US2523099A - Electric discharge tube comprising a directional electron beam - Google Patents

Electric discharge tube comprising a directional electron beam Download PDF

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Publication number
US2523099A
US2523099A US41364A US4136448A US2523099A US 2523099 A US2523099 A US 2523099A US 41364 A US41364 A US 41364A US 4136448 A US4136448 A US 4136448A US 2523099 A US2523099 A US 2523099A
Authority
US
United States
Prior art keywords
cathode
tube
wall
electron beam
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
US41364A
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English (en)
Inventor
Gier Johannes De
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 US2523099A publication Critical patent/US2523099A/en
Anticipated expiration legal-status Critical
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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
    • H01J29/06—Screens for shielding; Masks interposed in the electron stream

Definitions

  • the present invention relates to a device, the object of which is to raise th accelerating voltage to a considerable extent with unvaried diameter of atube.
  • the insulated wall portion over which the potential distribution occurs extends from the anode to beyond the cathode so that at the area of the electron-emissive surface of the cathode the wall exhibits a potential which is materially higher than that of the cathode; This is favour able for the production of irregular voltage divisions over the wall, which may bring aboutsliding-spark discharges and punctures'of the'wall.
  • the irregular voltage distribution and the sliding spark discharges are brought about by the modifi:
  • the cathode is secured to a cylindrical insulator which fits in theglass neckof the tube, that surface of the in V sulator which is adjacent the wall being'covcred-with an adhesive conductive layer "which'is either connected tothe cathode or provided with a lead-out conductor.
  • the conductor is adapted to be connected to anearthed have a particularly disadvantageous consequence if they produce a high field-intensity in the vicinityof the cathodej
  • the resulting forced discharge ofelectrons may cause an increase of the electron-emitting capacity of an oxide cathode such'that' the tube isithus rendered practically unserviceable.
  • Electrons which .come:,-'available upon suchelectron-emission phenomena! and which follow paths ending .on the :Wallof the 'tube may release secondary electrons at the surfaceoi thewall and thus bring about potential'differences'sufficiently high to initiate an electric spark-discharge, If the lines of force along which the electrons travel terminate on a screen arranged in'an insulated manner, this screen'will be charged in a negative sense, so that further supply of electrons cannot take place.
  • the screen may itself exhibit a shape'which is as edv ii se s as. d si sjfcr' int cold emission, since it doesnot f ulfila functionin the electrode system for generatingthe electron beam.
  • an electron-ray tube in which the electrode system is housed in the glass neck of the tube, the tube wall and that field electrode which is most adjacent the cathode are separated by.
  • a metal screen which extends from the wall in the space between the field electrodes and terminates therein and is connected in an electrically conductive manner to the conductive coating provided on the cathode insulator.
  • the electric charge supplied as a result of spark discharge is carried oil by the conductor connected to the conductive layer without any harmful efiect being possible.
  • the "glass wall I surrounds the electron-emitting cathode 2 and -the accelerating anode 3.
  • cathode 2 is secured to a cylindrical insulator 4 which fits in the glass neck of the tube and which may consist of ceramic material.
  • the anode 3 is clamped in position in the tube by means of resilient members 5.
  • a voltage difference of from 20,000'to 30,000 volts is applied between the cathode and the anode.
  • the insulating ring 4 also serves for the arrangement of the control electrode 6, to which a voltage is supplied which is adapted to vary between cathode potential and a negative value of a few hundred volts.
  • That surface of the ring 4 which is adjacent the wall of the tube is covered with an adhesive conductive layer 1 to which a supply conductor 8 is connected.
  • This negative conductor may be connected to an earthed point of the source of high-voltage supply.
  • the conductive layer exhibits the same potential as the control electrode.
  • the conductive layer maybe connected direct to the cathode as shown'in thedrawing.
  • Theanode voltage applied to the tube during operation is set up between the conductive layer 1 and a conductive coating H] which is provided on the wall of the tube and engaged by'clamping springs for supporting the anode 3.
  • a distribution of voltage along the wall of the tube which is as uniform as possible facilitates satisfactory operation of the tube and decreases therisk of disturbances. If, however, the wall of the tube is struck by electrons of, sufficient velocity t release secondary electrons, potential difierences may arise and lead to an increase of the voltage gradient along the surface of the wall.
  • A- resultant voltage discharge will find a way from the conductive coating H] to the other pole of the high-tension unit.
  • a metal screen 9 which extends from the wall in the space intermediate the field electrodes and terminates therein and is connected in an electrically conductive manner, to the conductive layer provided on the cathode insulator prevents the discharge from reaching the cathode.
  • the risk of irregular charge of the wall is considerably reduced by the provision of the conductive layer on the surface of the cathode insulator adjacent the wall and the connection thereof with an earthed point of the high-tension source, the presence of the screen substantially avoids any detrimental consequences of a discharge, since the electric charge is in this case carried ofi by the shortest route without being capable of provoking undue field intensities in the vicinity of the cathode.
  • An electric discharge device comprising an envelope having a tubular wall portion, a cathode source for generating a directional electron beam, first and second field electrodes within said envelope, a cylindrical insulating member interposed between said cathode source and said tubular envelope portion and fixedly securing said cathode source in spaced relation to said field electrodes, an adhesive electrically conducting layer interposed between said cylindrical member and said tubular envelope portion, and means to couple said conducting layer to said cathode.
  • An electric discharge device comprising an envelope having a tubular wall portion, a cathode source for generating a directional electron beam, first and second field electrodes within said envelope, a cylindrical insulating member interposed between said cathode source and said tubular envelope portion and fixedly securing said cathode source in spaced relation to said field electrodes, an adhesive electrically conducting layer interposed between said cylindrical memberand said tubular envelope portion and directly connected to said cathode source.
  • An electric discharge device comprising an envelope'having a tubular wall portion, a cathode source for generating a directional electron beam, first and second field electrodes within said envelope, a cylindrical insulating member interposed between said cathode source and said tubular envelope portion and fixedly securing said cathode source in spaced relation to said field electrodes, an adhesive electrically coducting layer interposed between said cylindrical member and said tubular envelope portion, means to couple said conducting layer to said cathode, and a metal screening member extending from the said wall portion and interposed between the said field electrodes, said screening member bein electrically connected to said conducting layer.

