US2909687A - Cathode ray tubes - Google Patents

Cathode ray tubes Download PDF

Info

Publication number
US2909687A
US2909687A US764127A US76412758A US2909687A US 2909687 A US2909687 A US 2909687A US 764127 A US764127 A US 764127A US 76412758 A US76412758 A US 76412758A US 2909687 A US2909687 A US 2909687A
Authority
US
United States
Prior art keywords
mesh
target structure
plate
grid
cathode ray
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
US764127A
Other languages
English (en)
Inventor
Turk Walter Ernest
Hendry Eric Douglas
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.)
Teledyne UK Ltd
Original Assignee
English Electric Valve Co Ltd
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 English Electric Valve Co Ltd filed Critical English Electric Valve Co Ltd
Application granted granted Critical
Publication of US2909687A publication Critical patent/US2909687A/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
    • H01J29/02—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
    • H01J29/41—Charge-storage screens using secondary emission, e.g. for supericonoscope
    • H01J29/413—Charge-storage screens using secondary emission, e.g. for supericonoscope for writing and reading of charge pattern on opposite sides of the target, e.g. for superorthicon
    • 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
    • H01J29/026—Mounting or supporting arrangements for charge storage screens not deposited on the frontplate

Definitions

  • This invention relates to cathode ray tubes and more specifically to video signal generating tubes of the kind in which video signals are obtained by scanning with a cathode ray a target structure in which a high resistance electric charge storing plate is mounted in close juxtaposition to but spaced and insulated from a grid or mesh.
  • Well known examples of tubes of this kind are television camera tubes such as the well known image orthicon tube.
  • a trouble frequently encountered with image orthicon and other tubes of the kind referred to is that of microphony caused by relative movement between the storage plate and the adjacent mesh. Such relative movement produces variation of effective capacitance with corresponding variation in picture signal output level.
  • the movement is commonly of the resonant type and resonant vibrations are often excited by relatively small shocks or vibrations.
  • the elfect is similar to microphony in thermionic valves.
  • Microphony in cathode ray tubes of the kind referred to may occur in any of the tubes in practical use today, but it is obviously most apt to occur in tubes having larger diameter target structures than in others.
  • the storage plate which is normally a thin membrane-like member of glass, is spaced from the mesh by an annular spacer or washer at the edge and between the two, the three parts plate, spacer and mesh, being clamped together with the spacer the middle of the Sandwich.
  • the present invention seeks to provide improved tubes of the kind referred to which shall have good antimicrophonic qualities and which shall, moreover, attain this advantage by means which are simple and economical to manufacture.
  • the invention may be applied to target structures in which the mesh is spaced from the glass membrane or other storage plate by means of strip spacers extending across the target and it is also applicable to target structures in which the mesh and storage plate arespaced in other, known, ways, e.g. by an annular washer.
  • the high resistance charge storage plate and the mesh or grid of the target structure of a tube of the kind referred to are cemented together by non-shrinking cement at least at a plurality of places distributed around and just outside the useful picture area of said structure.
  • the cement In the limit they may be long enough to be continous all round the picture area so that the plate and grid, instead of being cemented together at a pluralityof separated places distributed round the periphery of the picture area, are cemented together continuously all round the said periphery. It is important, in carrying out the invention, that the cement shall be practically non-shrinking otherwise it may strain, deform, weaken or even damage the plate and/ or grid when it dries.
