US3614500A - Misconvergence compensation for single-gun, plural-beam-type color tv picture tube - Google Patents

Misconvergence compensation for single-gun, plural-beam-type color tv picture tube Download PDF

Info

Publication number
US3614500A
US3614500A US815870A US3614500DA US3614500A US 3614500 A US3614500 A US 3614500A US 815870 A US815870 A US 815870A US 3614500D A US3614500D A US 3614500DA US 3614500 A US3614500 A US 3614500A
Authority
US
United States
Prior art keywords
beams
gun
axis
plural
convergence
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 - Lifetime
Application number
US815870A
Other languages
English (en)
Inventor
Senri Miyaoka
Minoru Morio
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Sony Corp
Original Assignee
Sony Corp
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Sony Corp filed Critical Sony Corp
Application granted granted Critical
Publication of US3614500A publication Critical patent/US3614500A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J31/00—Cathode ray tubes; Electron beam tubes
    • H01J31/08—Cathode ray tubes; Electron beam tubes having a screen on or from which an image or pattern is formed, picked up, converted, or stored
    • H01J31/10—Image or pattern display tubes, i.e. having electrical input and optical output; Flying-spot tubes for scanning purposes
    • H01J31/20—Image or pattern display tubes, i.e. having electrical input and optical output; Flying-spot tubes for scanning purposes for displaying images or patterns in two or more colours
    • H01J31/201—Image or pattern display tubes, i.e. having electrical input and optical output; Flying-spot tubes for scanning purposes for displaying images or patterns in two or more colours using a colour-selection electrode
    • H01J31/203—Image or pattern display tubes, i.e. having electrical input and optical output; Flying-spot tubes for scanning purposes for displaying images or patterns in two or more colours using a colour-selection electrode with more than one electron beam
    • H01J31/206—Image or pattern display tubes, i.e. having electrical input and optical output; Flying-spot tubes for scanning purposes for displaying images or patterns in two or more colours using a colour-selection electrode with more than one electron beam with three coplanar electron beams
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B82—NANOTECHNOLOGY
    • B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
    • B82Y10/00—Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic

