EP0275191A2 - Tube image couleur muni d'un canon à trois lentilles - Google Patents

Tube image couleur muni d'un canon à trois lentilles Download PDF

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Publication number
EP0275191A2
EP0275191A2 EP88300247A EP88300247A EP0275191A2 EP 0275191 A2 EP0275191 A2 EP 0275191A2 EP 88300247 A EP88300247 A EP 88300247A EP 88300247 A EP88300247 A EP 88300247A EP 0275191 A2 EP0275191 A2 EP 0275191A2
Authority
EP
European Patent Office
Prior art keywords
electrode
lens
potential
beams
tube
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.)
Granted
Application number
EP88300247A
Other languages
German (de)
English (en)
Other versions
EP0275191A3 (en
EP0275191B1 (fr
Inventor
David Arthur New
Loren Lee Maninger
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.)
RCA Licensing Corp
Original Assignee
RCA Licensing Corp
RCA 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
Priority claimed from GB878700792A external-priority patent/GB8700792D0/en
Priority claimed from GB878700793A external-priority patent/GB8700793D0/en
Priority claimed from US07/128,951 external-priority patent/US4764704A/en
Application filed by RCA Licensing Corp, RCA Corp filed Critical RCA Licensing Corp
Publication of EP0275191A2 publication Critical patent/EP0275191A2/fr
Publication of EP0275191A3 publication Critical patent/EP0275191A3/en
Application granted granted Critical
Publication of EP0275191B1 publication Critical patent/EP0275191B1/fr
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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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
    • H01J29/50—Electron guns two or more guns in a single vacuum space, e.g. for plural-ray tube
    • H01J29/503—Three or more guns, the axes of which lay in a common plane
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J2229/00—Details of cathode ray tubes or electron beam tubes
    • H01J2229/48—Electron guns
    • H01J2229/4844—Electron guns characterised by beam passing apertures or combinations
    • H01J2229/4848—Aperture shape as viewed along beam axis
    • H01J2229/4872—Aperture shape as viewed along beam axis circular
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J2229/00—Details of cathode ray tubes or electron beam tubes
    • H01J2229/48—Electron guns
    • H01J2229/4844—Electron guns characterised by beam passing apertures or combinations
    • H01J2229/4848—Aperture shape as viewed along beam axis
    • H01J2229/4896—Aperture shape as viewed along beam axis complex and not provided for

