US3723786A - Flat cathode-ray tube for direct viewing spot display - Google Patents

Flat cathode-ray tube for direct viewing spot display Download PDF

Info

Publication number
US3723786A
US3723786A US00121076A US3723786DA US3723786A US 3723786 A US3723786 A US 3723786A US 00121076 A US00121076 A US 00121076A US 3723786D A US3723786D A US 3723786DA US 3723786 A US3723786 A US 3723786A
Authority
US
United States
Prior art keywords
cathode
strip
electrode
electron
holes
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
US00121076A
Other languages
English (en)
Inventor
D Charles
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.)
Thales SA
Original Assignee
Thomson CSF SA
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 Thomson CSF SA filed Critical Thomson CSF SA
Application granted granted Critical
Publication of US3723786A publication Critical patent/US3723786A/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
    • H01J31/12—Image or pattern display tubes, i.e. having electrical input and optical output; Flying-spot tubes for scanning purposes with luminescent screen
    • H01J31/123—Flat display tubes
    • H01J31/125—Flat display tubes provided with control means permitting the electron beam to reach selected parts of the screen, e.g. digital selection
    • H01J31/126—Flat display tubes provided with control means permitting the electron beam to reach selected parts of the screen, e.g. digital selection using line sources

Definitions

  • the tube comprises an electron-gun embodying a series of cathodes 2 arranged on a conductive band A, Mar. l0, 1970 France ..7008540 an electrode C for the individual control of each of said cathodes in said series, and two additional parallel [52] US. Cl. ..3l3/70 R, 313/78 electrodes running along the band A over the whole of [51] Int. Cl ..H0lj 29/50, HOlj 31/12, HOlj 29/74 its length, one of then,F carrying a cathodolumin- [58] Field of Search "313/70, 69, 92 F secent coating and the other, E,metal strips 11.
  • the deflection imparted to the electron beam has a substantially analogue character, that is to say it varies continuously with the control signals applied to the deflection elements;
  • the length of the tube is in the order of the length of the diagonal of the effective part of the screen.
  • the present invention which relates to cathode ray tube for display applications, is intended to overcome these drawbacks.
  • FIG. 1 schematically illustrating a perspective view in connection with a cathode ray tube in accordance with the invention
  • FIGS. 2, 3, 4, 5, 6, 7 illustrating plan or elevational views of the elements of FIG. 1;
  • FIG. 8 providing an explanatory diagram of the operation of the tube of FIG. 1, utilizing a section taken in a plane perpendicular to the major dimension thereof; and, 7
  • FIGS. 9 and 10 illustrating an embodiment of the cathode ray tube schematically illustrated in FIG. 1.
  • FIG. 1 is a perspective viewshowing schematically the relative dispositions of the constitutive electrodes of a tube in accordance with the invention.
  • FIG. 1 which is given solely by way of example, there are shown six electrodes referenced A B C D E and F, each of which will be described more in detail hereinbelow. It goes without saying, that, without departing from the scope of the preset invention, it could be subtracted from or added to the device of FIG. 1, one or more electrodes provided that such subtraction or addition produce no fundamental modification in the principles of operation of the tube in accordance with the invention, as staded hereunder.
  • FIGS. 2, 3, 4 and 5 are plan views of the electrodes A, B, C and D of FIG. 1, as seen by an observer located above them, whilst FIGS. 6 and 7 provide elevational views of the electrodes E and F as seen by an observer located between them.
  • the electrode A (FIG. 2) is constituted by a flat conductor strip 1, for example of tungsten, upon which there are deposited at intervals, small identical equidistant square spots 2, of an electron-emissive material such as the type known generally as a cathode oxide.
  • the electrode B (FIG. 3) is constituted by a flat conductor strip 3, for example of non-magnetic nickel alloy, exhibiting a series of openings 4 in the form of squares substantially equal in size to the aforesaid spots, spaced apart from one another at the same spacing as the aforesaid spots 2.
  • the electrode C (FIG. 4) is constituted by a flat insulating strip 5, for example of ceramic, containing square openings whose number is equal to the number of the spots 2 and at the same spacing thereas, bordered by conductive eyelets 6 delimiting orifices substantially equal in size to the openings 4 and to the spots 2; the connections to the eyelets 6 are marked 7.
  • the electrode D (FIG. 5) is identical with the electrode B: a flat conductor strip 8 containing openings 9.
  • the electrodes A, B, C, and D are located parallel with one another andtheir position is adjusted so that the openings in the electrodes B, C, D are aligned'with the spots 2 of the electrode A, in the direction perpendicular to said electrode A.
  • FIG. 6 is an insulating plate 10, for example of glass, perpendicularly disposed in the example of FIG. 1, with regard to the electrodes A B C and D, bearing, on one of its faces, conductive coatings 11 in the form of mutually parallel equidistant strips, the long side of which is parallel to the plane of the strip A; these conductive strips are connected with the external circuit by connections 12. That face of the plate E which carries these coatings, is disposed towards the electrodeF.
  • the electrode F (FIG. 7) is constituted by a flat transparent plate 13, of glass for example, parallel to the plate E and entirely covered on that of its faces which is disposed towards the electrode E, firstly with a transparent conductive coating 15, for example tin oxide, this being connected with the external circuitry by the connection 14, and secondly by a coating of cathodoluminescent material marked '16.
  • a transparent conductive coating 15 for example tin oxide
  • spots 2 on the electrode A and of corresponding openings in the electrodes B, C, D is limited, for sake of clarity, to a few in the figures, but will be practically largely more numerous: there will be provided, spots 2 and 250 strips 11, for instance.
  • the electrode B is permanently at a potential which is some few volts positive with respect to the reference potential i.e., the potential of the electrode A.
  • the conductive eyelets 6 of the electrode C are placed in some cases at a voltage V of 30 to 50 volts and in other cases at a voltage which is a few volts negative, in accordance with a program which will depend upon the application of the tube.
  • the electrode D is permanently at a positive voltage of V,, of some few hundreds of volts, for example.
  • an electron beam will be emitted by thespot '2 of the electrode A which is located vis-a-vis with the eyelet 6 in question. This beam will pass through the space defined between the electrodes E and F via the hole 9 located vis-a-vis with the eyelet 6.