Definitions

  • Eslinger and Alvin Sinderbrand ABSTRACT A single-gun, plural-beam-type color television picture tube in which three electron beams representing different color signals are focused by a single lens, after which two of the beams diverge.
  • the two divergent beams are reconverge by convergence deflecting means so they will intersect with the third beam at a common point at a beam-selecting grid, from which point the beams again diverge to impinge on respective color phosphors which together represent a color picture element.
  • Misconvergence i.e., reconvergence of the two divergent beams to a point other than to the common point of intersection with the third beam, which arises from manufacturing inaccuracies such as the misorientation of the convergence deflecting means with respect to the single electron gun of the tube, or the misorientation of the aperture of the beam-generating means of the tube, is compensated for by the provision of convergence deflecting means which exerts upon at least one of the divergent beams an electric, or Coulomb, force which varies in its direction in accordance with the position at which the beam enters and passes through the convergence deflecting means.
  • variations in the direction of the electric force compensates for variations in the position at which the beam is introduced to eliminate the misconvergence which arises from the above-mentioned manufacturing inaccuracies.
  • This invention relates generally to color picture tubes of the single-gun, plural-beam type, and particularly to tubes of that type in which the plural beams are passed through the optical center of a common electron lens by which the beams are focused on the color phosphor screen of the tube.
  • a single-gun, plural-beam color picture tube exists, in which three different cathodes produce three different electron beams that respectively correspond to the three primary colors.
  • An example of such a tube is disclosed specifically in a copending U.S. application Ser. No. 697,414 filed Jan. 12, I968, Pat. No. 3,448,316 and having a common assignee herewith.
  • the cathodes in such a tube are arranged in a horizontal row, so that the three electron beams start out side by side. Shortly after leaving the gun, the three beam intersect at a common point in the center of a single electrostatic lens which serves to focus all three beams upon a color screen. However, after leaving the focusing lens, the three electron beams diverge.
  • the center beam continues in a central straight line, but the two beams on both sides diverge sidewardly, i.e., outwardly, away from the path of the central beam, and must therefore be reconverged by pairs of convergence deflection electrodes to which a convergence deflection voltage is applied.
  • This convergence causes all three beams to intersect at a common point where they pass through a beamselecting grid, after which they again diverge to impinge on the respective color phosphors constituting a color picture element on the color screen.
  • the pairs of convergence deflection electrodes in the picture tube shown and described in this copending application comprise plates which are disposed in parallel with each other. Since the electrodes, i.e., plates, are flat and parallelly disposed with respect to each other, the direction of the electric, or Coulomb, force applied to the electron beams is always at right angles to the surface of these plates. As a result, misconvergence, i.e., reconvergence of the two divergent beams to a point other than the common point of intersection with the third beam, can be prevented only if the plural beam (i.e., the beam comprising the three beams mentioned above) always is introduced into convergence deflection electrodes at a predetermined position.
  • the plural beam i.e., the beam comprising the three beams mentioned above
  • this predetermined position is deviated from by a shift of the beam with respect to the plates or by another discrepancy, which causes at least one of the two diverging beams to be displaced in a direction parallel to surface of the flat plates, misconvergence is produced, which is not corrected by suitably compensating for the shift or other discrepancy.
  • the manufacturing inaccuracies which may cause this misconvergence include misorientation of the convergence deflecting means with respect to the single electron gun or misorientation of the aperture of the beam-generating means in such a picture tube.
  • the present invention provides convergence-deflecting means which exerts upon at least one of the diverging beams an electric force whose direction varies with the position at which it enters the convergence deflecting means, whereby any variation in the position at which it enters is corrected, or compensated for, by a variation in the direction of the electric force which is applied to it, such being to correct for misconvergence which would otherwise result.
  • FIG. 1 is a horizontal sectional view schematically showing a single-gun, plural-beam color picture tube such as disclosed in the above-mentioned application;
