US3619687A - Color tv tube having curved convergence deflection plates - Google Patents

Color tv tube having curved convergence deflection plates Download PDF

Info

Publication number
US3619687A
US3619687A US813827A US3619687DA US3619687A US 3619687 A US3619687 A US 3619687A US 813827 A US813827 A US 813827A US 3619687D A US3619687D A US 3619687DA US 3619687 A US3619687 A US 3619687A
Authority
US
United States
Prior art keywords
beams
plates
screen
divergent
central beam
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
US813827A
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 US3619687A publication Critical patent/US3619687A/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

Definitions

  • Eslinger and Alvin Sinderbrand ABSTRACT In a color picture tube of the single-gun, pluralbeam type in which a central beam and two side beams originate in a common plane and are all made to pass through the center of an electron lens for focusing the beams on the color screen with the central beam emerging from the lens along the optical axis of the latter and the side beams emerging from the lens along paths that are oppositely divergent from the axis, the divergent side beams are acted upon by an electrostatic convergence deflecting device constituted by pairs of spaced plates arranged along the divergent paths and having voltages applied thereacross to produce electric fields by which the divergent side beams passing therethrough are deflected to converge at a common spot with the central beam on the apertured grill or mask associated fields the screen, and a main deflection yoke produces magnetic fields in the direction of the common plane of the beams and orthogonally thereto for causing the beams to scan the screen; the distances between the plates of each pair are varied in the direction perpendicular to
  • a convergence deflecting device Arranged along such divergent paths are respective pairs of convergence deflecting plates constituting a convergence deflecting device and having voltages applied thereacross to produce electric fields which laterally deflect the divergent beams in a substantially horizontal plane for causing all beams to converge at a common spot on the apertured beam-selecting grill or shadow mask associated with the color screen. Further, arranged between the convergence deflecting device and the screen is a main deflection yoke which, in response to its reception of horizontal and vertical sweep signals, produces horizontal and vertical magnetic deflection fields acting on all of the beams to cause the latter to scan the color screen in predetermined rasters.
  • the distances that the side beams travel through such field will be respectively greater and less than the distance that the central beam travels through the field when the beams are deflected toward one side or the other side of the screen. If the horizontal deflection field has a uniform flux density thereacross, the side beam traveling therethrough for the greater distance will be deflected to a greater extent than the side beam traveling the shorter distance through the field and misconvergence of the beams will result.
  • the rasters of the side beams may have shapes that are oppositely distorted with respect to the shape of the raster of the central beam.
  • Another object is to provide a single-gun, plural-beam color picture tube in which distortions of the rasters of the several beams are avoided by a particular construction of the convergence deflecting device.
  • the described distortions of the rasters of the side beams with respect to the raster of the central beam are avoided by suitably varying, in the direction perpendicular to the common plane in which the beams originate, the distances between the paired plates of the convergence deflecting device, whereby to correspondingly vary the strengths of the electric fields between such plates by which the side beams are convergently deflected.
  • FIG. l is a schematic sectional view in a horizontal plane passing through the axis of a single-gun, plural-beam color picture tube of the type to which this invention is preferably applied;
  • FIG. 2 is a diagrammatic view to which reference is hereinafter made in explaining the invention
  • FIG. 3 is a diagrammatic view showing the possible relative distortions of the rasters of the several beams, as seen from the viewers side of the tube screen, and which are to be avoided by this invention;
  • FIG. 4 is a diagrammatic, transverse sectional view through the convergence deflecting device of a color picture tube according to a first embodiment of this invention.
  • FIGS. 5-8 are views similar to FIG. 4, but showing other embodiments of the invention.
  • a single-gun, plural-beam color picture tube of the type to which this invention may be applied comprises a glass envelope (indicated in broken lines) having a neck N and cone C extending from the neck to a color screen S provided with the usual arrays of color phosphors S 8 and S and with an apertured beam selecting grill or shadow mask G Disposed within neck N is an electron gun A having cathodes K K and I(,,, each of which is constituted by a beam-generating source with the respective beamgenerating surfaces hereof disposed as shown in a plane which is substantially perpendicular to the axis of the electron gun A.
  • the beam-generating surfaces are arranged in a straight line so that the respective beams B B and B emitted therefrom are directed in a substantially horizontal plane containing the axis of the gun, with the central beam B being coincident with such axis.
  • a first grid G is spaced from the beam-generating surfaces of cathodes K K and K and has apertures g g and g formed therein in alignment with the respective cathode beam-generating surfaces.
  • a common grid G is spaced from the first grid G and has apertures g g and g formed therein in alignment with the respective apertures of the first grid 6,.
  • appropriate voltages are applied to the grids G and G and to the electrodes G G and G
  • a voltage of 0 to minus 400 v. is applied to the grid 6
  • a voltage of 0 to 500 v. is applied to the grid G
  • a voltage of 13 to 20k.v. is applied to the electrodes G and G
