CA1061851A - Color television tube assembly - Google Patents
Color television tube assemblyInfo
- Publication number
- CA1061851A CA1061851A CA244,135A CA244135A CA1061851A CA 1061851 A CA1061851 A CA 1061851A CA 244135 A CA244135 A CA 244135A CA 1061851 A CA1061851 A CA 1061851A
- Authority
- CA
- Canada
- Prior art keywords
- color television
- television tube
- electrode
- aperture
- electron
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
- H01J29/00—Details of cathode-ray tubes or of electron-beam tubes of the types covered by group H01J31/00
- H01J29/46—Arrangements of electrodes and associated parts for generating or controlling the ray or beam, e.g. electron-optical arrangement
- H01J29/48—Electron guns
- H01J29/51—Arrangements for controlling convergence of a plurality of beams by means of electric field only
Landscapes
- Video Image Reproduction Devices For Color Tv Systems (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE
A color television tube assembly in which the aperture of a control grid of each electron gun is made in the form of an ellipse with its major axis in line with the vertical direction and the lengths of the vertical and horizontal axes of the aperture or actionspace of an electron lens electrode are selected different from each other, whereby the beam spot at the center of the screen may be in the form of a vertically elongated ellipse while the beam spots at the horizontal and vertical edges of the screen are in the form of a horizontally elongated ellipse.
A color television tube assembly in which the aperture of a control grid of each electron gun is made in the form of an ellipse with its major axis in line with the vertical direction and the lengths of the vertical and horizontal axes of the aperture or actionspace of an electron lens electrode are selected different from each other, whereby the beam spot at the center of the screen may be in the form of a vertically elongated ellipse while the beam spots at the horizontal and vertical edges of the screen are in the form of a horizontally elongated ellipse.
Description
S~
BACKGROUND OF THE _ VENTION:
The present invention relates to an improvement of a color television tube assembly of the type comprising a color . ~
television tube with three in-line electron guns for producing ;.,~
three electron beams in the same horizontal plane, a horizontal deflection yoke mounted on the color television tube for pro-~- ducing the pincushion-like horizontal deflection magnetic field and a vertical deflection yoke mounted on the tube for - producing the barrel-like vertical deflection magnetic field.
The so-called self-convergence in-line electron gun ~ .
type color television tube in which the horizontal deflection f i magnetic field with the pincushion distortion and the vertical `:~
~, ` deflec~ion magnetic field with the barrel distortion are pro-, . . .
~ duced has an advantage that a dynamic convergence circuit may .:.:, be eliminated. However, the electron beam from each electron gun is distorted when it passes through the pincushion-x - ~
distorted horizontal deflection magnetic field and the barrel-distorted vertical deflection magnetic field so that the beam -, spot especially at the edge of the screen is distorted in the form of an ellipse. In general, the further the electron ''~
j beam is away from the axis of the tube, the more strongly the beam is deflected in the horizontal direction. Therefore, the '~ larger the horizontal deflection angle, the more the beam spot at the screen is elongated in the horizontal direction.
On the other hand, the closer the electron beam is to the axis ,~
-'. 1 of the tube, the more strongly the beam is deflected in the 5,"",'/ vertical direction. Therefore, the larger the vertical , '..:~
deflection angle, the more the beam spot at the screen is elongated in the horizontal direction. The larger the deflec-tion angle of a color television tube, the greater the beam , distortion or aberration becomes especially at the edge of the ~- screen.
~; , -, . ~- , . , .~ . . , Si SUMMARY OF THE INVENTION:
One of the objects of the present invention is there-fore to provide a color television tube assembly in which the beam distortion over the whole surface of the screen may be considerably corrected.
Another object of the present invention is to provide a color television tube assembly which produces the beam spot in the form of a vertically elongated ellipse at the center of ~i.
the screen while producing the beam spots in the form of a 10 ~ horizontally elongated ellipse at the edge of the screen.
- A further object of the present invention is to pro-vide a color television tube assembly in which the aperture of ` ~ a control grid of each electron gun is made in the form of an ellipse with its major axis in line with the vertical direc-tion, and the lengths of the vertical and horizontal axes of the aperture or action space of an electron lens electrode are selected different from each other, whereby the distortion ;. . .