  • FIG. 2 is a cross-sectional view, also schematic, taken along the line I-I in FIG. I, which illustrates the condition when there is no discrepancy in the position at which the electron beams enter the convergence-deflecting means;
  • FIG. 3 is a view identical to the one shown in FIG. 2 which illustrates the condition when there is a discrepancy in the position at which two of the electron beams enter the convergence-deflecting means;
  • FIG. 4 is another view identical to the one shown in FIG. 2 which illustrates the condition when there is a discrepancy in the position at which one of the electron beams enters the convergence-deflecting means;
  • FIG. 5 is a cross-sectional view, similar to the cross-sectional view of FIG. 2, also schematic, showing electron beam convergence deflecting means for use in a color picture tube identical to the one shown in FIG. 1 except wherein the electron beams are disposed within the tube in a delta formation;
  • FIG. 6 is a perspective view schematically showing an electron beam convergence deflecting means, constructed in accordance with the teachings of this invention, for a single-gun, plural-beam color picture tube such as shown in FIG. 1;
  • FIG. 7 is a cross-sectional view, taken along the line II-II in FIG. 6, which illustrates the condition when there is no discrepancy in the position at which the electron beams enter the convergence deflecting means;
  • FIG. 8 is a cross-sectional view, identical to the one shown in FIG. 7, which illustrates the condition when there is a discrepancy in the position at which two of the electron beams enter the convergence-deflecting means;
  • FIG. 9 is a cross-sectional view, identical to the view of FIG. 7, which illustrates the condition when the electron beams are disposed in a delta formation as they are in FIG. 5;
  • FIG. 10 is a view, identical to the one shown in FIG. 8, of electron beam convergence-deflecting means constructed in accordance with and illustrating another embodiment of this invention.
  • FIG. 11 is a view, similar to the one shown in FIG. 8, of still another electron beam convergence-deflecting means constructed in accordance with and illustrating still another embodiment of this invention.
  • FIG. I schematically shows a cross-sectional view of a single-gun, plural-beam color picture tube such as disclosed in the aforementioned copending US. application
  • a single electron gun A of such a color television picture tube comprises three cathodes K K and K, which produce the electron beams B B G and B respectively for the red, green and blue signals of such a tube.
  • Thesethree beams after leaving their respective cathodes, pass through respective apertures g g and g fonned in a first grid 6,.
  • the apertures of the grids G and G serve the conventional beam-forming function.
  • the grid G, and electrodes G cooperate to form a relatively weak auxiliary lens I. by which the parallel beams are made to converge at the optical center ofa main lens L formed by electrodes (3,, G, and G and which serves to focus all three beams upon the phosphor screen S on the faceplate of the tube.
  • center beam B continues in a straight line coincident with-the optical axis of the lens.
  • the beams B and B however, diverge away from the center beam B
  • convergence deflecting electrodes generally designated F are provided for the purpose of converging the outer beams to intersect at a common spot with the center beam so that all three beams pass through the same aperture between individual grid wires g, of the beam-selecting grid or mask 6,.
  • the beams again diverge so that the red signal beam B goes on to strike the red phosphor stripe S the blue signal beam B goes on to strike the blue phosphor strip 8,, and the green signal beam B goes on to strike the green phosphor stripe S of a common color television picture element.
  • the first grid G may receive a static potential of O to minus 400 volts, for example about minus 400 volts
  • the second grid G may receive a static potential of to 500 volts, for example about 500 volts
  • the center lens element G may receive a potential of 0 to 400 volts, for example about 400 volts.
  • the two outer lens elements G and G are connected to a potential V which is at or near the anode potential (13 to 20 kv.) of the tube.
  • the first grid G performs the intensity modulation function, and therefore also has a signal voltage applied thereto.
  • the voltage distributions between the respective electrodes and cathodes and the respective lengths and diameters thereof may be substantially identical with those of a unipotential-single-beam type electron gun which is constituted by a single cathode and first and second, single-apertured grids.
  • a voltage V is applied to the grid wires g of the beam-selecting grid G .
  • the electron beams are swept horizontally and vertically across screen S to produce the usual cathode-ray tube raster- In FIG. 1, the electron beams B,,, B and B are swept from one extremity of the screen S to its other extremity.
