US3032673A - Direct-view half-tone storage tube - Google Patents

Direct-view half-tone storage tube Download PDF

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Publication number
US3032673A
US3032673A US706842A US70684258A US3032673A US 3032673 A US3032673 A US 3032673A US 706842 A US706842 A US 706842A US 70684258 A US70684258 A US 70684258A US 3032673 A US3032673 A US 3032673A
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United States
Prior art keywords
screen
storage
electron
direct
storage 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.)
Expired - Lifetime
Application number
US706842A
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English (en)
Inventor
Kenneth R Hesse
Leon S Yaggy
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.)
Raytheon Co
Original Assignee
Hughes Aircraft 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
Priority to NL111827D priority Critical patent/NL111827C/xx
Priority to NL234621D priority patent/NL234621A/xx
Application filed by Hughes Aircraft Co filed Critical Hughes Aircraft Co
Priority to US706842A priority patent/US3032673A/en
Priority to GB40048/58A priority patent/GB848535A/en
Priority to CH362117D priority patent/CH362117A/de
Priority to BE573960A priority patent/BE573960A/fr
Priority to FR782295A priority patent/FR1217984A/fr
Priority to DEH35256A priority patent/DE1139212B/de
Application granted granted Critical
Publication of US3032673A publication Critical patent/US3032673A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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    • 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
    • H01J29/52—Arrangements for controlling intensity of ray or beam, e.g. for modulation
    • 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
    • H01J29/485—Construction of the gun or of parts thereof
    • 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
    • H01J31/12—Image or pattern display tubes, i.e. having electrical input and optical output; Flying-spot tubes for scanning purposes with luminescent screen
    • H01J31/18—Image or pattern display tubes, i.e. having electrical input and optical output; Flying-spot tubes for scanning purposes with luminescent screen with image written by a ray or beam on a grid-like charge-accumulating screen, and with a ray or beam passing through and influenced by this screen before striking the luminescent screen, e.g. direct-view storage tube