Definitions

  • the invention relates to a color cathode-ray tube having an electron gun with three electron lenses, and, more particularly, to a three-lens electron gun capable of providing asymmetrically-shaped electron beams of substantially constant current density.
  • FIGURE 1 shows a conventional rectangular color picture tube 10 having a glass envelope 11 comprising a rectangular faceplate panel 12 and a tubular neck 14 connected by a rectangular funnel 16.
  • the panel 12 comprises a viewing faceplate 18 and a peripheral flange or sidewall 20 which is sealed to the funnel 16 by a frit seal 21.
  • a mosaic three-color phosphor screen 22 is located on the inner surface of the faceplate 18.
  • the screen preferably is a line screen with the phosphor lines extending substantially perpendicular to the high frequency raster line scan of the tube (normal to the plane of the FIGURE 1). Alternatively, the screen could be a dot screen.
  • a multi-apertured color selection electrode or shadow mask 24 is removably mounted, by conventional means, in predetermined spaced relation to the screen 22.
  • An inline electron gun 26 shown schematically by dashed lines in FIGURE 1 , is centrally mounted within the neck 14 to generate and direct three electron beams 28 along initially coplanar beam paths through the mask 24 and toward the screen 22.
  • One type of electron gun that is conventional is a four grid bi-potential electron gun such as that shown in FIGURE 2 and described in U. S. Patent No. 4,620,133 issued to Morrell et al. on October 28, 1986.
  • the tube of FIGURE 1 is designed to be used with an external magnetic deflection yoke, such as yoke 30 located in the region of the funnel-to-neck junction.
  • yoke 30 When activated, the yoke 30 subjects the three beams 28 to magnetic fields which cause the beams to scan horizontally and vertically in a rectangular raster over the screen 22.
  • the initial plane of deflection (at zero deflection) is shown by the line P-P in FIGURE 1 at about the middle of the yoke 30. Because of fringe fields, the zone of deflection of the tube extends axially from the yoke 30 into the region of the gun 26. For simplicity, the actual curvature of the deflected beam paths in the deflection zone is not shown in FIGURE 1.
  • the yoke 30 provides an inhomogeneous magnetic field that has a strong pin­cushion-like vertical deflection magnetic field and a strong barrel-like horizontal deflection magnetic field, to converge the electron beams at the peripheral part of the screen 22.
  • the beams are subject to distortions and defocusing.
  • FIGURE 3 represents an electron beam spot for a single beam which is circular at the center of the screen and undergoes various types of distortions at the periphery of the screen 22. As shown in FIGURE 3, the beam spot becomes horizontally elongated when deflected along the horizontal axis.
  • the beam spot at the four corners of the screen comprises a combination of horizontally elongated portions and vertically elongated portion that form elliptically-shaped spots with halo-shaped elongations thereabout.
  • the resolution is degraded as the electron beam is deflected, and the non-uniform focusing, which cannot be neglected, presents a problem which must be addressed.
  • FIG. 4a herein shows an electron beam current density contour, at the center of the screen 22, for an electron beam produced by the beam forming region and the main lens of the electron gun shown in FIGURE 2.
  • the beam current of the electron gun is 4 milliamperes.
  • FIGURE 4a shows the beam current density contour within the main lens, L2, that is between the G3 and G4 electrodes of Fig. 2.
  • the electron beam at this location is horizontally elongated; however, the 50% beam current density portion is contained within the small elliptical center section of the beam which is circumscribed by the larger elliptical portions which represent the 5% and 1% beam current density profiles.
  • FIGURE 4c shows the electron beam current density contour of the electron beam deflected into the upper right hand corner of the screen. Some haloing occurs above and below the central portion of the beam.
  • FIGURE 5 depicts the paths of the electrons emerging from the beam forming region of the electron gun of FIGURE 2 for various beam currents.
  • the beam current is adjusted to 4 milliamperes, and a crossover point occurs at about 2.8 to 2.9 mm (110 to 115 mils) from the cathode located at the origin.
  • the electrons are concentrated in the center portion of the beam. This distribution of electrons produces the current density contour, at the screen, shown in FIGURE 4a.
  • FIGURE 5b when the beam current is decreased to 0.8 millampere, the crossover point is shifted to a location about 1.14 mm (45 mils) from the cathode. It is apparent that the divergence angle of the electron beam is somewhat less at an operating current of 0.8 milliampere than at an operating current of 4.0 milliamperes (FIGURE 5a).
  • FIGURE 5c at a beam current of 0.2 milliampere, the crossover point is located less than about 0.6 mm (25 mils) from the cathode, and the beam is virtually a laminar beam.
  • the advantage of that two-lens structure over prior bi-potential structures is that, unlike various types of prior bi-potential electron guns, such as that shown in FIGURE 2, which provide an astigmatic shape to the electron beam by means of the first grid, Koshigoe et al. have utilized the second and/or third grids as the first astigmatic lens.
  • the latter structure allegedly permits the astigmatic electron beam formed by the first astigmatic lens to be compensated for in the main astigmatic focus lens, to provide a substantially circular-shaped beam spot on a phosphor screen of a cathode ray tube.
  • the structure described in the Koshigoe et al. patent is also applied to a composite lens type electron gun having six grids and three separate electron lenses, such as that shown in FIGURE 6.
  • the first (prefocus) lens, L1 is formed between the second and third grids; the third, fourth, and fifth grids constitute a sub-lens, L2; and the fifth and sixth grids constitute a main lens, L3.
  • the first (prefocus) lens serves as the first astigmatic lens
  • the main lens serves as the second astigmatic lens.
