US3375391A - Thin image tube assembly - Google Patents

Thin image tube assembly Download PDF

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Publication number
US3375391A
US3375391A US474066A US47406665A US3375391A US 3375391 A US3375391 A US 3375391A US 474066 A US474066 A US 474066A US 47406665 A US47406665 A US 47406665A US 3375391 A US3375391 A US 3375391A
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United States
Prior art keywords
faceplate
tube
cavity
spacing
screen
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
US474066A
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English (en)
Inventor
Cyril L Day
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.)
TDK Micronas GmbH
ITT Inc
Original Assignee
Deutsche ITT Industries GmbH
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 Deutsche ITT Industries GmbH filed Critical Deutsche ITT Industries GmbH
Priority to US474066A priority Critical patent/US3375391A/en
Priority to FR70534A priority patent/FR1487614A/fr
Application granted granted Critical
Publication of US3375391A publication Critical patent/US3375391A/en
Anticipated expiration legal-status Critical
Assigned to ITT CORPORATION reassignment ITT CORPORATION CHANGE OF NAME (SEE DOCUMENT FOR DETAILS). Assignors: INTERNATIONAL TELEPHONE AND TELEGRAPH CORPORATION
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
    • H01J29/02—Electrodes; Screens; Mounting, supporting, spacing or insulating thereof
    • H01J29/10—Screens on or from which an image or pattern is formed, picked up, converted or stored
    • H01J29/36—Photoelectric screens; Charge-storage screens
    • H01J29/39—Charge-storage screens
    • H01J29/395—Charge-storage screens charge-storage grids exhibiting triode effect
    • 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
    • H01J31/50—Image-conversion or image-amplification tubes, i.e. having optical, X-ray, or analogous input, and optical output
    • H01J31/505—Image-conversion or image-amplification tubes, i.e. having optical, X-ray, or analogous input, and optical output flat tubes, e.g. proximity focusing tubes
    • 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
    • H01J31/50—Image-conversion or image-amplification tubes, i.e. having optical, X-ray, or analogous input, and optical output
    • H01J31/506—Image-conversion or image-amplification tubes, i.e. having optical, X-ray, or analogous input, and optical output tubes using secondary emission effect
    • 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
    • H01J31/50—Image-conversion or image-amplification tubes, i.e. having optical, X-ray, or analogous input, and optical output
    • H01J31/52—Image-conversion or image-amplification tubes, i.e. having optical, X-ray, or analogous input, and optical output having grid-like image screen through which the electron ray or beam passes and by which the ray or beam is influenced before striking the luminescent output screen, i.e. having "triode action"