  • a voltage of 0 to 400 v. is applied to the electrode 6. with all of these voltages being based upon the cathode voltage as reference.
  • 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 beamtype electron gun which is constituted by a single cathode and first and second, single-apertured grids.
  • an electron lens field will be established between grid G and the electrode G to form an auxiliary lens L as indicated in dashed lines, and an electron lens field will be established around the axis of electrode G.,, by the electrodes G G and G to form a main lens L, again as indicated in dashed lines.
  • bias voltages of v., 0 v., 300 v. 20 k.v., Zilb v. and 20 v. may be applied respectively to the cathodes K K and K the first and second grids G and G and the electrodes 6,, G and G Further included in the electron gun A of FIG.
  • I are electron beam convergence deflecting means F which comprise inner shielding plates P and P disposed in the depicted spaced, relationship at opposite sides of the gun axis, and axially extending, deflector plates Q and Q which are disposed, as shown, in outwardly spaced, opposed relationship to shielding plates P and P, respectively.
  • deflector plates Q and Q may, alternatively, be somewhat curved or outwardly bowed, as is well knovm in the art.
  • the shielding plates P and P are equally charged and disposed so that the central electron beam B will pass substantially undeflected therebetween, while the deflector plates Q and Q have negative charges with respect to the plates P and P so that electron beams B and B will be convergently deflected as shown by the respective passages thereof between the plates P and Q and the plates P and Q. More specifically, a voltage V which is equal to the voltage applied to the electrode 6,, may be applied to both shielding plates P and P, and a voltage V which is some 200 to 300 v.
  • the electron beams B B G and B which emanate from the beam generating surfaces of the cathodes K K and K will pass through the respective grid apertures g and g to be intensity modulated with what may be termed the red, green, and blue, intensity modulation signals applied between the said cathodes and the first grid G
  • the electron beams will then pass through the common auxiliary lens L to cross each other at the center of the main lens L.
  • the central electron beams B will pass substantially undeflected between shielding plates P and P since the later are at the same potential. Passage of the electron beam B between the plates P and Q and of the electron beam B between the plates P and Q will, however, result in the convergent deflections thereof as a result of the convergence deflecting voltage V applied therebetween, the system of FIG 1 is so arranged that the electron beams B B and B will desirably converge or cross each other at a common spot centered in an aperture of the beam-selecting grill or mask G so as to diverge therefrom to strike the respective color phosphors of a corresponding array thereof on screen S.
  • the color phosphor screen S is composed of a large plurality of sets or arrays of vertically extending red, green and blue" phosphor stripes or dots S S and S with each of the arrays or sets of color phosphors forming a color picture element.
  • the common spot of beam convergence corresponds to one of the thusly fonned color picture elements.
  • the voltage V may also be applied to the lens electrodes G and G and to the screen S as an anode voltage as well as to the aperture grill G Electron beam scanning of the face of the color phosphor screen is effected in conventional manner, for example, main deflection yoke means indicated in broken lines at D and which receives horizontal and vertical sweep signals to produce horizontal and vertical deflection fields by which the beams are made to scan the screen for providing a color picture thereon.
  • the respective electron beams are each passed, for focusing, through the center of the main lens L of the electron gun A, the beam spots formed by impingement of the beams on the color phosphor screen S will be substantially free from the effects of coma and/or astigmatism of the same main lens, whereby improved color picture resolution will be provided.
  • plates P and P and plates 0 and Q are shown flat and parallel with each other so that the electric fields between plates P and Q and plates P and Q are substantially uniform thereacross,
  • the side beams B and E travel distances through such horizontal deflection field that are respectively greater than and smaller than the distance that the central beam 8,; travels through the horizontal deflection field.
  • the horizontal deflection field of yoke D deflects the beams toward the right side of the screen as viewed from the viewers side, the distances traveled by the beams B and B through the horizontal deflection field are respectively smaller than and greater than the distance that the central beam B travels through such field.
  • the raster of beam B and the raster of beam B would be displaced toward the left and toward the right, respectively, from the raster of the beam B as seen from the viewers side of the screen.
  • the horizontal deflection field of yoke D is given a nonuniform flux density thereacross, for example, a greater flux density at the sides than at the middle of the field, the described relative displacements of the rasters can be compensated for so long as the common plane of the beam is substantially horizontal, that is, so long as the beams are directed at the screen substantially midway between the top and bottom of the screen.
  • the horizontal deflection field of yoke D directs the beams toward one side or the other of the screen at a time when the vertical deflection field of yoke D deflects the beams vertically so that the common plane of the beams is substantially inclined from the horizontal to direct the beams toward a comer of the screen
  • the differences between the distances traveled by the beams through the horizontal deflection are further increased, as compared with the differences in the distances traveled through the field when the common plane of the beam is horizontal, so that even the mentioned nonuniform flux density across the horizontal deflection field of yoke D would be ineffective to avoid distortions of the rasters of beams B and 8,; relative to the raster of beam B