  • the allegation is that the deflected beam spot in this electron gun is superior to that obtained in prior art electron guns.
  • the location of the crossover point is dependent upon the beam current of the electron gun.
  • the first asymmetric lens, L1 is formed in the region between the second and third grid electrodes, G2 and G3, respectively, the crossover point may occur either before or after lens L1, depending upon the electron beam current.
  • the crossover point occurs after the lens L1, closer to the G3 electrode.
  • the asymmetric effect of lens L1 is a function of beam current.
  • the asymmetric lens should be located beyond the crossover point, regardless of the operating beam current of the electron gun. Additionally, it is desirable to have a gun structure which provides beams of substantially constant current density, in both the horizontal and vertical directions, in the main lens.
  • the present invention provides an improvement in color picture tubes which include an electron gun for generating and directing three electron beams, a center beam and two side beams, along initially coplanar paths towards the screen of the tube.
  • the gun includes a plurality of spaced electrodes which provide a first lens including a beam forming region for providing substantially symmetrical beams to a second lens.
  • the second lens includes beam refraction means for refracting the electron beams, emerging off the axis from the first lens, toward the axis, and asymmetric beam-focusing means for providing asymmetrically shaped beams to a third lens.
  • the third lens is a low aberration main focusing lens for providing an asymmetrically shaped beam of substantially constant current density to the screen.
  • an electron gun 40 is shown as comprising three equally spaced coplanar cathodes 42 (one for each beam), a control grid 44 (G1), a screen grid 46 (G2), a third electrode 48 (G3), a fourth electrode 50 (G4), a fifth electrode 52 (G5), the G5 electrode including a portion G5 ⁇ identified as element 54, and a sixth electrode 56 (G6).
  • the electrodes are spaced in the order named from the cathodes and are attached to a pair of support rods (not shown).
  • the cathodes 42, the G1 electrodes 44, the G2 electrode 46 and a portion of the G3 electrode 48 facing the G2 electrode 46 comprise a beam forming region of the electron gun 40.
  • Another portion of the G3 electrode 48, the G4 electrode 50 and the G5 electrode 52 comprise a first asymmetric lens.
  • the portion 54 of the G5 ⁇ electrode and the G6 electrode 56 comprise a main focusing (or second asymmetric) lens.
  • Each cathode 42 comprises a cathode sleeve 58 closed at its forward end by a cap 60 having an end coating 62 of an electron emissive material thereon, as is known in the art.
  • Each cathode 42 is indirectly heated by a heater coil (not shown) positioned within the sleeve 58.
  • the G1 and G2 electrodes, 44 and 46 are two closely spaced substantially flat plates each having three pairs of inline apertures 64 and 66, respectively, therethrough.
  • the apertures 64 and 66 are centered with the cathode coating 62, to initiate three equally-spaced coplanar electron beams 28 (as shown in Figure 1) directed towards the screen 22.
  • the initial electron beam paths are substantially parallel, with the middle path coinciding with the central axis A-A of the electron gun.
  • the G3 electrode 48 includes a substantially flat outer plate portion 68 having three inline apertures 70 therethrough, which are aligned with the apertures 66 and 64 in the G2 and G1 electrodes 46 and 44, respectively.
  • the G3 electrode 48 also includes a pair of cup-shaped first and second portions 72 and 74, respectively, which are joined together at their open ends.
  • the first portion 72 has three inline apertures 76 formed through the bottom of the cup, which are aligned with the apertures 70 in the plate 68.
  • the second portion 74 of the G3 electrode has three apertures 78 formed through its bottom, which are aligned with the apertures 76 in the first portion 72. Extrusions 79 surround the apertures 78.
  • the plate portions 68 with its inline apertures 70 may be formed as an integral part of the first portion 72.
  • the G4 electrode 50 comprises a substantially flat plate having three inline apertures 80 formed therethrough, which are aligned with the apertures 78 in the G3 electrode.
  • the G5 electrode 52 is a deep-drawn cup-shaped member having three apertures 82, surrounded by extrusions 83, formed in the bottom end thereof.
  • the G5 ⁇ electrode 54 comprises a deep-drawn cup-shaped member having a recess 92, formed in the bottom end with three inline apertures 94 formed in the bottom surface thereof. Extrusions 95 surround the apertures 94.
  • the opposite open end of the G5 ⁇ electrode 54 is closed by a second plate portion 96 having three openings 98 formed therethrough, which are aligned with and cooperate with the openings 90 in the first plate portion 88 in a manner described below.
  • the G6 electrode 56 is a cup-shaped deep-drawn member having a large opening 100 at one end, through which all three electron beams pass, and an open end, which is attached to and closed by a plate member 102 that has three apertures 104 therethrough which are aligned with the apertures 94 in the G5 ⁇ electrode 54. Extrusions 105 surround the apertures 104.
  • the shape of the recess 92 in the G5 ⁇ electrode 54 is shown in FIGURE 9.
  • the recess 92 has a uniform vertical width at each of the electron beam paths, with rounded ends. Such a shape has been referred to as the "racetrack" shape.
  • the shape of the large aperture 100 in the G6 electrode 56 is shown in FIGURE 10.
  • the aperture 100 is vertically higher at the side electron beam paths than it is at the center beam path.
  • Such a shape has been referred to as the "dogbone” or “barbell” shape.
  • the first plate portion 88 of the G5 electrode 52 faces the second plate portion 96 of the G5 ⁇ electrode 54.
  • the apertures 90 in the first plate portion 88 of the G5 electrode 52 have extrusions, extending from the plate portion, that have been divided into two segments 106 and 108 for each aperture.