` , due to the distortion of electric field of the electron beam ~
~ :~................................................................... . .
r,,.,~' which has an elliptical cross sectional configuration and passes said aperture and a crossover reaching the screen may be suppressed.
. , .
A further object of the present invention is to pro-vide a color televislon tube assembly in which a pre-focusing , lens may converge the electron beam more strongly in the horizontal direction than in the vertical direction so that - the beam distortion due to the difference between the diverg-,:
ing angles of the electron beam; that is the distortion or aberration due to the distortion of the electric field may be : . :
suppressed. `~
To the above and other ends, the present invention provides a color television tube assembly of the type com-.. :;
prising a color television tube with three in-line electron
BACKGROUND OF THE _ VENTION:
The present invention relates to an improvement of a color television tube assembly of the type comprising a color . ~
television tube with three in-line electron guns for producing ;.,~
three electron beams in the same horizontal plane, a horizontal deflection yoke mounted on the color television tube for pro-~- ducing the pincushion-like horizontal deflection magnetic field and a vertical deflection yoke mounted on the tube for - producing the barrel-like vertical deflection magnetic field.
The so-called self-convergence in-line electron gun ~ .
type color television tube in which the horizontal deflection f i magnetic field with the pincushion distortion and the vertical `:~
~, ` deflec~ion magnetic field with the barrel distortion are pro-, . . .
~ duced has an advantage that a dynamic convergence circuit may .:.:, be eliminated. However, the electron beam from each electron gun is distorted when it passes through the pincushion-x - ~
distorted horizontal deflection magnetic field and the barrel-distorted vertical deflection magnetic field so that the beam -, spot especially at the edge of the screen is distorted in the form of an ellipse. In general, the further the electron ''~
j beam is away from the axis of the tube, the more strongly the beam is deflected in the horizontal direction. Therefore, the '~ larger the horizontal deflection angle, the more the beam spot at the screen is elongated in the horizontal direction.
On the other hand, the closer the electron beam is to the axis ,~
-'. 1 of the tube, the more strongly the beam is deflected in the 5,"",'/ vertical direction. Therefore, the larger the vertical , '..:~
deflection angle, the more the beam spot at the screen is elongated in the horizontal direction. The larger the deflec-tion angle of a color television tube, the greater the beam , distortion or aberration becomes especially at the edge of the ~- screen.
~; , -, . ~- , . , .~ . . , Si SUMMARY OF THE INVENTION:
One of the objects of the present invention is there-fore to provide a color television tube assembly in which the beam distortion over the whole surface of the screen may be considerably corrected.
Another object of the present invention is to provide a color television tube assembly which produces the beam spot in the form of a vertically elongated ellipse at the center of ~i.
the screen while producing the beam spots in the form of a 10 ~ horizontally elongated ellipse at the edge of the screen.
- A further object of the present invention is to pro-vide a color television tube assembly in which the aperture of ` ~ a control grid of each electron gun is made in the form of an ellipse with its major axis in line with the vertical direc-tion, and the lengths of the vertical and horizontal axes of the aperture or action space of an electron lens electrode are selected different from each other, whereby the distortion ;. . .
` , due to the distortion of electric field of the electron beam ~
~ :~................................................................... . .
r,,.,~' which has an elliptical cross sectional configuration and passes said aperture and a crossover reaching the screen may be suppressed.
. , .