Definitions

  • a thin image tube assembly and mounting includes a display screen at one end of a cylindrical envelope and a faceplate having a photoconductive screen at the other end. Annular insulating spacers positioned along the inner surface of the tube abut and support two intermediate mesh screens. The spacer adjacent the photoconductive screen is flush with the edge of the envelope and a metal ring forms a seal between the faceplate, envelope and spacer to retain the elements in position. Close spacing between the two ends permits proximity focusing of an image onto the display screen.
  • This invention relates gene-rally to image tubes, and more particularly, to a storage image tube having an 1nternal structure which permits the provision of an extremely thin tube.
  • Storage image tubes are commonly used for receiving and storing a radiation image and thereafter optically displaying the stored image.
  • Such tubes conventionally comprise a photocathode, an insulator screen, a collector electrode, a phosphor display screen, and electrostatic lens or magnetic focusing elements.
  • the photocathode converts the incident radiation image into a corresponding electron beam, impingement of the electron beam upon the insulator screen providing by secondary emission a corresponding charge image which can be stored for a period of time.
  • uniform illumination of the photocathode provides a flood beam of electrons which pass through the apertures in the insulator screen to the phosphor display screen, being modulated by the charge image on the insulator screen, thereby providing an optical image corresponding to the charge image and in turn to the initial radiation image.
  • the insulator or storage screen and the collector electrode most commonly a fine mesh metal screen, and electrostatic lens elements have been supported by techniques commonly employed in the vacuum tube art, i.e., by various supports fused to the wall of the envelope. While such methods and techniques for supporting the internal elements have been satisfactory in the case of larger tubes having appreciable length, there are applications for storage image tubes where it is desirable that the tube be as thin as possible, it being, however, extremely difficult to provide a tube construction of the desired thinness with such conventionalelectrode supporting techniques. In addition, proximity focusing may be employed in a thin tube, thus eliminating electrostatic or magnetic focusing. It is therefore desirable to provide a storage image tube construction in which the internal elements are properly spaced and supported without attachment to the envelope wall, thus permitting the provision of an extremely thin tube.
  • Another object of the invention is to provide an improved image tube in which the internal elements are supported and spaced without attachment to the walls of the envelope.
  • a further object of the invention is to provide an improved storage image tube which is thinner than tubes heretofore provided.
  • the internal electrodes are supported and spaced by a plurality of spacing members which respectively abut the electrodes and the face plates of the tube thereby clamping the electrodes and supporting the same in assembled relation in the tube without requiring that the electrodes be attached to the wall of the envelope for support.
  • FIG. 1 is an enlarged cross-sectional view showing an embodiment of the improved storage image tube of the invention.
  • FIG. 2 is a fragmentary cross-sectional view showing a modification of the embodiment of FIG. 1.
  • the improved thin storage image tube of the invention includes an evacuated envelope 11 comprising a cup-shaped member 12 formed of glass or ceramic and a faceplate 13 sealed to the cup-shaped member 12 by an indium seal ring 14 as will hereinafter be more fully described.
  • Faceplate 13 may be formed of suitable material such as glass, sapphire, fused silica or lithium fluoride.
  • the glass cup-shaped member 12 comprises a cylindrical side wall 15 integrally joined to a bottom wall or faceplate 16.
  • Bottom wall 16 is suitably ground and polished and defines cavity 17 with the side wall 15, the inside surface 18 of the cylindrical side wall having a constant diameter of a size to permit the spacing members and electrodes to slide down into cavity 17 Without unnecessary clearance, as will be hereinafter described.
  • the edge 19 of the side Wall 15 is optically ground and polished or fire polished, as will be hereinafter more fully described; and it will be seen that the faceplate 13, which is cylindrical and has its opposite surfaces ground and polished, closes the cavity 17.
  • a metal exhaust tubulation 20 is fused or brazed in the side wall 15 in conventional fashion and communicates with cavity 17.
  • a separate cylindrical spacing member or faceplate 22 is provided having flat opposite ground and polished surfaces 23, 24 and a chamfered peripheral edge 25 thereby permitting the faceplate 22 to lay flat or to abut the bottom wall 16 of the cup-shaped member 12.
  • a conventional phosphor display screen 26 is deposited on the inner surface 24 of the faceplate 22 preferably with a conventional aluminum coating 27, as is well known to those skilled in the art.
  • the facing surfaces 23, 28 of the faceplate 22 and the bottom wall 16 respectively having coinciding metallized rings 29, 3t) thereon mutually forming contacts,
  • the metallized ring 30 on the bottom wall 16 being cou-.