Definitions

  • This invention relates to direct-viewing half-tone storage tubes and more particularly to a half-tone directviewing storage tube incorporating an electron gun having a substantially greater video drive requirement.
  • a conventional direct-viewing half-tone storage tube comprises, for example, a viewing screen, means for directing ilood electrons uniformly over the viewing screen, a storage screen disposed adjacent to and coextensive with the viewing screen in the path of the ood electrons, and means including an electron writing gun for producing a charge replica on the storage screen thereby to control the ow of ilood electrons to the viewing screen to produce a visual image of the charge replica.
  • the electron writing gun employed in such half-tone storage tubes delivered many microamperes of beam current when the control grid was driven but a few volts from cutoff.
  • an electron writing gun which includes means for interceptng a substantial portion of the current of the writing beam subsequent to its being modulated by the application of a normal video signal on its control grid. More particularly, an electrode with an array of small apertures is inserted in the path of the electron beam subsequent to its intensity being determined by the amplitude of the video signal whereby only a predetermined percent of the electrons in the beam are permitted to pass through and arrive at the storage screen. The percent of the beam passing through the electrode is determined by the effective transparency thereof which in general will be determined by the ratio of the area of the apertures to the total area of the electrode.
  • the size of the apertures is small compared to the cross-sectional area of the writing beam and the number of apertures within the cross-sectional area is large enough so that there are no abrupt changes in the resulting beam current due to separate contributions of individual apertures when the beam current is varied with concomitant variations in cross-sectional area. It is thus apparent that the direct-viewing half-tone storage tube of the present invention can be operated withoutttaking special care or without employelectron writing gun adapted to operate with a substantially increased video signal drive.
  • Still another object of the present invention is to provide an electron writing gun for use in a storage tube, the electron gun having means to intercept a predetermined portion of the current constituting the electron writing beam subsequent to the varying of the intensity of the beam with a drive signal.
  • FIG. 1 illustrates a cross-sectional schematic view of Y the direct-viewing half-tone storage tube of the present invention
  • FIG. 2 shows a cross-sectional perspective view of the electron Writing gun in the device of FIG. 1;
  • FIGS. 3-5 illustrate plan views of alternate forms of an electrode in the electron gun of FIG. 2.
  • FIG. l of the drawings there is shown a cross-sectional schematic view of thedirect-viewing storage tube of the present invention which comprises an evacuated envelope 10.
  • This evacuated envelope 10 is constituted of an enlarged cylindrical portion 11 with a at faced portion 12 at one extremity thereof, and an enclosing portion 13 at the opposite extremity of the cylindrical portion 11.
  • the enclosing portion 13 of the evacuated envelope 10 includes an indented or well portion 14 in the center thereof opposite the at faced portion 12 and an arm portion 15 having a longitudinal axis which intersects with the longitudinal axis of the cylindrical portion 11 at an oblique angle, as shown in the drawing.
  • the indented or well portion 14 of the evacuated envelope 10 accommodates a ood gun 16 which includes a flood cathode 18.
  • the flood cathode 18 of flood gun 16 is maintained at a substantially fixed reference potential such as, for example, ground by means of an appropriate connection thereto.
  • the ood gun 16 in conjunction with electrodes 20, 22 directs a ow of flood electrons uniformly towards the at faced portion 12 of the kevacuated envelope 10. Electrodes 20, 22 are disposed successively about the inner periphery of cylindrical portion 11 of evacuated envelope 10 in proceeding, respectively, from the flood gun 16 to the flat faced portion 12.
  • electrode 20 extends over the enclosing portion 13 and into the arm portion 15 to provide an equipotential region in the left portion of evacuated envelope 10, as viewed in the drawing.
  • electrodes 20, 22 are maintained at potentials of the order of +l0 volts and +40 volts with respect to ground, respectively.
  • a viewing screen 24 which includes a fluorescent screen 25 covered with a thin metallic coating 26 of, for example, aluminum. Proceeding towards the ood gun 16 there is disposed adjacent to and coextensive with the viewing screen 24, in the order named, a storage screen 28 and a collector grid 30.
  • the storage screen 28 is o-f the type which may comprise, for example, an electro-formed metallic screen 31 on which there is evaporated a thin film 32 of, for example, magnesium fluoride on the side thereof facing ilood gun 16 to provide a storage surface.
  • the metallic coating 26 of viewing screen 24, the metallic screen 31 of storage screen 28 and the collector grid 30 are maintained at potentials of the order of +5000 volts, +5 volts and +120 volts with respect to ground, respectively. Further, the metallic screen 31 is connected to its respective source of potential through a resistor 33 and positive pulses generated thereacross by means of appropriate connections to a pulse generator 34. Under normal operation, these pulses will have positive excursions of from to 10 volts.
  • the arm portion l5 of evacuated envelope l0 accommodates an electron gun 35 for producing an electron writing beam in accordance with the present invention, and a deflection apparatus 36 for directing the electron writing beam towards selected elemental areas of storage screen 28.
  • the electron gun 35 includes a cathode 37 and an intensity control grid 38 which are maintained, respectively, at quiescent potentials of the order of 3000 volts and -3025 volts with respect to ground, respectively. This may be accomplished, for example, by connecting the control grid 38 through a resistor 39 to the negative terminal of a variable potential source itil, the positive terminal of which is connected to both cathode 37 and the negative terminal of a 3000 volt battery 4l, the positive terminal of which is referenced to ground. Signals provided by a signal source 39 are applied to control grid 3S of electron gun 35 through a capacitor 42.