A further object of the present invention is to pro-vide a color televislon tube assembly in which a pre-focusing , lens may converge the electron beam more strongly in the horizontal direction than in the vertical direction so that - the beam distortion due to the difference between the diverg-,:
ing angles of the electron beam; that is the distortion or aberration due to the distortion of the electric field may be : . :
suppressed. `~
To the above and other ends, the present invention provides a color television tube assembly of the type com-.. :;
prising a color television tube with three in-line electron
-2-o~
guns for produciny three electron beams in a horizontal plane, a horizontal deflection yoke mounted on said color television tube for producing a pincushion-like horizontal deflection magnetic field, and a vertical deflection yoke mounted on said color television tube for producing a barrel-like vertical deflection magnetic field characterized in that the aperture of a control grid of each electron gun is made in the form of , -~ an ellipse with its major axis in line with the vertical direc-tion, and the length of the vertical axis of either the aper-ture or the action space of an electron lens electrode of said tube is selected to be greater than the length of the horizon-tal axis of said aperture or action space so that in operation a beam spot produced on a screen of said tube is in the form of a vertically elongated ellipse at the center of the screen and in the form of a horizontally elongated ellipse, at the ,..
horizontal and vertical edges of the screen.
~`. BRIEF DESCRIPTION OF THE DRAWING:
i`~ Fig. 1 is a view used for the explanation of the beam spot distortion at the screen of a conventional color television tube;
Fig. 2 is a graph used for the explanation of the beam distortion due to the self-convergence magnetic field;
Fig. 3 is a schematic view of the arrangement of in-line type electron guns;
~- Fig. 4 is a schematic view used for the explanation of the area or shape of the beam spot at the screen of the color television tube in accordance with the present invention;
Fig. 5 is a schematic sectional view of a first embodiment of the present invention;
Fig. 6 is a perspective view thereof;
Fig. 7 is a schematic sectional view of a second -, embodiment of the present invention;
~ .
.- -3-~,~
7~ ' l~ Sl Fig. 8 is a perspective view thereof;
Fig. 9 is a schematic sectional view of a third embodiment of the present invention;
Fig. 10 is a perspective view thereof;
Fig. ll is a schematic sectional view of a fourth embodiment of the present invention; and Fig. 12 is a perspective view thereof.
,~ DESCRIPTION OF THE PREFERRED EMBODIMENTS:
In the so-called self-convergence type color tele-"`~ 10 vision tube with three in-line electron guns, the horizontal ~ and vertical deflection systems are so arranged as to produce ;- the magnetic fields with the pincushion and barrel distortions, ~- respectively, in order to eliminate a dynamic convergence -~
i circuit. However, the cross section of each electron beam from each of three electron guns passing through the pincushion-~ like-distorted horizontal deflection magnetic field and the }~ ~ barrel-li~e-distorted vertical deflection magnetic field are ~~ distorted so that the beam spot area at the edge of the screen is distorted in the form of an ellipse as schematically shown i 20 in Fig. l.
~'.
; Next referring to Fig. 2, the electron beam aberra-' tions due to the self-convergence fields will be explained.
In the pincushion-like horizontal deflection field A, the further the electron beam is away from the axis of the tube, the more strongly it is deflected in the horizontal direction.
,~ Therefore, the greater the deflection angle, the more the :, ,.
-- cross section of the electron beam is elongated in the hori-zontal direction. On the other hand, in the barrel-like '-- vertical deflection field B, the closer the electron beam is to the axis of the tube, the more strongly the electron beam . :-is deflected in the vertical direction. Therefore, the greater the vertical deflection angle, the more the cross section of ,. ~. .
''.
. . ~ . . . ~ - .
10~ 51 the electron beam is decreased in the vertical direction, and is elongated in the horizontal direction. Further, the beam spot area at the corner of the screen is elongated in the diagonal direction of the screen. This beam area distortion or aberration is most remarkable at the edge of the screen of the color television tube with a larger deflection angle.
Fig. 3 shows the electron guns arranged in line.
When the aperture 2 of a control grid 1 is in the form of an ellipse with its major axis in line with the vertical direction of a screen 3, the electron beam passing through the crossover 5 between the control grid 1 and a shield or second grid 4 has an elliptical cross sectional configuration. The electron ~,:
beam is diverged after it has passed through the crossover 5.
With the elliptical aperture, the horizontal diverging angle ~ is greater than the vertical diverging angle. Therefore, the beam distortion in the horizontal direction becomes the greatest in an electron beam focusing lens and especially at a main lens 6. In Fig. 3, reference numeral 7 denotes cathodes arrayed in the horizontal direction; 8, a pre-focusing lens;
9, a first anode or third grid; and 10, a second anode or ... .
fourth grid.