  • the apertures 98 in the second plate portion 96 of the G5 ⁇ electrode 54 also have extrusions, extending from the plate portion 96, that have been divided into two segments 110 and 112 for each aperture. As shown in FIGURE 11, the segments 106 and 108 are interleaved with the segments 110 and 112. These segments are used to create quadrupole lenses in the paths of each electron beam when different potentials are applied to the G5 and G5 ⁇ electrodes 52 and 54, respectively.
  • the electron gun is electrically connected as shown in FIGURE 6.
  • the cathode operates at about 150V
  • the G1 electrode is at ground potential
  • the G2 and G4 electrodes are electrically interconnected and operate within the range of about 300V to 1000V
  • the G3 and G5 electrodes also are electrically interconnected and operate at about 7kV
  • the G6 electrode operates at an anode potential of about 25 kV.
  • the first lens, L1 (FIGURE 6) provides a symmetrically-shaped high quality electron beam rather than an asymmetrically-shaped electron beam into the second lens, L2.
  • the beam has a large divergence angle of about 120 milliradians and an electron distribution as shown by the ray diagram in FIGURE 12.
  • the crossover for the electron beam, operating at about 4 ma, occurs at a distance of about 0.090 inch (2.3 mm) from the cathode.
  • the corresponding beam current density contour of one of the beams is shown in FIGURE 13. It can be seen that the present beam forming region does not introduce any appreciable asymmetry into the electron beam.
  • the second lens, L2 comprising the G4 electrode 50 and the adjacent portions of the G3 electrode 48 and the G5 electrode 52, constitutes an asymmetric lens which provides a horizontally-elongated electron beam which, within the third or main focus lens, L3, has the beam spot contour shown in FIGURE 14.
  • the substantially rectangular shape of the electron beam is produced by the rectangular apertures 80 formed through the G4 electrode 50. Since the vertical dimensions of the apertures 80 are less than the horizontal dimensions, and the adjacent G3 and G5 electrodes operate at a potential greater than the potential on the G4 electrode, there is stronger vertical focusing of the beams prior to entering the main lens, L3.
  • the potential on the G4 electrode 50 (and on the interconnected G2 electrode 46) refracts the electrons of the electron beams emerging off-axes from the beam-forming region toward the axes.
  • the main focus lens, L3, formed between the G5 ⁇ electrode 54 and the G6 electrode 56 also is a low aberration, asymmetric lens, which provides a vertically-elongated, or asymmetrically-shaped, electron beam spot at the center of the screen.
  • the resultant beam spot, shown in FIGURE 15a has a substantially gaussian current density contour.
  • deflection of the beam to the upper right corner of the screen causes substantial elongation of the central 50% region of the beam, with enlarged regions or halos of lower intensity surrounding the central region.
  • the deflected electron beam current density contour can be improved as shown in FIGURE 15c.
  • a second embodiment of the computer modeled electron gun 40 shown in FIGURES 7 and 8 is presented in TABLE II.
  • the beam-forming region of the electron gun of the second embodiment is identical to the beam-forming region of the first embodiment, and like numbers are used to designate like tube elements throughout the electron gun.
  • the electron gun 40 is electrically connected as shown in FIGURE 16.
  • the cathode operates at about 150V
  • the G1 electrod at ground potential and the G2 electrode at about 400V.
  • the G3 electrode is electrically interconnected to the G5 electrode and operates at about 7 kV
  • the G4 electrode is electrically interconnected to the G6 electrode which operates at an anode potential of about 25 kV.
  • the first lens, L1 (FIGURE 16) provides a symmetrically-shaped high quality electron beam into the second lens, L2. Since the beam-forming region of the second embodiment is identical to that of the first embodiment, FIGURES 12 and 13 also show, respectively, the electron distribution and beam current density contour for one of the electron beams therefrom.
  • the second electron lens, L2 comprising the G4 electrode 50 and the adjacent portions of the G3 electrode 48 and the G5 electrode 52, constitutes an asymmetric lens which provides a horizontally-elongated, elliptically-shaped electron beam which, within the third or main focus lens, L3, has the beam current density contour shown in FIGURE 17.
  • the elliptical shape of the beam is produced by the interaction of the rectangular apertures 80 in the G4 electrode 50 and voltage gradients in the second lens, L2.
  • FIGURE 18 shows the resultant beam current density contour of an electron beam at the center of the screen.
  • the horizontal dimension of the apertures 80 in the second embodiment is less than the vertical dimension, and the adjacent G3 and G5 electrodes operate at a potential less than the potential on the G4 electrode, weaker horizontal focusing of the beams occurs prior to entering the main lens, L3.
  • FIGURES 15a and 18 are similar and demonstrate that acceptable performance can be achieved utilizing either embodiment.
  • the electrical configuration shown in FIGURE 6 is preferred, because the anode potential is not introduced into the lower voltage region of the electron gun.
  • a primary advantage of the embodiments presented in TABLES I and II over prior six-electrode electron guns, such as that described in U.S. Pat. 4,641,058, is that the initial asymmetric lens, L2, is located beyond the electron beam crossover point. Accordingly, the asymmetric effect of lens, L2, on the beam spot size and current density contour on the screen is relatively independent of the beam current. Additionally, the present structures provide beams of substantially constant current density, in both the horizontal and vertical directions, in the main lens.
  • the embodiments described herein are exemplary of the invention and are not meant to be limiting.
  • the rectangular apertures of the second embodiment of the G4 electrode 50 can be replaced with apertures of other suitable geometric shapes, to provide an asymmetric second lens.
  • the focus voltage on the G3 and G5 electrodes can be selected to vary the strength of the electron lenses in the electron gun.