  • the horizontal and vertical deflections necessary to produce the picture raster are of course accomplished by conventional deflection yokes D mounted outside the neck N of the picture tube.
  • the electron beam convergence deflecting means F comprises outer electrodes or flat plates, 0 and Q, and inner electrodes or flat plates P and P which are spaced from each other and respectively spaced inwardly from the plates Q and Q.
  • the inner electrodes P and P are maintained at a higher potential then either of the outer electrodes Q and 0. Since the electrodes P and P are of the same potential, the green signal beam 8 is not deflected in passing therebetween.
  • the blue signal beam B passes between the outer electrode Q and the inner electrode P, while the red signal beam B passes between the outer electrode Q and the inner electrode P. Accordingly, the divergent beams B and B are deflected inwardly by electric, or Coulomb, forces E and B (see FIG.
  • the outer electrodes 0 and Q are provided with potential V It is sufficient that this potential V is lower than the anode voltage V,. by about 200-300 volts.
  • the convergence deflecting means F causes beams B,; B and B, to intersect at a common point on the beam-selecting grid G
  • the three beams can be made to intersect accurately at the abovementioned common point by adjusting the intensity of the electric forces E and E and by adjusting the potential V because both of the electric forces E and E are in the direction of the horizontal axis x-and are directed toward the beam B
  • the coaxially disposed convergence deflecting means F and the single electron gun A are misaligned because one is rotated, i.e., angularly displaced, out of proper position with respect to the other, because of manufacturing inaccuracies or the like, the electric forces E and E are prevented from being directed toward the beam 8,,- because, as can be seen in FIG.
  • the line a, along which beams B B and 3,, are arranged, is displaced from axis x by an angle 41. Consequently, beams B B and B, are at best converged in a line along the vertical axis y, meeting at right angles with the horizontal axis x and passing through the central axis B when forced to converge in the direction of the forces E and E. They are not converged at the above-mentioned common point.
  • the respective distances between beam B and axis x and between beam B and axis x gradually increases as the beams go through the convergence deflecting means F toward the beam-selecting grid 6,.
  • convergence deflecting electrodes F shown in FIGS. 2 and 3 cause deflection of the beams only in the direction of the horizontal axis x. They do not cause the beams to be deflected in the direction of the vertical axis y.
  • FIG. 4 is a cross-sectional view identical to the one shown in FIG. 3 but one in which the position of the beams, at entry and upon passing through the deflecting means F, is somewhat different then the position of the beams in FIG. 3.
  • beams B and B enter and pass through the deflecting means at a predetermined position along the horizontal axis x, but the beam B enters and passes through at a position on a line displaced by an angle a from the axis x, as shown in FIG. 3.
  • the deflecting means F can focus the beams 3 and B, respectively, but it cannot focus beam B This is because there is no component of electric force E in the direction of axis y to shift the beam 8,, in that direction.
  • FIG. 5 is a cross-sectional view, similar to FIG. 2, of electron beam convergence deflecting means for a single-gun, plural-beam color picture tube, such as disclosed in the aforementioned copending application, having arrays of beamemitting cathodes and color phosphor respectively disposed in a delta formation.
  • the common inner electrode P of the convergence deflecting means F may be in the form of a tube having a triangular, or deltoid, cross section which is coaxial with the optical axis of the focusing lens L, and which has three flat sides arranged parallel to the flat plates Q. Q' and O" which are spaced outwardly therefrom.
  • color screen 8 (reference being bad to FIG. I) has, in this case, delta arrays of color phosphor 8,, S and S and the tube has beam-selecting means 0,. and beam-generating means respectively provided with apertures and cathodes K K and K corresponding to said arrays.
  • beam B for example, is biased for some reason from its position on axis x to a position B',,-, because of a discrepancy in the position of apertures g and g for example, there is no possibility that the three electron beams B B and B will converge into the central line of the color picture tube because the electric force E has no component in a direction at right angles to the axis x,.
  • convergence deflecting means F which eliminates the aforementioned troublesome manufacturing requirements and which is designed to effectively correct for any discrepancy in the position at which the electron beams enter the convergence deflecting means and to insure that the plural beams are converged in the vicinity of the phosphor screen, for example at the beam-selecting grid.
