US2689922A - Multigun cathode-ray tube - Google Patents

Multigun cathode-ray tube Download PDF

Info

Publication number
US2689922A
US2689922A US320271A US32027152A US2689922A US 2689922 A US2689922 A US 2689922A US 320271 A US320271 A US 320271A US 32027152 A US32027152 A US 32027152A US 2689922 A US2689922 A US 2689922A
Authority
US
United States
Prior art keywords
cathode
ray tube
guns
electron
magnetic
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
US320271A
Other languages
English (en)
Inventor
Francken Jan Carel
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.)
Hartford National Bank and Trust Co
Original Assignee
Hartford National Bank and Trust Co
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 Hartford National Bank and Trust Co filed Critical Hartford National Bank and Trust Co
Application granted granted Critical
Publication of US2689922A publication Critical patent/US2689922A/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
    • 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
    • H01J29/70—Arrangements for deflecting ray or beam
    • H01J29/701—Systems for correcting deviation or convergence of a plurality of beams by means of magnetic fields at least

Definitions

  • This invention relates to cathode-ray tubes
  • multi-gun cathode-ray tubes for color television reception or for the simultaneous recording of two or more values.
  • One form of color television system commonly employed utilizes three distinct electron guns located in the neck of a cathode-ray tube.
  • the television signal for exciting such a tube is generally broken down into separate channels for the red, green and blue components "of the color image, each of the colors energizing one of the electron guns.
  • the picture on the fluorescent screen at one end of the cathode-ray tube is built up by a composite of these three primary color pictures.
  • These systems usually also employ an apertured grid located in front of the luminescent screen in a position to intercept the electron beams in order to direct the beams at particular areas or points of the luminescent screen, the electron beam of each of the electron guns being required to pass through a.
  • the main object of the invention is to provide a simple apparatus, externally mounted on a multi-gun cathode-ray tube, for directing and/or foscussing the individual beams of the guns so that they impinge upon a luminescent screen at about the same point without requiring great care in the manufacturing or positioning of the guns themselves.
  • a cathode-ray tube comprising a luminescent screen supported at one end thereof and including a neck portion located at the opposite end is provided with a plurality of distinct electron guns.
  • Each of the electron guns is housed ina separate cylindrical tube, the tubes being arranged substantially parallel to one another and being connected to the neck portion of the tube. Focussing and directioning of the beams of the electron guns is effected by providing a magnetic device constituted by a pair of plane, substantially parallel plates of magnetic material having apertures therein for mounting said device on the cylindrical tubes housing the electron guns. Hollow slideable pole-members are provided in each of the apertures of one of the plates and surrounding the cylindrical tubes of the electron guns for individual focussing of the guns.
  • the arrangement according to the invention has the advantage that the space occupied thereby is materially smaller than that occupied by the previously-known arrangements. Moreover, accurate focussing and directioning of the beams is obtained in a very simple manner thereby eliminating the need for careful manufacturing and positioning of the guns.
  • Fig. 1 shows a cathode-ray tube according to the invention for reproducing color television images
  • Fig. 2 is a longitudinal section of a magnetic system of poles according to the invention for simultaneous production of the focussing fields in a multi-gun tube;
  • Fig. 3 is a cross-sectional view of the device shown in Fig. 2 in a plane at right angles to Fig. 2.
  • the cathode-ray tube shown in Fig. 1 comprises a wall I enclosing a luminescent screen 2 covered with a mosaic of superficial elements consisting of fluorescent materials of the kinds which become luminescent in the desired colors upon being excited by electrons.
  • a grid 3 comprising a large number of small apertures is provided in the vicinity of the screen 2.
  • Three substantially parallel electron guns each producing a directed electron beam, are provided in the neck of the tube for scanning the screen 2.
  • the beams produced by the guns are directed to a common point on an aperture in the grid 3 and in the case of parallel arrangement of the electron guns, the required convergence of the beams may be produced by the use of a focussing coil 4.
  • Each of the tubes 5, 6, and 1 contains an electrode gun, only that in tube 5 being shown diagrammatically, comprising a cathode 8, a control electrode 9 and an anode Ill.
  • a set of deflection coils l I for horizontal deflection of the beam and a set of deflection coils [2 for vertical deflection thereof are provided on the tube.
  • the collecting or luminescent screen 2 and the grid 3 use, alternatively, may be made of a grid constituted by parallel wires, the different luminescent substances being provided on the screen in lines having a width corresponding to the spacing between the grid wires.
  • the electron guns may be arranged in a straight line side by side at right angles to the direction of the grid wires. However, in the embodiment shown in Fig. 1, the guns are arranged in the form of a triangle.
  • the beams from the three guns are focussed by the magnetic device shown in detail in Figs. 2 and 3 comprising a system of pairs of magnetic poles which are energized by a common electrical winding I3 when the latter is traversed by electric current.
  • a common electrical winding I3 when the latter is traversed by electric current.
  • two circular parallel plates l4 and I5 are connected together by an annular upright edge I6 provided along their outer circumferences. Both the plates I4, 15 and the upright edge l6 are constituted by magnetic material.
  • a single energizing winding I3 is arranged between the plates [4, l5 near their outer edges.
  • Each plate l4, l5 contains three apertures I1 and I8, respectively, by means of which the device may be slipped over the tubes 5, 6, '1 comprising the electron guns.
  • Three hollow, adjustable pole members l9. each constituted by magnetic material, are in threaded engagement, respectively, with each of the apertures in the plate l5.
  • These pole members [9, each of which surround an electron gun, may be screwed in and out of the plate [5 to a greater or smaller extent so that the distance between the pole member l9 and the plate [4 varies and, hence, the strength of the magnetic field therebetween for focussing each individual beam.
  • a multi-gun cathode-ray tube for producing a plurality of directed electron beams which impinge at about the same point on a collecting screen, comprising an envelope supporting the collecting screen at one end thereof and including a cylindrical neck portion located at the opposite end, a plurality of electron guns, a plurality of distinct cylindrical tubes each housing one of said guns, said cylindrical tubes being substantially parallel to one another and being connected to said neck portion of said cathode-ray tube, and a magnetic device for directing said beams, said magnetic device comprising a plurality of pairs of magnetic poles each in proximity of one of said guns, and a single coil winding surrounding all of said pairs of poles for energization thereof.
  • a multi-gun cathode-ray tube as claimed in claim 1 in which said magnetic device comprises a pair of plane parallel magnetic plates for forming said pairs of magnetic poles and having apertures therein for engagement with said cylindrical tubes, said winding being positioned between said plates, and a magnetic member uniting said plates along their outer edges and enclosing said winding.
  • a multi-gun cathode-ray tube as claimed in claim 2 in which a plurality of adjustable sleeves of magnetic material are provided each of which is in engagement with one of said apertures in one of said plates and surrounds one of said guns for individually focussing each gun.