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  • Electrodes For Cathode-Ray Tubes (AREA)
EP88300247A 1987-01-14 1988-01-13 Tube image couleur muni d'un canon à trois lentilles Expired - Lifetime EP0275191B1 (fr)

Applications Claiming Priority (6)

Application Number Priority Date Filing Date Title
GB8700793 1987-01-14
GB8700792 1987-01-14
GB878700792A GB8700792D0 (en) 1987-01-14 1987-01-14 Qpf-xl gun design
GB878700793A GB8700793D0 (en) 1987-01-14 1987-01-14 Db-xl gun design
US128951 1987-12-04
US07/128,951 US4764704A (en) 1987-01-14 1987-12-04 Color cathode-ray tube having a three-lens electron gun

Publications (3)

Publication Number Publication Date
EP0275191A2 true EP0275191A2 (fr) 1988-07-20
EP0275191A3 EP0275191A3 (en) 1989-06-07
EP0275191B1 EP0275191B1 (fr) 1995-09-27

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EP88300247A Expired - Lifetime EP0275191B1 (fr) 1987-01-14 1988-01-13 Tube image couleur muni d'un canon à trois lentilles

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EP (1) EP0275191B1 (fr)
JP (1) JPH0748354B2 (fr)
DE (1) DE3854506T2 (fr)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0366245A2 (fr) * 1988-10-27 1990-05-02 RCA Thomson Licensing Corporation Système d'affichage en couleur et tube comportant un canon à électrons modulé sur deux électrodes
EP0452789A2 (fr) * 1990-04-16 1991-10-23 Thomson Consumer Electronics, Inc. Tube d'images couleurs avec un canon à électrons "inline" muni de moyens pour régler la focalisation
EP0646944A2 (fr) * 1993-09-30 1995-04-05 Kabushiki Kaisha Toshiba Dispositif de tube à rayons cathodiques couleurs
GB2294581A (en) * 1994-10-24 1996-05-01 Sony Corp Electron gun for a cathode ray tube