  • the cathode 37 may, for example, be provided by a sleeve-type cathode which is heated by means of ya heater filament 44.
  • the control grid 38 comprises a metallic disc with a circular aperture disposed concentrically about a center line through the emitter surface of cathode 37.
  • an anode 46 and a lens assembly 4S.
  • the anode 46 constitutes an elongated cylindrical portion 49 which has an apertured appendage 50 on the extremity thereof adjacent the control grid 38.
  • the lens assembly 48 comprises narrow cylindrical members 52, 53 disposed concentrically about the path of the electron beam which members 52, 53 have a diameter of the order of two times the diameter of cylindrical portion 49 of anode 46.
  • circular discs 54, 55 are appended to the opposite extremities of cylindrical members 52, 53, respectively, with circular apertures therethrough to accommodate the ow of the electron beam.
  • Circular disc 54 is, in turn, attached to the adjacent extremity of the cylindrical portion 49 of the anode 46.
  • Lens assembly 48 also includes a cylindrical member 56 interposed between and of the same diameter as the cylindrical members 52, 53. In operation, the anode 46 and cylindrical member 52, the cylindrical member 56, and the cylindrical member 53 are maintained at potentials of the order of l0 volts, 2400 volts and l() volts, with respect to ground, respectively.
  • an electrode S8 having an array of holes or apertures is disposed over the aperture in disc 54 in the path of the electron beam.
  • the electrode 58 may, for example, constitute an electroformed mesh 58a (see FIG. 3), a photo-etched sheet 58b (see FIG. 4), a woven screen 58C (see FIG. 5) or any construction which results in a sheet which is opaque to electrons except at small, evenly distributed areas.
  • the transparency of electrode 58 is of the order of 1%.
  • the electrode S8 can be located at any plane normal to the path of the beam where the beam is in a defocused condition and subsequent to its intensity being determined by the amplitude of a video drive signal, namely, along the path of the electron beam subsequent to its passing through the control grid 38. Due to the low relative transparency, it is highly desirable that the electrode 58 is not placed in a position such that it intercepts a portion of the flow of flood electrons. As mentioned above, a convenient location for the electrode 58 is at the aperture in disc 54 through which the beam passes before entering the focusing lield. It is, of course, apparent that either elecag. trostatic or magnetic focusing may be used. In addition to the above, the electrode S8 may also be located at a plane after the beam emerges from the focusing eld before deflection takes place, or even after some deflection has occurred.
  • the inherent capacitance between the metallic screen 31 and the storage surface of storage screen 28 initially raises the potential existing on the storage surface to
  • the ood electrons emanating from flood cathode i8 maintained at ground potential immediately commence discharging the storage surface to ground potential.
  • Subsequent pulsing of the metallic screen 31 of storage screen 28 periodically raises the potential of the storage surface 5 to 10 volts positive with respect to ground, depending on the amplitude of the pulse excursions. During these periodic pulse intervals when the storage surface is positive with respect to ground the flood electrons impnge on the storage surface to charge it towards ground potential.
  • the storage surface assumes a quiescent potential that is negative with respect to ground to the extent of the pulse amplitude. At this quiescent negative potential, substantially all the ood electrons are repelled and thus prevented from penetrating through the storage screen 28 to the viewing screen 24.
  • a charge replica is produced next on the storage surface by the application of the signal provided by the signal source 39 to the intensity control grid 38 of electron Writing gun 3S and scanning the electron beam over the storage surface in synchronism therewith by means of the deliection apparatus 36.
  • the variation in the potentials constituting the charge replica be restricted to from l to 3 volts.
  • this restriction made it necessary to bias the electron writing beam to substantially cut-olf whereupon only a comparatively low amplitude video drive signal was required to produce a charge replica having the desired variation in potentials.
  • the intensity of a substantial ow of electrons may first be controlled by intensity grid 38 of electron gun 35 after which a substantial portion of the electron beam is intercepted by the perforated or foraminous electrode 58.
  • a video drive signal of convenient amplitude may be employed consistent with producing a charge replica having the requisite potential variations of only 1 to 3 volts thereby to preserve the half-tones in the visual presentation.
  • the continued pulsing of the metallic screen 31 by the pulse generator 34 will enable the flood electrons to proceed to erase the charge replica thus produced.
  • a half-tone direct-viewing storage tube comprising a viewing screen; means for directing flood electrons uniformly towards said viewing screen; a storage screen disposed adiacent to and coextensive with said viewing screen in the path of said flood electrons; and means for producing a charge replica on said storage screen thereby to control the flow of said flood electrons to said viewing screen, said last-named means including a source of electrons, means for directing said electrons along a predetermined path thereby to produce an electron beam, said electron beam being defocused over at least a portion of the length of said predetermined path, means disposed adjacent said source of electrons and prior to said portion of said predetermined path for controlling the intensity of said electron beam in response to an electrical signal, and a substantially uniformly multi-apertured electrode inserted in said electron beam along said portion of said path wherein said electron beam is defocused and at a point therealong not exposed to ood electrons thereby to decrease the intensity of said elec- 5 6 tron beam, and means for directing the