Landscapes

  • Video Image Reproduction Devices For Color Tv Systems (AREA)
  • Vessels, Lead-In Wires, Accessory Apparatuses For Cathode-Ray Tubes (AREA)
US320271A 1951-11-28 1952-11-13 Multigun cathode-ray tube Expired - Lifetime US2689922A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
NL165668 1951-11-28

Publications (1)

Publication Number Publication Date
US2689922A true US2689922A (en) 1954-09-21

Family

ID=19750546

Family Applications (1)

Application Number Title Priority Date Filing Date
US320271A Expired - Lifetime US2689922A (en) 1951-11-28 1952-11-13 Multigun cathode-ray tube

Country Status (7)

Country Link
US (1) US2689922A (en))
BE (1) BE515797A (en))
CH (1) CH309698A (en))
ES (1) ES206481A1 (en))
FR (1) FR1067170A (en))
GB (1) GB716769A (en))
NL (1) NL85814C (en))

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2847600A (en) * 1953-06-25 1958-08-12 Rca Corp Tri-color kinescope
US3035198A (en) * 1957-03-13 1962-05-15 Philips Corp Deflection and focusing apparatus for cathode ray tubes

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1051416B (de) * 1955-01-17 1959-02-26 Loewe Opta Ag Elektronenstrahlroehre, vorzugsweise Fernsehbildroehre

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2165028A (en) * 1933-12-29 1939-07-04 Emi Ltd Television and the like system employing cathode ray tubes
US2170944A (en) * 1937-05-29 1939-08-29 Bell Telephone Labor Inc Multicathode ray discharge device
US2407667A (en) * 1941-09-30 1946-09-17 Bell Telephone Labor Inc Harmonic generator
US2631259A (en) * 1950-07-12 1953-03-10 Rca Corp Color television

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2165028A (en) * 1933-12-29 1939-07-04 Emi Ltd Television and the like system employing cathode ray tubes
US2170944A (en) * 1937-05-29 1939-08-29 Bell Telephone Labor Inc Multicathode ray discharge device
US2407667A (en) * 1941-09-30 1946-09-17 Bell Telephone Labor Inc Harmonic generator
US2631259A (en) * 1950-07-12 1953-03-10 Rca Corp Color television

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2847600A (en) * 1953-06-25 1958-08-12 Rca Corp Tri-color kinescope
US3035198A (en) * 1957-03-13 1962-05-15 Philips Corp Deflection and focusing apparatus for cathode ray tubes

Also Published As

Publication number Publication date
FR1067170A (fr) 1954-06-14
GB716769A (en) 1954-10-13
ES206481A1 (es) 1953-01-01
NL85814C (en))
CH309698A (de) 1955-09-15
BE515797A (en))

Similar Documents

Publication Publication Date Title
US3448316A (en) Cathode ray tube
US3928785A (en) Single gun, multi-screen, multi-beam, multi-color cathode ray tube
US2672574A (en) Magnetic beam controlling system
USRE26035E (en) Post deflection focused single qun color tube
US2752520A (en) Tri-color kinescope
US2677779A (en) Tricolor kinescope magnetic shield
US2769110A (en) Electron beam control means
US2690517A (en) Plural beam electron gun
US3002120A (en) Beam convergence apparatus for tri-color kinescope
US2923844A (en) Cathode ray tube structure including convergence system
US3164737A (en) Cathode ray tube
US2689922A (en) Multigun cathode-ray tube
US2729759A (en) Beam controlling apparatus
US4455542A (en) Device for displaying television pictures including a deflection unit therefor
US2267823A (en) Scanning device for television
US3914641A (en) Electron gun construction for multi-beam color cathode ray tube
US2834901A (en) Cathode ray tube adjunct
US2643352A (en) Color kinescope
US2975325A (en) Electron beam deflection system
US2701847A (en) Color television tube structure
US2898493A (en) Method and apparatus for controlling electron beams
US2824267A (en) Deflection yoke for multi-beam cathode ray tube
US3188508A (en) Beam penetration color cathode ray tube
US3188507A (en) Beam penetration color cathode ray tube
US3316432A (en) Cathode ray tube electron gun mount with unitary magnetic centering and gettering means