1, A2, A3 ... Intermediate terminal part A4 ... Ground connection terminal part Cs ... Shield Cup G1 ... First electrode G2 ... Second electrode G3 ... Third electrode G4 ... Fourth electrode G51 ... First fifth electrode G52 ... Second fifth electrode G6 ... Sixth electrode Gm1 ... First intermediate electrode Gm2 … Second intermediate electrode KG… Cathode

Claims (2)

[Claims] 1. An electron gun having a cathode and a plurality of electrodes for controlling the emission of an electron beam from the cathode and for accelerating and focusing the emitted electron beam, a plurality of terminal portions, and between each terminal portion. At least one electrode of the electron gun, which has a resistance circuit including a provided resistance section, divides a high voltage supplied to one of the terminal sections by the resistance section, and from another terminal section. In a color picture tube including a resistor for supplying a predetermined voltage to the resistor, the resistor circuit of the resistor is formed in a structure having a resistor portion connected in series and a resistor portion connected in parallel. Characteristic color picture tube. 2. The color picture tube according to claim 1, wherein a terminal portion is provided in the middle of one of the resistance portions connected in parallel.