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  • Cathode-Ray Tubes And Fluorescent Screens For Display (AREA)
  • Overhead Projectors And Projection Screens (AREA)
US706842A 1958-01-02 1958-01-02 Direct-view half-tone storage tube Expired - Lifetime US3032673A (en)

Priority Applications (8)

Application Number Priority Date Filing Date Title
NL111827D NL111827C (de) 1958-01-02
NL234621D NL234621A (de) 1958-01-02
US706842A US3032673A (en) 1958-01-02 1958-01-02 Direct-view half-tone storage tube
GB40048/58A GB848535A (en) 1958-01-02 1958-12-11 Direct-viewing half-tone storage tube
CH362117D CH362117A (de) 1958-01-02 1958-12-16 Halbtöne wiedergebende Direktsicht-Speicherbildröhre
BE573960A BE573960A (fr) 1958-01-02 1958-12-17 Tube récepteur demi-teinte à entretien d'image
FR782295A FR1217984A (fr) 1958-01-02 1958-12-22 Tube accumulateur à vision directe en demi-teintes
DEH35256A DE1139212B (de) 1958-01-02 1958-12-31 Direktsicht-Speicherroehre zur Erzeugung eines auch Zwischentoene enthaltenden Bildes

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US706842A US3032673A (en) 1958-01-02 1958-01-02 Direct-view half-tone storage tube

Publications (1)

Publication Number Publication Date
US3032673A true US3032673A (en) 1962-05-01

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ID=24839286

Family Applications (1)

Application Number Title Priority Date Filing Date
US706842A Expired - Lifetime US3032673A (en) 1958-01-02 1958-01-02 Direct-view half-tone storage tube

Country Status (7)

Country Link
US (1) US3032673A (de)
BE (1) BE573960A (de)
CH (1) CH362117A (de)
DE (1) DE1139212B (de)
FR (1) FR1217984A (de)
GB (1) GB848535A (de)
NL (2) NL234621A (de)

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB521803A (en) * 1937-11-24 1940-05-31 Fernseh Ag Improvements in or relating to cathode ray tubes
GB534215A (en) * 1939-07-28 1941-03-03 Otto Klemperer Improvements in or relating to electron discharge devices
US2318423A (en) * 1941-10-28 1943-05-04 Bell Telephone Labor Inc Electron discharge device
US2728872A (en) * 1953-10-23 1955-12-27 Hughes Aircraft Co Direct-viewing storage tube with character writing electron gun
US2761988A (en) * 1954-03-08 1956-09-04 Gen Dynamics Corp Cathode ray apparatus
US2790929A (en) * 1954-09-30 1957-04-30 Hughes Aircraft Co Direct-viewing half-tone storage device
US2826716A (en) * 1957-01-31 1958-03-11 Gen Dynamics Corp Beam selection system
US2880342A (en) * 1956-10-25 1959-03-31 Gen Dynamics Corp Electron beam for a cathode ray tube

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE740028C (de) * 1937-11-24 1943-10-11 Fernseh Gmbh Anordnung zur Erzeugung eines Bildpunktes in intensitaetsgesteuerten Hochvakuumkathodenstrahlroehren
GB673502A (en) * 1949-05-26 1952-06-04 Standard Telephones Cables Ltd Improvements relating to cathode-ray storage tube systems
BE510008A (de) * 1951-04-28 Cfcmug
BE513449A (de) * 1951-08-11
GB762137A (en) * 1954-04-28 1956-11-21 Hughes Aircraft Co Electronic storage tube
BE548406A (de) * 1955-07-12

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB521803A (en) * 1937-11-24 1940-05-31 Fernseh Ag Improvements in or relating to cathode ray tubes
GB534215A (en) * 1939-07-28 1941-03-03 Otto Klemperer Improvements in or relating to electron discharge devices
US2318423A (en) * 1941-10-28 1943-05-04 Bell Telephone Labor Inc Electron discharge device
US2728872A (en) * 1953-10-23 1955-12-27 Hughes Aircraft Co Direct-viewing storage tube with character writing electron gun
US2761988A (en) * 1954-03-08 1956-09-04 Gen Dynamics Corp Cathode ray apparatus
US2790929A (en) * 1954-09-30 1957-04-30 Hughes Aircraft Co Direct-viewing half-tone storage device
US2880342A (en) * 1956-10-25 1959-03-31 Gen Dynamics Corp Electron beam for a cathode ray tube
US2826716A (en) * 1957-01-31 1958-03-11 Gen Dynamics Corp Beam selection system

Also Published As

Publication number Publication date
NL111827C (de)
DE1139212B (de) 1962-11-08
CH362117A (de) 1962-05-31
GB848535A (en) 1960-09-21
FR1217984A (fr) 1960-05-06
NL234621A (de)
BE573960A (fr) 1959-04-16

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