  • the conductive coating 15 of the electrode F is permanently maintained through the connection 14, at a voltage substantially equal to V
  • the conductive strips 11 deposited upon the plate E are in some cases placed at the voltage V and in some cases at a voltage which is less, by a quantity V than the voltage V namely V V in accordance with a program in connection with the program relating to the eyelets 6.
  • the electron beam coming from a spot 2 will be deflected towards the electrode F when it arrives at the level of a strip 11 raised to the potential V V hereinbefore referred to, as a consequence of the positive difference between the voltage V of the electrode F and the voltage of the strip in question. lts impact upon the layer 16 which covers the electrode, will gives rise to the luminescence of a point in said layer.
  • FIG. 8 This has been illustrated in FIG. 8, the latter being an explanatory diagram of the operation of the tube of FIG. 1, in which, for reasons of clarity, the conductive strips 11 have been enlarged and their number limited to 4.
  • 17 represents the trajectory of the electron beam coming from a spot (not shown) and passing in front of the three lower strips 11 which are at the voltage V,,, the arrow findicating the direction in which the beam is deflected on arriving in the neighborhood of the fourth strip which is at the voltage V V
  • the display of a light spot on the luminous layer 16 is obtained by switching the voltages V and V V respectively of the eyelet 6 and the strip 11, which define said point in accordance with the diagram of FIG. 8.
  • the voltages V and V are respectively referred to as the line control voltage and the column control voltage.
  • the conductive eyelets 6 of the electrode C and the conductive strips 11 of the plate E are connected to a switch which enables the voltages applied to be varied from V to some few volts negative for the eyelets 6, and from V to V V for the strips 11, depending upon what point on the luminescent layer is to be excited.
  • the voltage V is currently some few tens of volts.
  • the spots 2 in FIG. 2, in accordance with the invention (as many cathodes as there are lines), the same luminosity on impact of the electron beam upon the cathode-luminescent layer 16 (FIG. 7) can be obtained, other things being equal, at a much lower beam acceleration voltage than in conventional cathode-ray tubes.
  • This accelerating voltage is the column control voltage V as this results from the foregoing; in the case of the tubes in accordance with the invention, this voltage can be limited to some few tens of volts, a value compatible with the use of compact solid state switches which are increasingly being used in display techniques.
  • Another advantage of the invention rests in that the size of the cathode-ray tube of the invention, is substantially reduced with respect to that of known cathoderay tubes because of the bent trajectory of the electron beam between the cathodes 2 and the cathodoluminescent layer.
  • This size is virtually limited only by the breakdown voltage between the plates E and F, and it appears from what has been said hereinbefore that this voltage will not exceed more than some few tens of volts; it goes without saying that in this case the cathode strip A (FIG. 1) and consequently the spots 2, must be reduced in the same proportions, and E located close to F.
  • the spots of the electrode A, and consequently the openings in the electrodes B, C, D have been assumed to be regularly spaced.
  • the spacings between two successive spots may be arranged to vary throughout the electrode A.
  • the same remark applies to the conductive strips of the plate E.
  • An electrode B at a slightly positive potential in relation to the cathode A, is present, in the embodiment of FIG. 1.
  • Such an electrode being not necessary for a satisfactory operation of the tube in accordance with the invention, the latter applies also to a structure which does not comprise such an electrode.
  • a structure comprising several other electrodes in addition to the electrodes A, C and D provided for electronoptical reasons for example, as already remarked hereinbefore, is also within the scope of the present invention.
  • a collector or catcher no mention of which has been made until this point since it forms part of the prior art of electronic tubes, is essential in order to pick up the electrons of the beam which, in the absence of the voltage V will be propagated, without deflection, from the cathode A to the opposite end of the tube.
  • This catcher may furthermore, be formed quite simply by an additional conductive strip placed at a slightly higher potential than V and located on the plate E beyond the strips 1 1.
  • FIGS. 9 and 10 provide an exploded view of an example of a cathode-ray tube in accordance with the invention, in which the plates E and F form part of the tube envelope.
  • the envelope is constituted by two U-shaped components, both of glass for example; the plates E and F are constituted by the legs of one of the U-shaped components, respectively carrying the strips 11, on the one hand, and the layers 15 and 16 on the other hand,
  • the base of the other U-shaped component carries the electrodes A, C and D.
  • the two U-shaped components, separately manufactured, are attached together around the whole of their peripheries a and b, by a vacuum-tight bond, using one of the prior art techniques.
  • FIG. 9 70 are leadin-wires each of which is in electrical contact with one of the connections 7.
  • a cathode-ray tube which comprises, inside an evacuated envelope, at least a portion of which is transparent, an electron-gun and an electron collector, said gun comprising a cathode in form of a first elongated surface, and at least one control electrode and comprising two additional flat plates extending in the direction of said cathode and perpendicularly to its surface, one of which called the first electrode plate, visible through said transparent portion, is transparent and is covered, on that face disposed towards the other of said two additional plates with a thin, transparent, conductive film itself coated with a cathodoluminescent material, and the other of which, called the second plate, carries parallel conductive strips insulated from one another and extending across the large side of said surface, in the form of rectangles whose large sides are parallel to the large side of said surface, wherein said cathode is a flat rectangular metal strip covered at intervals with small areas of an electron-emissive material and said control electrode is a flat rectangular strip of insulating material parallel to said ca
  • a cathode-ray tube as described in claim 1 further comprising: An additional flat rectangular metal electrode also parallel to said strip on the side thereof corresponding to electron flow and pierced by spaced holes alligned with the holes emissive areas and eyelets.