  • FIGS. 6 to 3 illustrate one embodiment of a convergence deflecting means F constructed in accordance with the teachings of this invention for use in a single-gun, plural-beam color picture tube of the type shown in FIG. 1.
  • a color picture tube constructed in accordance with this invention, therefore, is either identical or similar to the tube shown in FIG. 1, except that the structure of the convergence deflecting means F is different.
  • This convergence deflecting means F consists of apair of cylindrical electrodes P and O which are coaxially disposed and have different radii respectively. In accordance with this construction, if the positions B B and B at which the electron beams B B and B enter the convergence-deflecting means are arranged at equal intervals along horizontal axis x as shown in FIG.
  • the beams B B and B are converged although they are not all in a line (beam 8,, being located at the position 8' on axis x, similar to its location in FIG. 4) because the beam B is deflected in almost the same manner as it is in FIG. '7 and beam B is displaced as described above.
  • FIG. 9 shows convergence-deflecting means identical in construction to the convergence means shown in FIGS. 6 to 8, but in this case it is used for converging electron beams that are disposed in a delta formation such as shown in FIG. 5.
  • the beams B B and B are introduced accurately, i.e., introduced so as to define apexes of an equilateral triangle, into the convergence-deflecting means F and if the electric forces E and E from plates P and Q are directed toward the center 0, as in the case shown in FIG. 5, the three electron beams converge.
  • FIG. Ill shows convergence-deflecting means constructed in accordance with the teachings of this invention and illustrating another embodiment of it. As shown in this figure, the electrodes P and Q respectively are notched, i.e., they have portions removed, along their sides.
  • the single electrode P of the convergence-deflecting means shown in FIGS. 6 through 8 is substituted for a pair of opposing, halfcylindrical electrodes Q and Q".
  • this electrode arrangement enables unnecessary portions of electrodes P and Q to be removed since the electron beams are not usually biased very far from horizontal axis x. This simplifies the apparatus.
  • this convergence-deflecting arrangement achieves the same effect as is achieved by the arrangement shown in the FIGS. 6 to 8.
  • FIG. 11 shows other convergence-deflecting means constructed in accordance with the teachings of this invention and illustrating still another embodiment of it.
  • the radial center point 0 of the electrodes P and Q are shifted respectively along axis 1: so that the electrodes are brought closer together.
  • the electrodes are somewhat flatter i.e., they have less curvature, than those shown in FIG. 10. Consequently, the electric forces E and E applied respectively to electron beams B and B have a larger component in the direction of the horizontal axis x as compared to the component they have in the direction of vertical axis y than they have in the embodiment shown in FIG. 10.
  • beam-selecting grid G may be a chromatrontype grid (i.e., a line grid), a shadow mask, an aperture grid, any other appropriate device.
  • a single-gun, plural-beam color picture tube which includes a color screen having in-line arrays of different color phosphors, beam-selecting means provided with apertures corresponding respectively to said arrays, beam-generating means for directing a central electron beam and two side electron beams from in-line sources toward said color screen for 7 impingement on respective phosphors of each array through the corresponding aperture, single lens means for focusing said electron beams on said color screen and having an optical center through which said beams all are passed with said central beam being coincident with the optical axis of said lens means and said side beams being angled with respect to the optical axis of said lens means so as to enter said lens means along paths that are convergent to said optical axis and to emerge from said lens means along paths that are divergent to said axis, and convergence-deflecting means interposed between said lens means and said beam-selecting means and being operative to deflect said side beams emerging along said divergent paths to converge them with said central beam at an
  • a single-gun, plural-beam color picture tube in which an individual set of said inner and outer electrodes is provided for each of said side beams, and said inner and outer electrodes of each set are half-cylindrical with different radii and are coaxial with said optical axis.
  • a single-gun, plural-beam color picture tube in which an individual set of said inner and outer electrodes is provided for each of said side beams, said inner and outer electrodes of each set are part-cylindrical with different radii and have axes that are offset from said optical axis in the direction away from the side of said optical axis at which the respective set of electrodes is disposed.