Next some preferred embodiments of a color television tube in accordance with the present invention will be des-cribed. Briefly stated, in accordance with the present inven-tion, the aperture of the control grid is in the form of an ellipse with its major axis in line with the vertical direc-tion so that the beam spot at the screen may become in the form of an ellipse with its major axis in line with the vertical direction when the electron beam is not deflected.
The ratio between the major and minor axes is suitably selected so that the true circular beam spots may be produced - in the area midway between the center of the screen and its ' ., .
edge as shown schematically in Fig. 4. Even though elliptical beam spots are produced at the center and edge of the screen, the eccentricity of an ellipse is considerably smaller than that of the elliptical beam spots produced on the screen of the conventional color picture tube. Therefore, the beam distortion may be considerably improved as a whole.
First Embodiment, Figs. 5 and 6 In the first embodiment shown in Figs. 5 and 6, a . .~ .
shield grid 40 is drawn toward the control grid l so as to lO form a bulged portion 41 having a rectangular or elliptical cross sectional configuration. The horizontal dimension hx and vertical dimension hy of the action space 42 defined by ~;
~ the bulged portion 41 must satisfy the following relation:
`~ hx ~ hy With the shield grid 40 with the above construction, the pre-focusing lens 8 converges the electron beam more ` strongly in the horizontal direction than in the vertical direction so that the beam distortion due to the difference `-between the horizontal and vertical diverging angles; that is, 20 the beam distortion caused by the electric field distortion ~) . , x may be suppressed. However, it should be noted that when the ; ratio hy/hx is too great, the electric field is more distorted, ~; thus resulting in the further distortion of the electron beam.
i, .
.;, Second Embodiment, Figs. 7 and 8 , In the second embodiment shown in Figs. 7 and 8, two -- tongue-shaped conductors 92 and 93 are extended in parallel with each other from the major surface of the first anode 90 opposite to the major surface facing the shield grid 4, and are spaced apart from the aperture 91 of the first anode 90 ,::: - . .
by a suitable distance. The tongue-like conductors 92 and 93 ~'~ define an action space in which the intensity of the diverging ~-~ electric field 8a of the pre-focusing lens 8 may be made weaker ~ ,'.' .
,.. .
., .
. - . .
'` :1()~1~51 s~. , in the horizontal direction than in the vertical direction.
Therefore, the pre-focusing lens 8 converges the electron beam more strongly in the horizontal direction than in the vertical direction so that the beam distortion due to the distortion - of the electric field may be suppressed.
Third Embodiment, Figs. 9 and 10 The apertures 96 and 101 of a first anode 95 and a second anode 100 are made in the form of an ellipse with its major axis in line with each other and with the vertical direc-r 10 tion. Therefore, the main lens 6 converges the beam more strongly in the horizontal direction than in the vertical direction so that the beam distortion due to the distortion of ~' the electric field may be suppressed because ofthe same reason r, described above.
i Fourth Embodiment, Figs. 11 and 12 In the fourth embodiment shown in Figs. 11 and 12, an auxiliary electrode 80 is interposed between the shield grid ~- 4 and the first anode 9 so that the pre-focusing lens 8 may ~' converge the electron beam more strongly in the horizontal ~-~,~ 20 direction than in the vertical direction. The auxiliary electrode 80 consists of a bulged electrode 81 with the bulged portion directed toward the shield grid 4 and a flat electrode 82. A circular aperture 83 is formed through the bottom of the bulged portion of the bulged electrode 81, and the horizon- ~ -tal dimension hx and vertical dimension hy of an aperture 84 ~' of the flat electrode 82 satisfy the following xelation:
,~
-~ hxc hy.
~.~
~ ~ Therefore, as described above, the pre-focusing lens 8 con-, verges the beam more strongly in the horizontal direction than s~ ..;
~ 30 in the vertical direction so that the distortion of the :~ .
- ' electric field caused by the difference between the diverging angles and the beam distortion due to the distortion of the . .