Landscapes

  • Cathode-Ray Tubes And Fluorescent Screens For Display (AREA)
US00121076A 1970-03-10 1971-03-04 Flat cathode-ray tube for direct viewing spot display Expired - Lifetime US3723786A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
FR7008540A FR2082304A5 (fr) 1970-03-10 1970-03-10

Publications (1)

Publication Number Publication Date
US3723786A true US3723786A (en) 1973-03-27

Family

ID=9052027

Family Applications (1)

Application Number Title Priority Date Filing Date
US00121076A Expired - Lifetime US3723786A (en) 1970-03-10 1971-03-04 Flat cathode-ray tube for direct viewing spot display

Country Status (4)

Country Link
US (1) US3723786A (fr)
DE (1) DE2111438A1 (fr)
FR (1) FR2082304A5 (fr)
GB (1) GB1290993A (fr)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4158157A (en) * 1976-10-26 1979-06-12 Zenith Radio Corporation Electron beam cathodoluminescent panel display
US4335380A (en) * 1980-06-16 1982-06-15 Wright David Y Multi-beam raster scan display monitor
FR2647580A1 (fr) * 1989-05-24 1990-11-30 Clerc Jean Dispositif d'affichage electroluminescent utilisant des electrons guides et son procede de commande
US4980613A (en) * 1988-02-08 1990-12-25 Matsushita Electric Industrial Co., Ltd. Flat CRT display apparatus
US5117159A (en) * 1988-11-04 1992-05-26 Matsushita Electric Industrial Co., Ltd. Flat panel type display and method for driving the display