  • the metal tubulation 20 thus serving as an external lead for the phosphor 26.
  • the metallized contact rings 29, 30 are shown as having appreciable thickness; however, that in actual practice these rings are of film thickness so that the surface 23 of the faceplate 22 essentially abuts the surface 28 of the bottom wall 16.
  • the inner surface 34 of faceplate 13 is coated with a conventional transparent conductive coating 35, such as tin oxide, or some other means of making electrical contact, and a conventional photocathode 36 is deposited on the transparent conductive coating 35, or contact, as is well known to those skilled in the art.
  • the indium seal ring 14 has an annular radially inwardly extending flange portion 37 which engages the edge 19 of the side wall 15 of the cup-shaped member 12 and the transparent conductive coating or contact 35 on the faceplate 13, a cold vacuum-tight seal being formed by the application of pressure, as is well known to those skilled in the art.
  • Insulator screen 38 is provided extending across the cavity 17 and spaced in parallel relationship with the faceplates 13, 22.
  • Insulator screen 38 comprises a fine mesh metal screen 39 stretched over a heavy, annular metal support ring 40 and fastened thereto, in any suitable fashion, as by resistance welding.
  • a layer 42 of insulating material, such as silicon or magnesium oxide is deposited on the side of the metal screen 39 facing the photocathode 36 in any suitable manner, as by vacuum evaporation methods well known to those skilled in the art.
  • a collector screen 43 comprising a fine mesh metal screen 44 extending across cavity 17 in spaced parallel relationship to the insulator screen 38 and the faceplate 13.
  • the fine mesh metal screen 44 is stretched over a heavy, annular metal support ring 45 and is fastened thereto in any suitable fashion, as by resistance welding.
  • the outside diameters of the metal support rings 40, 45 are slightly less than the inside diameter 18 of the side wall 15 of the cup-shaped member 12 so as to permit them to be slid down into the cavity 17 with a slip fit.
  • Spacing members 46, 48 may be formed of glass or a suitable ceramic, while spacing member 47 may be formed either of mica or a suitable ceramic since an annular ring of glass of the requisite thinness would be hard to handle without breaking. Spacing member 46 abuts the aluminum coating 27 on the inner surface 24 of faceplate 22 radially outwardly from the phosphor display screen 26-.
  • the aluminum coating 27 is shown as having appreciable thickness; however, that in actual practice, aluminum coating 27 will be of film thickness and thus that the spacing member 46 essentially abuts the faceplate 22.
  • the metal mounting ring 40 in turn abuts the spacing member 46 and is abutted by the thin spacing member 47.
  • Spacing member 47 is abutted by the metal mounting ring 45 Which in turn is abutted by spacing member 48.
  • the outside diameters of the spacing members 46, 47, 48 are slightly smaller than the inside diameter 13 of the side wall 15 to permit them to be slid down inside the cavity 17 with a slip fit.
  • the edge 19 of the side wall 15 of cupshaped member 12 has previously been optically ground and polished until the inside height of the side wall 15 is equal to the combined height of the spacing members and screen, i.e., so that the edge 19 is flush with the outer surface 49 of insulating member 48.
  • the annular flange portion 37 of the indium seal ring 14 has a portion 50 extending radially inwardly from the side wall 15.
  • ribbon contacts 52, 53 are attached to the metal mounting rings 40, 45 in any suitable fashion, as by resistance welding, the ribbon contacts 52, 53 in turn being secured to conventional external leads 54, 55 extending through the side wall 15 of the cup-shaped member 12, as is well known to those skilled in the art.
  • the phosphor and aluminum coatings 26, 27 and the metallized ring 29 are preformed 0n the faceplate 22 in conventional fashion prior to assembly of the faceplate 22 in the cup-shaped member 12.
  • the metal exhaust tubulation 20, metallized ring 30 and lead 32, and the leads 54 and 55 are likewise secured to the cup-shaped member 12 before assembly.
  • the face-plate 22 with the phosphor and aluminum coatings 26, 27 and the metallized ring 29 thereon, the spacing members 46, 47, 48 and the insulator and collector screens 38, 43 are then stacked in the cavity 17 in the order shown, the ribbon contacts 52, 53 being connected to the metal support rings 40, 45 by resistance welding as the respective screens are placed on top of the respective spacing members.
  • This sub-assembly may then be placed in a container and sealed to a vacuum system. After this container is well exhausted, the temperature is slowly raised to an elevated level, such as on the order of 400 C. and held there until the pressure drops to at least 2 10-' torr while hot. The container is then cooled and sealed off under vacuum thus keeping the parts therein clean and exhausted for storing until needed for final assembly of the tube.
  • an elevated level such as on the order of 400 C. and held there until the pressure drops to at least 2 10-' torr while hot.
  • the container is then cooled and sealed off under vacuum thus keeping the parts therein clean and exhausted for storing until needed for final assembly of the tube.