'''' ,~
electric field may be suppressed.
In the fourth embodiment, about 300 to 500 volts may be impressed to the shield grid while about 3,000 to 6,000 ': volts may be impressed to both the first anode 9 and the ~:;` auxiliary electrode 80. The voltage impressed to the auxiliary ; : electrode 80 may be raised above or lowered below the voltage ~, .~` impressed to the first anode 9 so that the convergence of the electron beam by the pre-focusing lens in the horizontal or vertical direction may be suitably adjusted. Even when the first anode 9 and the auxiliary electrode 80 are interconnected : within or without the tube, the convergence of the beam by the . pre-focusing lens in both the horizontal and vertical direc-:~ tions may be suitably adjusted by the suitable adjustment of ~;
~-, the distance between the auxiliary electrode 80 and the shield -:
,. grid 4. . .-~,-'5 i :.
:' 20 ~;' 'ç:'', .
,.~,:;, ;
.;,, ", . .
., .' .. .. ~ .
:,.. :, , -: .
'.' ' .';` ' ~ 30 ".
::
~ :, ~: 8 .~ .
; '' ; .
,, -: :
guns for produciny three electron beams in a horizontal plane, a horizontal deflection yoke mounted on said color television tube for producing a pincushion-like horizontal deflection magnetic field, and a vertical deflection yoke mounted on said color television tube for producing a barrel-like vertical deflection magnetic field characterized in that the aperture of a control grid of each electron gun is made in the form of , -~ an ellipse with its major axis in line with the vertical direc-tion, and the length of the vertical axis of either the aper-ture or the action space of an electron lens electrode of said tube is selected to be greater than the length of the horizon-tal axis of said aperture or action space so that in operation a beam spot produced on a screen of said tube is in the form of a vertically elongated ellipse at the center of the screen and in the form of a horizontally elongated ellipse, at the ,..
horizontal and vertical edges of the screen.
~`. BRIEF DESCRIPTION OF THE DRAWING:
i`~ Fig. 1 is a view used for the explanation of the beam spot distortion at the screen of a conventional color television tube;
Fig. 2 is a graph used for the explanation of the beam distortion due to the self-convergence magnetic field;
Fig. 3 is a schematic view of the arrangement of in-line type electron guns;
~- Fig. 4 is a schematic view used for the explanation of the area or shape of the beam spot at the screen of the color television tube in accordance with the present invention;
Fig. 5 is a schematic sectional view of a first embodiment of the present invention;
Fig. 6 is a perspective view thereof;
Fig. 7 is a schematic sectional view of a second -, embodiment of the present invention;
~ .
.- -3-~,~
7~ ' l~ Sl Fig. 8 is a perspective view thereof;
Fig. 9 is a schematic sectional view of a third embodiment of the present invention;
Fig. 10 is a perspective view thereof;
Fig. ll is a schematic sectional view of a fourth embodiment of the present invention; and Fig. 12 is a perspective view thereof.
,~ DESCRIPTION OF THE PREFERRED EMBODIMENTS:
In the so-called self-convergence type color tele-"`~ 10 vision tube with three in-line electron guns, the horizontal ~ and vertical deflection systems are so arranged as to produce ;- the magnetic fields with the pincushion and barrel distortions, ~- respectively, in order to eliminate a dynamic convergence -~
i circuit. However, the cross section of each electron beam from each of three electron guns passing through the pincushion-~ like-distorted horizontal deflection magnetic field and the }~ ~ barrel-li~e-distorted vertical deflection magnetic field are ~~ distorted so that the beam spot area at the edge of the screen is distorted in the form of an ellipse as schematically shown i 20 in Fig. l.
~'.
; Next referring to Fig. 2, the electron beam aberra-' tions due to the self-convergence fields will be explained.
In the pincushion-like horizontal deflection field A, the further the electron beam is away from the axis of the tube, the more strongly it is deflected in the horizontal direction.
,~ Therefore, the greater the deflection angle, the more the :, ,.