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US2884559A (en) * 1956-09-07 1959-04-28 Bell Telephone Labor Inc Electron lens systems
JPS54120581A (en) * 1978-03-13 1979-09-19 Toshiba Corp Electron gun for color picture tube of in-line type
JPS598246A (ja) * 1982-07-05 1984-01-17 Toshiba Corp 電子銃
EP0104674A1 (fr) * 1982-08-25 1984-04-04 Koninklijke Philips Electronics N.V. Tube-image couleur
US4620133A (en) * 1982-01-29 1986-10-28 Rca Corporation Color image display systems
EP0231964A1 (fr) * 1986-01-21 1987-08-12 Koninklijke Philips Electronics N.V. Tube image couleur muni de moyens réduisant la défocalisation due à la déflexion
JPH06174246A (ja) * 1991-03-29 1994-06-24 Matsushita Seiko Co Ltd 空気調和機のエアーカーテン装置

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JPS63158732A (ja) * 1986-12-22 1988-07-01 Toshiba Corp カラ−受像管装置

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US2884559A (en) * 1956-09-07 1959-04-28 Bell Telephone Labor Inc Electron lens systems
JPS54120581A (en) * 1978-03-13 1979-09-19 Toshiba Corp Electron gun for color picture tube of in-line type
US4620133A (en) * 1982-01-29 1986-10-28 Rca Corporation Color image display systems
JPS598246A (ja) * 1982-07-05 1984-01-17 Toshiba Corp 電子銃
EP0104674A1 (fr) * 1982-08-25 1984-04-04 Koninklijke Philips Electronics N.V. Tube-image couleur
EP0231964A1 (fr) * 1986-01-21 1987-08-12 Koninklijke Philips Electronics N.V. Tube image couleur muni de moyens réduisant la défocalisation due à la déflexion
JPH06174246A (ja) * 1991-03-29 1994-06-24 Matsushita Seiko Co Ltd 空気調和機のエアーカーテン装置

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PATENT ABSTRACTS OF JAPAN, vol. 3, no. 141 (E-153), 21st November 1979, page 151 E 153; & JP-A-54 120 581 (TOKYO SHIBAURA DENKI K.K.) 19-09-1979 *
PATENT ABSTRACTS OF JAPAN, vol. 8, no. 88, 21st April 1984, page 74 E 240; & JP-A-59 008 246 (TOKYO SHIBAURA DENKI K.K.) 17-01-1984 *
TOSHIBA REVIEW, no. 121, May - Jun 1979, S. TAKENAKA et al.: "New Hi-Fi Focus Electron Gun for Color Cathode-Ray Tube", pages 30 - 35 *

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0366245A2 (fr) * 1988-10-27 1990-05-02 RCA Thomson Licensing Corporation Système d'affichage en couleur et tube comportant un canon à électrons modulé sur deux électrodes
EP0366245A3 (en) * 1988-10-27 1990-10-17 Rca Licensing Corporation Color display system and tube having an electron gun with dual electrode modulation
EP0452789A2 (fr) * 1990-04-16 1991-10-23 Thomson Consumer Electronics, Inc. Tube d'images couleurs avec un canon à électrons "inline" muni de moyens pour régler la focalisation
EP0452789A3 (en) * 1990-04-16 1992-02-12 Thomson Consumer Electronics, Inc. Color picture tube having inline electron gun with focus adjustment means
TR25229A (tr) * 1990-04-16 1993-01-01 Thomson Consumer Electonics In ODAK AYARLAMA ARACI OLAN SIRALI ELEKTRON TABANCA- SINA SAHIP OLAN RENKLI RESIM TüPü.
EP0646944A2 (fr) * 1993-09-30 1995-04-05 Kabushiki Kaisha Toshiba Dispositif de tube à rayons cathodiques couleurs
EP0646944A3 (fr) * 1993-09-30 1996-11-27 Toshiba Kk Dispositif de tube à rayons cathodiques couleurs.
US5694004A (en) * 1993-09-30 1997-12-02 Kabushiki Kaisha Toshiba Color cathode ray tube apparatus
GB2294581A (en) * 1994-10-24 1996-05-01 Sony Corp Electron gun for a cathode ray tube
US5773925A (en) * 1994-10-24 1998-06-30 Sony Corporation Electron gun for a cathode ray tube
GB2294581B (en) * 1994-10-24 1998-07-15 Sony Corp Cathode ray tube and electron gun for a cathode ray tube

Also Published As

Publication number Publication date
DE3854506D1 (de) 1995-11-02
JPH0748354B2 (ja) 1995-05-24
EP0275191A3 (en) 1989-06-07
JPS63198241A (ja) 1988-08-16
DE3854506T2 (de) 1996-04-04
EP0275191B1 (fr) 1995-09-27

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