  • the transparent conductive coating or contacts 35 on the faceplate 13 is likewise preformed and the faceplate 13 with the transparent conductive coating or contact 35 thereon may then be placed in a separate container which is then evacuated and the photocathode 36 is then deposited in conventional fashion as is well known to those skilled in the art.
  • the faceplate 13 with the photocathode 36 thereon, as above-described, and the cup-shaped member 12 with the remaining parts therein are removed from their respective processing containers, the indium seal ring 14 is positioned on the edge 19 of the side wall 15, and the faceplate 13 is sealed to the side wall'15 by the application of suitable pressure, as is well known to those skilled in the art.
  • the thus assembled tube is then attached to a vacuum pump (not shown) by means of the exhaust tubulation 20 and is pumped down to the desired vacuum following which the exhaust tubulation 20 is pinched off.
  • An ion pump is conventionally used to pump the ultimate vacuum on the tube.
  • indium seal ring 14 has been illustrated and described for sealing the faceplate 13 to the cup-shaped member 12, it will be readily understood that other conventional means of sealingly attaching the faceplate 13 to the cup-shaped member 12 may be employed and that in such instances, the top spacing member 48 may directly abut the inner surface 34 of the faceplate 13. It will be observed that large central apertures are formed in the metal mounting rings 40, 45 and the annular spacing members 46, 47, 48 thus exposing the insulator screen 38 and the collector screen 44 to the display screen 26 and the photocathode 36. While the use of evacuated processing containers has been described, this method of assembly does not form a part of my invention and in the case of some cathodes, other conventional assembly techniques may be employed.
  • FIG. 2 of the drawing a modification of the invention is shown, in which a glass exhaust tubulation 56 is provided instead of the metal tubulation 20 of the previous embodiment and in which the phosphor display screen 26 and aluminum coating 27 are deposited directly on the inner surface 28 of the bottom wall 16 of the cup-shaped member 12 rather than on the separate spacing or faceplate member 22, as shown in FIG. 1.
  • a glass tubulation 56 since a glass tubulation 56 is employed, a separate external lead 57 is brought out through the bottom wall 16 from the aluminum coating 28 to provide the phosphor contact.
  • the bottom spacing member 46 abuts the aluminum coating 27, it again being recognized that for purposes of illustration in the drawing, the aluminum coating 27 is shown as having appreciable thickness whereas in actual practice it will be of film thickness so that the facing member 46 would in essence abut the inner surface 28 of the bottom wall 16.
  • the invention permits the provision of an extremely thin storage image tube since the necessity for attaching the internal metal electrodes to supporting elements attached to the wall of the envelope is completely eliminated, the tube being assembled by merely placing the spacing members and screens in the envelope in the proper sequence.
  • a storage im-age tube comprising: a cup-shaped member having a cylindrical side wall and a flat bottom wall mutually defining a cavity, said cup-shaped member being formed of insulating material and at least said bottom wall being transparent; a first flat circular faceplate member formed of transparent insulating material extending across the open end of said cup-shaped member parallel with said bottom wall and closing said cavity; a metal ring extending over an outer surface of said first faceplate member and sealingly connecting said first faceplate member to the edge of said side wall and having a portion extending into said cavity; a second fiat circular faceplate member formed of transparent insulating material abutting said bottom Wall and extending across said cavity; a phosphor display screen supported on the surface of said second faceplate member facing said cavity; the abutting surface of said second faceplate member and bottom wall respectively having metallized rings formed thereon mutually forming contacts; first external lead means connected to said ring on said bottom wall and second internal lead means connecting the ring on said second faceplate member and said display screen; a photo
  • a storage image tube comprising: a cup-shaped member having a cylindrical side wall and a fiat bottom wall mutually defining a cavity, said cup-shaped member being formed of insulating material and at least said bottom wall being transparent; a flat circular faceplate member formed of transparent insulating material extending across the open end of said cup-shaped member parallel with said bottom wall and closing said cavity; a metal ring extending over an outer surface of said faceplate member and sealingly connecting said faceplate member to the edge of said side wall and having a portion extending into said cavity, the metal of said sealing ring being formable by pressure applied to said faceplate and side wall; a phosphor display screen supported on said bottom wall facing said cavity; first external lead means connected to said display screen; a photocathode supported on the surface of said faceplate member facing said cavity; internal lead means connecting said sealing ring to said photocathode; first and second annular metal rings in said cavity respectively spaced from each other and from said bottom wall and faceplate member; first and second fine mesh metal screens respectively secured to said first