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Nanotechnology (AREA)
  • Physics & Mathematics (AREA)
  • Mathematical Physics (AREA)
  • Theoretical Computer Science (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Video Image Reproduction Devices For Color Tv Systems (AREA)
US815870A 1968-04-14 1969-04-14 Misconvergence compensation for single-gun, plural-beam-type color tv picture tube Expired - Lifetime US3614500A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2489768 1968-04-14

Publications (1)

Publication Number Publication Date
US3614500A true US3614500A (en) 1971-10-19

Family

ID=12150959

Family Applications (1)

Application Number Title Priority Date Filing Date
US815870A Expired - Lifetime US3614500A (en) 1968-04-14 1969-04-14 Misconvergence compensation for single-gun, plural-beam-type color tv picture tube

Country Status (5)

Country Link
US (1) US3614500A (enrdf_load_html_response)
DE (1) DE1918878B2 (enrdf_load_html_response)
FR (1) FR2006217A1 (enrdf_load_html_response)
GB (1) GB1241111A (enrdf_load_html_response)
NL (1) NL162787C (enrdf_load_html_response)

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2148588A (en) * 1932-07-16 1939-02-28 Rca Corp Cathode ray tube
US2197523A (en) * 1936-07-31 1940-04-16 Gen Electric Cathode ray tube
US2849646A (en) * 1953-02-24 1958-08-26 Rauland Corp Color convergence system
US2911563A (en) * 1957-04-24 1959-11-03 Westinghouse Electric Corp Electrostatic lens and deflection system
US3124790A (en) * 1959-01-30 1964-03-10 Kuehlxr
US3448316A (en) * 1967-01-14 1969-06-03 Sony Corp Cathode ray tube
US3462638A (en) * 1967-07-10 1969-08-19 Sony Corp Electron beam correction apparatus for color picture tube
US3497744A (en) * 1966-08-11 1970-02-24 Philips Corp Cathode-ray tube using a quadrupolar electrostatic lens to correct orthogonality errors

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2148588A (en) * 1932-07-16 1939-02-28 Rca Corp Cathode ray tube
US2197523A (en) * 1936-07-31 1940-04-16 Gen Electric Cathode ray tube
US2849646A (en) * 1953-02-24 1958-08-26 Rauland Corp Color convergence system
US2911563A (en) * 1957-04-24 1959-11-03 Westinghouse Electric Corp Electrostatic lens and deflection system
US3124790A (en) * 1959-01-30 1964-03-10 Kuehlxr
US3497744A (en) * 1966-08-11 1970-02-24 Philips Corp Cathode-ray tube using a quadrupolar electrostatic lens to correct orthogonality errors
US3448316A (en) * 1967-01-14 1969-06-03 Sony Corp Cathode ray tube
US3462638A (en) * 1967-07-10 1969-08-19 Sony Corp Electron beam correction apparatus for color picture tube

Also Published As

Publication number Publication date
NL162787B (nl) 1980-01-15
FR2006217A1 (enrdf_load_html_response) 1969-12-19
DE1918878A1 (de) 1969-11-06
NL162787C (nl) 1980-06-16
GB1241111A (en) 1971-07-28
NL6905723A (enrdf_load_html_response) 1969-10-16
DE1918878B2 (de) 1972-02-17

Similar Documents

Publication Publication Date Title
US6353282B1 (en) Color cathode ray tube having a low dynamic focus
US4935663A (en) Electron gun assembly for color cathode ray tube apparatus
US3548249A (en) Color cathode ray tube of the pluralbeam,single electron gun type
US5936337A (en) Color picture tube with reduced dynamic focus voltage
US3594600A (en) Convergence means for a plural beam color picture tube
US3363128A (en) Convergence system for a tricolor, three-gun television tube
US5162695A (en) Electron gun assembly for a color cathode ray tube
US3467881A (en) Color picture tube
US3651359A (en) Abberation correction of plurality of beams in color cathode ray tube
US5262702A (en) Color cathode-ray tube apparatus
US3755703A (en) Electron gun device for color tube
US3619686A (en) Color cathode-ray tube with in-line plural electron sources and central section of common grid protruding toward central source
EP0913851A2 (en) Color cathode ray tube apparatus
US4833365A (en) Electron gun structure for converging electron beams
KR930008494B1 (ko) 전자총 장치
USRE29895E (en) Convergence means for a plural beam color picture tube
US3603839A (en) Color television picture tube of the single electron gun type
US5905332A (en) Electron gun for color cathode ray tube
US3614500A (en) Misconvergence compensation for single-gun, plural-beam-type color tv picture tube
US3678329A (en) Cathode ray tube
US3883771A (en) Collinear electron gun system including accelerating grid having greater effective thickness for off axis beams
US3575625A (en) Color tube with convergence electrode mounting and connecting structure
US3778666A (en) Convergence deflecting device for single-gun, plural-beam color picture tube
US2890379A (en) Distortion correction in cathode-ray tubes
US2747134A (en) Dual focus cathode-ray tubes