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4487673A (en) * 1982-04-21 1984-12-11 Rca Corporation Method of making a line cathode having localized emissive coating

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2506627A (en) * 1945-09-14 1950-05-09 Emi Ltd Electron discharge device
US2858464A (en) * 1955-09-26 1958-10-28 Westinghouse Electric Corp Cathode ray tube
US2879446A (en) * 1956-02-08 1959-03-24 Kaiser Ind Corp Electronic device
US2978608A (en) * 1956-12-24 1961-04-04 Ibm Character synthesizing tube
US3198976A (en) * 1960-04-28 1965-08-03 Rank Precision Ind Ltd Electric discharge tubes and applications thereof
US3558967A (en) * 1969-06-16 1971-01-26 Varian Associates Linear beam tube with plural cathode beamlets providing a convergent electron stream

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2506627A (en) * 1945-09-14 1950-05-09 Emi Ltd Electron discharge device
US2858464A (en) * 1955-09-26 1958-10-28 Westinghouse Electric Corp Cathode ray tube
US2879446A (en) * 1956-02-08 1959-03-24 Kaiser Ind Corp Electronic device
US2978608A (en) * 1956-12-24 1961-04-04 Ibm Character synthesizing tube
US3198976A (en) * 1960-04-28 1965-08-03 Rank Precision Ind Ltd Electric discharge tubes and applications thereof
US3558967A (en) * 1969-06-16 1971-01-26 Varian Associates Linear beam tube with plural cathode beamlets providing a convergent electron stream

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4158157A (en) * 1976-10-26 1979-06-12 Zenith Radio Corporation Electron beam cathodoluminescent panel display
US4335380A (en) * 1980-06-16 1982-06-15 Wright David Y Multi-beam raster scan display monitor
US4980613A (en) * 1988-02-08 1990-12-25 Matsushita Electric Industrial Co., Ltd. Flat CRT display apparatus
US5117159A (en) * 1988-11-04 1992-05-26 Matsushita Electric Industrial Co., Ltd. Flat panel type display and method for driving the display
FR2647580A1 (fr) * 1989-05-24 1990-11-30 Clerc Jean Dispositif d'affichage electroluminescent utilisant des electrons guides et son procede de commande

Also Published As

Publication number Publication date
DE2111438A1 (de) 1971-09-23
GB1290993A (fr) 1972-09-27
FR2082304A5 (fr) 1971-12-10

Similar Documents

Publication Publication Date Title
US3500102A (en) Thin electron tube with electron emitters at intersections of crossed conductors
US4341980A (en) Flat display device
US5083058A (en) Flat panel display device
US5170100A (en) Electronic fluorescent display system
EP0201609B1 (fr) Canon a electrons d'un dispositif d'affichage d'images
US3622828A (en) Flat display tube with addressable cathode
US3214631A (en) Tube having target with store and/or non-store sections
US3293473A (en) Thin, porous storage phosphor layer
US3723786A (en) Flat cathode-ray tube for direct viewing spot display
US4387322A (en) Display arrangements
US3890541A (en) Cathode ray tube apparatus
US2695372A (en) Grid structure for cathode-ray tubes
US3102212A (en) Cathode ray tube with low velocity deflection and post deflection beam acceleration
US3339099A (en) Combined direct viewing storage target and fluorescent screen display structure
US6008577A (en) Flat panel display with magnetic focusing layer
US3780326A (en) Symbol display tube with auxiliary electrode
US4045703A (en) Flat envelope type fluorescent character indicating tube with getter shield plate
US3313975A (en) Electron impervious flexible shield member for electron discharge tubes
US4316118A (en) Guided beam display device
US4143296A (en) Flat panel display device
JPS5913138B2 (ja) 表示装置
US4193014A (en) Display arrangements
US3401293A (en) Mesa type combined direct viewing storage target and fluorescent screen for cathode ray tube
GB2031219A (en) Crt matrix display
US3519874A (en) Divided screen display tube for store/non-store information presentation