  • the raster of central beam B has a rectangular shape, as indicated at L on FIG.
  • the raster L of beam B is distorted in the sense that its sides are convex toward the right, while the raster L of beam B is oppositely distorted, that is, its sides are convex toward the left.
  • such distortions of the rasters of side beams B and E relative to the raster of central beam B are avoided by suitably varying, in the direction perpendicular to the common plane in which the beams originate, for example, in the vertical direction for tube of FIG. ll, the distances by which plates P and Q and plates P and Q are spaced from each other.
  • FIG. ll the distances by which plates P and Q and plates P and Q are spaced from each other.
  • plates P and P are made flat or planar while plates Q and Q are outwardly concave in the vertical direction or the direction across the plates, whereby the distances between plates P and Q and between plates P and Q are relatively small at the horizontal plane 211 containing the tube axis and such distances between the plates increase progressively in the direction of vertical plane 22 upwardly and downwardly from horizontal plane 21 in which the beams all originate.
  • convergence deflecting device F is disposed adjacent the main deflecting yoke D (FIG. I)
  • the vertical deflection field of yoke D will extend into device F, and thereby influence the vertical positions of the beams B B and B in passing through device F.
  • the vertical deflection field of yoke D will vertically displace beams B B and B either upwardly or downwardly from plane 21 within convergence deflection device F.
  • the effect described above may also be achieved by providing flat or planar outer plates and Q and outwardly convex inner plates P and P (FIG. or by providing outer plates 0 and O that are inwardly convex and inner plates P and P that are outwardly convex (HO. 7).
  • the distances between plates P and Q and between P and Q vary from a minimum at the horizontal plane passing through the tube axis to maximums at the upper and lower portions of the plates to conversely vary the strengths of the electrical fields between plates P and Q and plates P and 0. Since plates P and P are at equal potential there is no electric field established therebetween, and thus the varying distance between plates P and P in FIGS. 5 and '7 does not affect beam B; as the latter is vertically deflected.
  • the distortions of rasters L and L relative to raster L that are to be corrected are those shown on FIG. 3.
  • a situation may arise, for example, by reason of a particular configuration of the horizontal deflection field produced by yoke D, in which the raster of beam B has the shape indicated at L on H6. 3 while the raster of beam 8,, has the shape indicated at L in the latter case, the plates P and Q and the plates P and Q are shaped so that the distances therebetween are maximum at the horizontal plane containing the axis of the tube and decrease progressively therefrom in the vertical direction, that is, in the direction perpendicular to the common plane in which the beams originate.
  • plates P and P may be flat or planar and plates 0 and Q may be outwardly convex (H6. 6), or platen P and P may be inwardly convex and plates Q AND 0 may be outwardly convex (FlG. d).
  • the convergence deflection device F consists of only a single pair of plates P and Q or P and Q acting on each of the beams B and 8,, to deflect the respective beam in the direction for convergence with the central beam B
  • the invention can also be applied to color picture tubes, for example, as disclosed in the copending US. application Ser. No. 718,738, filed Apr.
  • each of the side beams B and 1B is successively acted upon by two pairs of deflecting plates, as aforesaid, one or the other of such pairs of plates, and preferably the pair of plates closest to the location of the main deflection yoke, is provided with a distance between the plates that varies in the direction perpendicular to the common plane in which the beams originate so as to avoid distortion of the raster of the respective beam in accordance with this invention.
  • a single-gun, plural-beam color picture tube comprising a color screen, beam-generating means directing a central electron beam and two side beams in a common horizontal plane toward said screen electron lens means defining a focusing field having a center through which the beams pass and by which the bundle of electrons in each of the beams are focused on said color screen with the central beam emerging from said lens along the optical axis of the latter and said two side beams emerging from said lens along paths that are oppositely divergent from said central beam, electrostatic convergence deflecting means a pair of horizontally spaced plates arranged along each of said divergent paths, said spaced plates of each pair being disposed at the inside and outside, respectively, of the side beam in the related divergent path and having voltages applied thereacross to produce an electric field by which the respective side beam passing therethrough is deflected horizontally to converge at a common spot with said central beam and the other of said side beams, and a main deflection yoke producing magnetic fields by which said beams are deflected
  • a single-gun, pluralbeam color picture tube according to claim l, in which the inner plate of each of said pairs which is closest to said central beam is flat and the other plate of the respective pair is convex at the side thereof facing toward said inner plate.
  • a single-gun, plural-beam color picture tube according to claim 11, in which the inner plate of each of said pairs which is closest to said central beam is convex at the side thereof facing toward the other plate of the respective pair, and said other plate is flat.
  • a single-gun, plural-beam color picture tube according to claim l, in which the plates of each of said pairs are convex at the sides thereof facing toward each other.