-- cross section of the electron beam is elongated in the hori-zontal direction. On the other hand, in the barrel-like '-- vertical deflection field B, the closer the electron beam is to the axis of the tube, the more strongly the electron beam . :-is deflected in the vertical direction. Therefore, the greater the vertical deflection angle, the more the cross section of ,. ~. .
''.
. . ~ . . . ~ - .
10~ 51 the electron beam is decreased in the vertical direction, and is elongated in the horizontal direction. Further, the beam spot area at the corner of the screen is elongated in the diagonal direction of the screen. This beam area distortion or aberration is most remarkable at the edge of the screen of the color television tube with a larger deflection angle.
Fig. 3 shows the electron guns arranged in line.
When the aperture 2 of a control grid 1 is in the form of an ellipse with its major axis in line with the vertical direction of a screen 3, the electron beam passing through the crossover 5 between the control grid 1 and a shield or second grid 4 has an elliptical cross sectional configuration. The electron ~,:
beam is diverged after it has passed through the crossover 5.
With the elliptical aperture, the horizontal diverging angle ~ is greater than the vertical diverging angle. Therefore, the beam distortion in the horizontal direction becomes the greatest in an electron beam focusing lens and especially at a main lens 6. In Fig. 3, reference numeral 7 denotes cathodes arrayed in the horizontal direction; 8, a pre-focusing lens;
9, a first anode or third grid; and 10, a second anode or ... .
fourth grid.
Next some preferred embodiments of a color television tube in accordance with the present invention will be des-cribed. Briefly stated, in accordance with the present inven-tion, the aperture of the control grid is in the form of an ellipse with its major axis in line with the vertical direc-tion so that the beam spot at the screen may become in the form of an ellipse with its major axis in line with the vertical direction when the electron beam is not deflected.
The ratio between the major and minor axes is suitably selected so that the true circular beam spots may be produced - in the area midway between the center of the screen and its ' ., .
edge as shown schematically in Fig. 4. Even though elliptical beam spots are produced at the center and edge of the screen, the eccentricity of an ellipse is considerably smaller than that of the elliptical beam spots produced on the screen of the conventional color picture tube. Therefore, the beam distortion may be considerably improved as a whole.
First Embodiment, Figs. 5 and 6 In the first embodiment shown in Figs. 5 and 6, a . .~ .
shield grid 40 is drawn toward the control grid l so as to lO form a bulged portion 41 having a rectangular or elliptical cross sectional configuration. The horizontal dimension hx and vertical dimension hy of the action space 42 defined by ~;
~ the bulged portion 41 must satisfy the following relation:
`~ hx ~ hy With the shield grid 40 with the above construction, the pre-focusing lens 8 converges the electron beam more ` strongly in the horizontal direction than in the vertical direction so that the beam distortion due to the difference `-between the horizontal and vertical diverging angles; that is, 20 the beam distortion caused by the electric field distortion ~) . , x may be suppressed. However, it should be noted that when the ; ratio hy/hx is too great, the electric field is more distorted, ~; thus resulting in the further distortion of the electron beam.
i, .
.;, Second Embodiment, Figs. 7 and 8 , In the second embodiment shown in Figs. 7 and 8, two -- tongue-shaped conductors 92 and 93 are extended in parallel with each other from the major surface of the first anode 90 opposite to the major surface facing the shield grid 4, and are spaced apart from the aperture 91 of the first anode 90 ,::: - . .
by a suitable distance. The tongue-like conductors 92 and 93 ~'~ define an action space in which the intensity of the diverging ~-~ electric field 8a of the pre-focusing lens 8 may be made weaker ~ ,'.' .
,.. .
., .
. - . .
'` :1()~1~51 s~. , in the horizontal direction than in the vertical direction.
Therefore, the pre-focusing lens 8 converges the electron beam more strongly in the horizontal direction than in the vertical direction so that the beam distortion due to the distortion - of the electric field may be suppressed.