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  • Vessels, Lead-In Wires, Accessory Apparatuses For Cathode-Ray Tubes (AREA)
US474066A 1965-07-22 1965-07-22 Thin image tube assembly Expired - Lifetime US3375391A (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
US474066A US3375391A (en) 1965-07-22 1965-07-22 Thin image tube assembly
FR70534A FR1487614A (fr) 1965-07-22 1966-07-22 Tube image

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US474066A US3375391A (en) 1965-07-22 1965-07-22 Thin image tube assembly

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Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3801848A (en) * 1970-09-04 1974-04-02 Philips Corp Television camera tube with mounting assembly for grid adjacent photoconductor
US3941998A (en) * 1974-02-26 1976-03-02 The University Of Illinois Foundation Optoelectronic sampling head
FR2335035A1 (fr) * 1975-12-10 1977-07-08 Bosch Gmbh Robert Transformateur d'image
US4223244A (en) * 1977-10-18 1980-09-16 Futaba Denshi Kogyo K.K. Fluorescent display device with position selecting and column/row selecting grids
US4274028A (en) * 1978-10-05 1981-06-16 W. H. Brady Company Ultraviolet light generation
US4307130A (en) * 1977-07-27 1981-12-22 Nv Optische Industrie "De Oude Delft" Method of making the cathode of a diode image intensifier tube
US5272413A (en) * 1990-06-05 1993-12-21 Matsushita Electric Industrial Co., Ltd. Flat panel display device and a method of making the same
US9242019B2 (en) 2014-03-13 2016-01-26 Stellarray, Incorporated UV pipe

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2495697A (en) * 1946-06-08 1950-01-31 Chilowsky Constantin Method and apparatus for intensifying electronic images
US2605335A (en) * 1949-05-25 1952-07-29 Gen Precision Lab Inc Light amplifier
US2808528A (en) * 1952-11-01 1957-10-01 Sylvania Electric Prod Electron discharge device and mounting
US2888513A (en) * 1954-02-26 1959-05-26 Westinghouse Electric Corp Image reproduction system
US2899590A (en) * 1959-08-11 Ceramic vacuum tube
US3201630A (en) * 1955-03-30 1965-08-17 Itt Charge storage sheet with tapered apertures

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2899590A (en) * 1959-08-11 Ceramic vacuum tube
US2495697A (en) * 1946-06-08 1950-01-31 Chilowsky Constantin Method and apparatus for intensifying electronic images
US2605335A (en) * 1949-05-25 1952-07-29 Gen Precision Lab Inc Light amplifier
US2808528A (en) * 1952-11-01 1957-10-01 Sylvania Electric Prod Electron discharge device and mounting
US2888513A (en) * 1954-02-26 1959-05-26 Westinghouse Electric Corp Image reproduction system
US3201630A (en) * 1955-03-30 1965-08-17 Itt Charge storage sheet with tapered apertures

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3801848A (en) * 1970-09-04 1974-04-02 Philips Corp Television camera tube with mounting assembly for grid adjacent photoconductor
US3941998A (en) * 1974-02-26 1976-03-02 The University Of Illinois Foundation Optoelectronic sampling head
FR2335035A1 (fr) * 1975-12-10 1977-07-08 Bosch Gmbh Robert Transformateur d'image
US4293790A (en) * 1975-12-10 1981-10-06 Robert Bosch Gmbh Image converter having cylindrical housing and photocathode separated by spacing element from luminescent screen on frustrum
US4307130A (en) * 1977-07-27 1981-12-22 Nv Optische Industrie "De Oude Delft" Method of making the cathode of a diode image intensifier tube
US4223244A (en) * 1977-10-18 1980-09-16 Futaba Denshi Kogyo K.K. Fluorescent display device with position selecting and column/row selecting grids
US4274028A (en) * 1978-10-05 1981-06-16 W. H. Brady Company Ultraviolet light generation
US5272413A (en) * 1990-06-05 1993-12-21 Matsushita Electric Industrial Co., Ltd. Flat panel display device and a method of making the same
US9242019B2 (en) 2014-03-13 2016-01-26 Stellarray, Incorporated UV pipe

Also Published As

Publication number Publication date
FR1487614A (fr) 1967-07-07

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Owner name: ITT CORPORATION

Free format text: CHANGE OF NAME;ASSIGNOR:INTERNATIONAL TELEPHONE AND TELEGRAPH CORPORATION;REEL/FRAME:004389/0606

Effective date: 19831122