Landscapes

  • Video Image Reproduction Devices For Color Tv Systems (AREA)
US813827A 1968-04-14 1969-04-07 Color tv tube having curved convergence deflection plates Expired - Lifetime US3619687A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP43024592A JPS4813969B1 (enrdf_load_stackoverflow) 1968-04-14 1968-04-14

Publications (1)

Publication Number Publication Date
US3619687A true US3619687A (en) 1971-11-09

Family

ID=12142410

Family Applications (1)

Application Number Title Priority Date Filing Date
US813827A Expired - Lifetime US3619687A (en) 1968-04-14 1969-04-07 Color tv tube having curved convergence deflection plates

Country Status (6)

Country Link
US (1) US3619687A (enrdf_load_stackoverflow)
JP (1) JPS4813969B1 (enrdf_load_stackoverflow)
DE (1) DE1918913B2 (enrdf_load_stackoverflow)
FR (1) FR2006214A1 (enrdf_load_stackoverflow)
GB (1) GB1223969A (enrdf_load_stackoverflow)
NL (1) NL6905718A (enrdf_load_stackoverflow)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4528476A (en) * 1983-10-24 1985-07-09 Rca Corporation Cathode-ray tube having electron gun with three focus lenses
US4772826A (en) * 1986-06-26 1988-09-20 Rca Licensing Corporation Color display system

Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE567907C (de) * 1928-04-05 1933-01-13 Karl Berger Dipl Ing Vorrichtung zur Strahlabsperrung in Kathodenstrahl-Oszillographen
US2403239A (en) * 1941-08-16 1946-07-02 Rca Corp Target electrode for electron discharge tubes
US2834902A (en) * 1953-07-18 1958-05-13 Telefunken Gmbh Deflection system for cathode ray tubes
US3065295A (en) * 1958-12-24 1962-11-20 Gen Electric Electron beam system
US3358172A (en) * 1965-07-28 1967-12-12 M O Valve Co Ltd Cathode ray tube with means for splitting the electron beam into individually deflected and focused beams
US3402358A (en) * 1964-11-09 1968-09-17 Research Corp Neutral particle beam accelerator having transverse electrodes and steering means for the particle beam
US3432711A (en) * 1966-07-05 1969-03-11 Itt Hybrid deflection image dissector having concave deflection plates converging at horizontal edges of resolving apertures
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
US3467881A (en) * 1967-04-06 1969-09-16 Sony Corp 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 (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE567907C (de) * 1928-04-05 1933-01-13 Karl Berger Dipl Ing Vorrichtung zur Strahlabsperrung in Kathodenstrahl-Oszillographen
US2403239A (en) * 1941-08-16 1946-07-02 Rca Corp Target electrode for electron discharge tubes
US2834902A (en) * 1953-07-18 1958-05-13 Telefunken Gmbh Deflection system for cathode ray tubes
US3065295A (en) * 1958-12-24 1962-11-20 Gen Electric Electron beam system
US3402358A (en) * 1964-11-09 1968-09-17 Research Corp Neutral particle beam accelerator having transverse electrodes and steering means for the particle beam
US3358172A (en) * 1965-07-28 1967-12-12 M O Valve Co Ltd Cathode ray tube with means for splitting the electron beam into individually deflected and focused beams
US3432711A (en) * 1966-07-05 1969-03-11 Itt Hybrid deflection image dissector having concave deflection plates converging at horizontal edges of resolving apertures
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
US3467881A (en) * 1967-04-06 1969-09-16 Sony Corp Color picture tube
US3462638A (en) * 1967-07-10 1969-08-19 Sony Corp Electron beam correction apparatus for color picture tube

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4528476A (en) * 1983-10-24 1985-07-09 Rca Corporation Cathode-ray tube having electron gun with three focus lenses
US4772826A (en) * 1986-06-26 1988-09-20 Rca Licensing Corporation Color display system

Also Published As

Publication number Publication date
GB1223969A (en) 1971-03-03
DE1918913A1 (de) 1969-11-06
NL6905718A (enrdf_load_stackoverflow) 1969-10-16
DE1918913B2 (de) 1971-09-02
JPS4813969B1 (enrdf_load_stackoverflow) 1973-05-02
FR2006214A1 (enrdf_load_stackoverflow) 1969-12-19

Similar Documents

Publication Publication Date Title
US3448316A (en) Cathode ray tube
US3772554A (en) In-line electron gun
US3949262A (en) Cathode ray tube with compensation for beam landing spot distortion due to wide-angle beam deflection
US3548249A (en) Color cathode ray tube of the pluralbeam,single electron gun type
US4317065A (en) Color picture tube having an improved electron gun with expanded lenses
US4520292A (en) Cathode-ray tube having an asymmetric slot formed in a screen grid electrode of an inline electron gun
US3594600A (en) Convergence means for a plural beam color picture tube
US3970890A (en) Plural beam cathode ray tube including an astigmatic electron lens and self-converging
US3467881A (en) Color picture tube
US3651359A (en) Abberation correction of plurality of beams in color cathode ray tube
US3619686A (en) Color cathode-ray tube with in-line plural electron sources and central section of common grid protruding toward central source
US3755703A (en) Electron gun device for color tube
US3500114A (en) Convergence system for a color picture tube
US3778666A (en) Convergence deflecting device for single-gun, plural-beam color picture tube
US3696261A (en) Cathode ray tube with plural beams for each color element
USRE29895E (en) Convergence means for a plural beam color picture tube
US3579008A (en) Color tube having asymetrical electrostatic convergence correction system
US3883771A (en) Collinear electron gun system including accelerating grid having greater effective thickness for off axis beams
US3639796A (en) Color convergence system having elongated magnets perpendicular to plane of plural beams
US3619687A (en) Color tv tube having curved convergence deflection plates
US4608515A (en) Cathode-ray tube having a screen grid with asymmetric beam focusing means and refraction lens means formed therein
US2806163A (en) Triple gun for color television
US4845401A (en) Color cathode ray tube with deflection means
US2726348A (en) Multiple beam gun
US3678329A (en) Cathode ray tube