  • cementing at separate distributed places is resorted to the number of places is not critical but good results have been achieved with six such places. They do not need to be located with precision and, in fact, they should not be exactly equally spaced around the picture area since the anti-microphonic qualities are obtained as the result of the destruction of circular symmetry achieved by the cementing. In the preferred practice the cementing is effected at only approximately equally spaced distributed places.
  • the target structure has strip spacers which extend across it between the mesh or grid and the storage plate and are so located that their inner edges lie just outside the picture area and, in eifect, frame that area, and the said mesh, plate and the spacers are all stuck together by the cement.
  • strip spacers is not essential and, where they are not provided, the mesh and plate are cemented together at least at places distributed round and just outside the useful picture area. In such cases a template is used to assist in applying the cement.
  • a good form of cement to use is that known in the United Kingdom under the trade designation Aquadag 660B but, of course, other suitable practically nonshrinking cements may be employed.
  • Fig. 1 is a purely schematic representation of an image orthicon tube as a whole
  • Fig. 2 is a face view of a preferred form of target structure in accordance with this invention
  • Fig. 3 is a sectional elevation showing, to a considerably larger scale than is used in Fig. 2, the detailed construction used to anchor the edge of the target structure. This edge anchoring arrangement is not per se part of the present invention.
  • the tube therein represented is of Well known general kind and comprises within the bulbous end of an evacuated envelope E (shown broken away) a photo-cathode P on the end wall of the tube, an accelerator electrode A, a target structure T carried in the customary cylindro-conical frame TF, a field mesh electrode P which serves, when the tube is in use, to ensure a uniform electro-static field, and a decelerator electrode D.
  • the present invention is concerned with the construction of the target structure T which is purely schematically represented in Fig. 1.
  • the target structure comprises a fine wire mesh or grid 1, which is stretched across the aperture of a mesh support ring 2, the edge of the circle of mesh being held in a recess in the support ring 2 by means of a flat ring 3 which is welded to the face of the recess and holds the edge of the circle of mesh firmly in place.
  • the mesh is strained flat across the aperture of the support ring 2 by being tensioned over the corner 4 of that ring as clearly shown in Fig. 3.
  • Parallel to and spaced from the mesh 1 is a high resistance glass charge plate 7 which is fixed at its circular edge to a socalled target sealing cranked ring 8 to which the glass is sealed.
  • the mesh 1 and the target plate 7 are spaced apart by means of four strip-like spacers arranged as chords to the target structure (see Fig. 2) and each of double construction comprising two layers of low thermal expansion material one on top of the other.
  • the two layers composing each strip are shown at and 6 in Fig. 3 and are welded at their ends to one another, the lower layer 5 (or both layers 5 and 6) being welded to a fiat annular surface provided on the support ring 2 outwardly of the clamp ring 3.
  • the inner edges of the four spaces constitute a rectangular frame lying just outside the edges of the useful picture area which is a rectangle similar to but a little smaller than the rectangular frame thus constituted.
  • the mesh 1 and the charge plate 7 are cemented together at a plurality of places approximately equally distributed round, and just outside of, the useful picture area. As shown there are six such places, at which there are short strips of cement represented by the black areas and applied to Cr. This cements the mesh, the plate and the strip all together at these places.
  • the cement strips G are not shown in Fig. 3.
  • the mesh and glass which of course extend right across the central aperture of the target structure, are treated as though one could see through them both, and the references 1 and 7 are both applied to the central aperture of the target structure while the inner edge of the mesh support ring and the corner 4 of that ring are both shown as circles.
  • the backing ring 9 is also formed with a pair of hooks 11 (not shown in Fig. 3) which serve the usual purpose of facilitating support of the target structure in position in the tube.