Third Embodiment, Figs. 9 and 10 The apertures 96 and 101 of a first anode 95 and a second anode 100 are made in the form of an ellipse with its major axis in line with each other and with the vertical direc-r 10 tion. Therefore, the main lens 6 converges the beam more strongly in the horizontal direction than in the vertical direction so that the beam distortion due to the distortion of ~' the electric field may be suppressed because ofthe same reason r, described above.
i Fourth Embodiment, Figs. 11 and 12 In the fourth embodiment shown in Figs. 11 and 12, an auxiliary electrode 80 is interposed between the shield grid ~- 4 and the first anode 9 so that the pre-focusing lens 8 may ~' converge the electron beam more strongly in the horizontal ~-~,~ 20 direction than in the vertical direction. The auxiliary electrode 80 consists of a bulged electrode 81 with the bulged portion directed toward the shield grid 4 and a flat electrode 82. A circular aperture 83 is formed through the bottom of the bulged portion of the bulged electrode 81, and the horizon- ~ -tal dimension hx and vertical dimension hy of an aperture 84 ~' of the flat electrode 82 satisfy the following xelation:
,~
-~ hxc hy.
~.~
~ ~ Therefore, as described above, the pre-focusing lens 8 con-, verges the beam more strongly in the horizontal direction than s~ ..;
~ 30 in the vertical direction so that the distortion of the :~ .
- ' electric field caused by the difference between the diverging angles and the beam distortion due to the distortion of the . .
'''' ,~
electric field may be suppressed.
In the fourth embodiment, about 300 to 500 volts may be impressed to the shield grid while about 3,000 to 6,000 ': volts may be impressed to both the first anode 9 and the ~:;` auxiliary electrode 80. The voltage impressed to the auxiliary ; : electrode 80 may be raised above or lowered below the voltage ~, .~` impressed to the first anode 9 so that the convergence of the electron beam by the pre-focusing lens in the horizontal or vertical direction may be suitably adjusted. Even when the first anode 9 and the auxiliary electrode 80 are interconnected : within or without the tube, the convergence of the beam by the . pre-focusing lens in both the horizontal and vertical direc-:~ tions may be suitably adjusted by the suitable adjustment of ~;
~-, the distance between the auxiliary electrode 80 and the shield -:
,. grid 4. . .-~,-'5 i :.
:' 20 ~;' 'ç:'', .
,.~,:;, ;
.;,, ", . .
., .' .. .. ~ .
:,.. :, , -: .
'.' ' .';` ' ~ 30 ".
::
~ :, ~: 8 .~ .
; '' ; .
,, -: :
Claims (6)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A color television tube assembly of the type comprising a color television tube with three in-line electron guns for producing three electron beams in a horizontal plane, a horizontal deflection yoke mounted on said color television tube for producing a pincushion-like horizontal deflection magnetic field, and a vertical deflection yoke mounted on said color television tube for producing a barrel-like vertical deflection magnetic field characterized in that the aperture of a control grid of each electron gun is made in the form of an ellipse with its major axis in line with the vertical direction, and the length of the vertical axis of either the aperture or the action space of an electron lens electrode of said tube is selected to be greater than the length of the horizontal axis of said aperture or action space so that in operation a beam spot produced on a screen of said tube is in the form of a vertically elongated ellipse at the center of the screen and in the form of a horizontally elongated ellipse, at the horizontal and vertical edges of the screen.
2. A color television tube assembly as set forth in claim 1 wherein said electron lens electrode is a shield grid which forms a pre-focusing lens in association with another electrode.
3. A color television tube assembly as set forth in claim 1 wherein said electron lens electrode is a first anode which forms a main lens in association with another electrode of said tube.
4. A color television tube assembly as set forth in claim 1 wherein said electron lens electrode comprises auxiliary electrode means interposed between a shield grid and a first anode of said tube.
5. A color television tube assembly as set forth in claim 4 wherein said auxiliary electrode means comprises an electrode having a circular aperture and an electrode having a rectangular aperture, said rectangular aperture having its longer sides extending in a vertical direction.