Landscapes

  • Vessels, Lead-In Wires, Accessory Apparatuses For Cathode-Ray Tubes (AREA)
  • Electrodes For Cathode-Ray Tubes (AREA)
  • Cathode-Ray Tubes And Fluorescent Screens For Display (AREA)
US41364A 1947-09-12 1948-07-29 Electric discharge tube comprising a directional electron beam Expired - Lifetime US2523099A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
NL655588X 1947-09-12

Publications (1)

Publication Number Publication Date
US2523099A true US2523099A (en) 1950-09-19

Family

ID=19795220

Family Applications (1)

Application Number Title Priority Date Filing Date
US41364A Expired - Lifetime US2523099A (en) 1947-09-12 1948-07-29 Electric discharge tube comprising a directional electron beam

Country Status (5)

Country Link
US (1) US2523099A (pt)
DE (1) DE814918C (pt)
FR (1) FR971541A (pt)
GB (1) GB655588A (pt)
NL (1) NL72660C (pt)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2701320A (en) * 1950-05-26 1955-02-01 Rca Corp Electron gun structure and method for making the same
US2727176A (en) * 1952-12-31 1955-12-13 Westinghouse Electric Corp Electrical discharge tube
US4585976A (en) * 1982-01-19 1986-04-29 Hewlett-Packard Company Beam penetration CRT with internal automatic constant deflection factor and pattern correction

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3034009A (en) * 1960-01-18 1962-05-08 Gen Electric Pin seal accelerator tubes

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2185807A (en) * 1937-04-30 1940-01-02 Gen Electric Cathode ray tube
GB519111A (en) * 1938-06-09 1940-03-18 Pye Ltd Improvements in and relating to cathode ray tubes
US2378569A (en) * 1940-03-29 1945-06-19 Messner Maximilian Cathode-ray tube
US2379488A (en) * 1943-10-08 1945-07-03 Du Mont Allen B Lab Inc Centering device for electron guns

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2185807A (en) * 1937-04-30 1940-01-02 Gen Electric Cathode ray tube
GB519111A (en) * 1938-06-09 1940-03-18 Pye Ltd Improvements in and relating to cathode ray tubes
US2378569A (en) * 1940-03-29 1945-06-19 Messner Maximilian Cathode-ray tube
US2379488A (en) * 1943-10-08 1945-07-03 Du Mont Allen B Lab Inc Centering device for electron guns

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2701320A (en) * 1950-05-26 1955-02-01 Rca Corp Electron gun structure and method for making the same
US2727176A (en) * 1952-12-31 1955-12-13 Westinghouse Electric Corp Electrical discharge tube
US4585976A (en) * 1982-01-19 1986-04-29 Hewlett-Packard Company Beam penetration CRT with internal automatic constant deflection factor and pattern correction

Also Published As

Publication number Publication date
FR971541A (fr) 1951-01-18
GB655588A (en) 1951-07-25
DE814918C (de) 1951-09-27
NL72660C (pt)

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