Landscapes

  • Vessels, Lead-In Wires, Accessory Apparatuses For Cathode-Ray Tubes (AREA)
  • Cathode-Ray Tubes And Fluorescent Screens For Display (AREA)
US764127A 1957-11-28 1958-09-29 Cathode ray tubes Expired - Lifetime US2909687A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB37117/57A GB851757A (en) 1957-11-28 1957-11-28 Improvements in or relating to cathode ray tubes

Publications (1)

Publication Number Publication Date
US2909687A true US2909687A (en) 1959-10-20

Family

ID=10393870

Family Applications (1)

Application Number Title Priority Date Filing Date
US764127A Expired - Lifetime US2909687A (en) 1957-11-28 1958-09-29 Cathode ray tubes

Country Status (4)

Country Link
US (1) US2909687A (fr)
DE (1) DE1126912B (fr)
FR (1) FR1205015A (fr)
GB (1) GB851757A (fr)

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3035197A (en) * 1958-11-21 1962-05-15 English Electric Valve Co Ltd Television camera tubes
US3060343A (en) * 1958-01-30 1962-10-23 Pye Ltd Television camera pick-up tubes
US3202857A (en) * 1960-08-30 1965-08-24 Rca Corp Mesh electrode support structure
US3237044A (en) * 1961-06-09 1966-02-22 Pye Ltd Pick-up tube target electrode assembly
US3309552A (en) * 1962-05-04 1967-03-14 Emi Ltd Non-magnetic metal mounting frame for pick-up tube targets for preventing microphony
US4155026A (en) * 1976-08-25 1979-05-15 English Electric Valve Company Limited Mesh electrodes
US4169986A (en) * 1976-08-16 1979-10-02 U.S. Philips Corporation Television camera tube having resilient gauze supporting structure
US4323814A (en) * 1980-05-16 1982-04-06 Rca Corporation Mesh assembly having reduced microphonics for a pick-up tube
US4366413A (en) * 1979-10-18 1982-12-28 Tokyo Shibaura Denki Kabushiki Kaisha Secondary electron multiplication target
US4857795A (en) * 1986-07-02 1989-08-15 Hitachi, Ltd. Internal magnetic shield support apparatus for color picture tube

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1014376A (en) * 1963-11-13 1965-12-22 English Electric Valve Co Ltd Improvements in or relating to television and like camera cathode ray tubes
DE1237168B (de) * 1965-08-17 1967-03-23 Fernseh Gmbh Verfahren und Vorrichtung zur Herstellung von mikrofoniefreien Speicherelektroden fuer Super-Orthikon-Roehren

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2617954A (en) * 1950-12-27 1952-11-11 Rca Corp Pickup tube

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NL227247A (fr) 1957-05-20

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2617954A (en) * 1950-12-27 1952-11-11 Rca Corp Pickup tube

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3060343A (en) * 1958-01-30 1962-10-23 Pye Ltd Television camera pick-up tubes
US3035197A (en) * 1958-11-21 1962-05-15 English Electric Valve Co Ltd Television camera tubes
US3202857A (en) * 1960-08-30 1965-08-24 Rca Corp Mesh electrode support structure
US3237044A (en) * 1961-06-09 1966-02-22 Pye Ltd Pick-up tube target electrode assembly
US3309552A (en) * 1962-05-04 1967-03-14 Emi Ltd Non-magnetic metal mounting frame for pick-up tube targets for preventing microphony
US4169986A (en) * 1976-08-16 1979-10-02 U.S. Philips Corporation Television camera tube having resilient gauze supporting structure
US4155026A (en) * 1976-08-25 1979-05-15 English Electric Valve Company Limited Mesh electrodes
US4366413A (en) * 1979-10-18 1982-12-28 Tokyo Shibaura Denki Kabushiki Kaisha Secondary electron multiplication target
US4323814A (en) * 1980-05-16 1982-04-06 Rca Corporation Mesh assembly having reduced microphonics for a pick-up tube
US4857795A (en) * 1986-07-02 1989-08-15 Hitachi, Ltd. Internal magnetic shield support apparatus for color picture tube

Also Published As

Publication number Publication date
GB851757A (en) 1960-10-19
FR1205015A (fr) 1960-01-29
DE1126912B (de) 1962-04-05

Similar Documents

Publication Publication Date Title
US2909687A (en) Cathode ray tubes
US3284655A (en) Cathode ray tube mesh assembly supported between envelope sections
US4341980A (en) Flat display device
GB726569A (en) Cathode-ray tube of the lenticular grill variety
US2923843A (en) Cathode ray tubes
US3293473A (en) Thin, porous storage phosphor layer
US3489966A (en) Cathode ray tube with stainless steel grid sealed into glass envelope
US2922907A (en) Target electrode assembly
US2547200A (en) Getter structure for electric discharge tubes
US2170663A (en) Electron discharge device
US3073981A (en) Photoconductive pickup tube having an electrically isolated mesh assembly
US2813224A (en) Color television picture tube
US2832911A (en) Thermal compensating grid frame
US5910703A (en) High voltage spacer for a flat panel display with specific cross section
US3188506A (en) Cathode ray tube with signal plate connected to contact ring having envelope diameter
US3320465A (en) Mesh with raster-size aperture for dampening vibrations of camera tube mesh
US3099762A (en) Cathode ray tube using replaceable cathode
US3197661A (en) Signal storage tubes
US3229141A (en) Television camera tube storage plate with rectangular stiffening ridge
US3497747A (en) High capacitance target structure for camera pick-up tube having dielectric sheet on metal mesh
US2939981A (en) Grid frame support structures for cathode ray tubes
JPS5838526Y2 (ja) 像増強装置
US3624442A (en) Individually hermetically sealed cathode-ray tubes connected by fiber optics array
US3035197A (en) Television camera tubes
US2978606A (en) Electron discharge device