6. A color television tube assembly as set forth in claim 2 wherein said shield grid comprises a bulged portion which extends towards the control grid and has a rectangular or elliptical cross sectional configuration.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP50010772A JPS6020864B2 (en) | 1975-01-24 | 1975-01-24 | Color picture tube device |
| JP1390375A JPS5518021B2 (en) | 1975-01-31 | 1975-01-31 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1061851A true CA1061851A (en) | 1979-09-04 |
Family
ID=26346097
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA244,135A Expired CA1061851A (en) | 1975-01-24 | 1976-01-23 | Color television tube assembly |
Country Status (4)
| Country | Link |
|---|---|
| AU (1) | AU500216B2 (en) |
| CA (1) | CA1061851A (en) |
| DE (1) | DE2602521A1 (en) |
| GB (1) | GB1537070A (en) |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| NL175002C (en) * | 1977-11-24 | 1984-09-03 | Philips Nv | CATHODE JET TUBE WITH AT LEAST AN ELECTRON GUN. |
| US4234814A (en) * | 1978-09-25 | 1980-11-18 | Rca Corporation | Electron gun with astigmatic flare-reducing beam forming region |
| EP0014922A1 (en) * | 1979-02-22 | 1980-09-03 | International Standard Electric Corporation | Electron gun |
| JPS55136442A (en) * | 1979-04-10 | 1980-10-24 | Toshiba Corp | Electron gun |
| IT1214441B (en) * | 1981-07-10 | 1990-01-18 | Rca Corp | SYSTEM FOR THE VISUALIZATION OF COLOR IMAGES. |
| JPS59111237A (en) * | 1982-12-16 | 1984-06-27 | Matsushita Electronics Corp | Cathode ray tube device |
-
1976
- 1976-01-21 GB GB224776A patent/GB1537070A/en not_active Expired
- 1976-01-22 AU AU10505/76A patent/AU500216B2/en not_active Expired
- 1976-01-23 CA CA244,135A patent/CA1061851A/en not_active Expired
- 1976-01-23 DE DE19762602521 patent/DE2602521A1/en not_active Ceased
Also Published As
| Publication number | Publication date |
|---|---|
| AU1050576A (en) | 1977-07-28 |
| AU500216B2 (en) | 1979-05-17 |
| GB1537070A (en) | 1978-12-29 |
| DE2602521A1 (en) | 1976-07-29 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US4143293A (en) | In line electron guns for color tubes, each having a control grid with vertically elliptical aperture | |
| US4814670A (en) | Cathode ray tube apparatus having focusing grids with horizontally and vertically oblong through holes | |
| US5027042A (en) | Color display tube system with reduced spot growth | |
| US4415831A (en) | Electromagnetic deflection type picture tube device | |
| EP0302657B1 (en) | An electron gun structure for a colour picture tube apparatus | |
| US4701677A (en) | Color cathode ray tube apparatus | |
| USRE33592E (en) | Color display tube with reduced deflection defocussing | |
| US4057747A (en) | In-line plural beam color cathode ray tube having deflection defocus correcting elements | |
| EP0111872B1 (en) | Cathode ray tube apparatus | |
| US4701678A (en) | Electron gun system with dynamic focus and dynamic convergence | |
| US4728859A (en) | In-line electron gun | |
| JP2611942B2 (en) | Color display device and color cathode ray tube | |
| US4641058A (en) | Electron gun | |
| US3970890A (en) | Plural beam cathode ray tube including an astigmatic electron lens and self-converging | |
| US5128586A (en) | Color cathode ray tube gun having control grid of varying thickness | |
| CA1061851A (en) | Color television tube assembly | |
| US4988926A (en) | Color cathode ray tube system with reduced spot growth | |
| US4600858A (en) | Color cathode ray tube apparatus to modify deflection magnetic fields | |
| US5157301A (en) | Color cathode ray tube unit | |
| GB2099214A (en) | Colour display tube | |
| JPS6029183B2 (en) | deflection yoke | |
| US3883771A (en) | Collinear electron gun system including accelerating grid having greater effective thickness for off axis beams | |
| US6545403B1 (en) | Color cathode ray tube having a developed electron gun structure | |
| JP2636217B2 (en) | Color television display tube | |
| KR100291923B1 (en) | Electron gun for color cathode ray tube |