[go: up one dir, main page]

US2167097A - Secondary electron discharge device - Google Patents

Secondary electron discharge device Download PDF

Info

Publication number
US2167097A
US2167097A US160796A US16079637A US2167097A US 2167097 A US2167097 A US 2167097A US 160796 A US160796 A US 160796A US 16079637 A US16079637 A US 16079637A US 2167097 A US2167097 A US 2167097A
Authority
US
United States
Prior art keywords
anode
electrode
cathode
electron
aperture
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
US160796A
Other languages
English (en)
Inventor
Adrianus J W M Van Overbeek
Edmund H Lopp
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.)
Koninklijke Philips NV
Original Assignee
Philips Gloeilampenfabrieken NV
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 Philips Gloeilampenfabrieken NV filed Critical Philips Gloeilampenfabrieken NV
Application granted granted Critical
Publication of US2167097A publication Critical patent/US2167097A/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
    • H01J43/00—Secondary-emission tubes; Electron-multiplier tubes
    • H01J43/02—Tubes in which one or a few electrodes are secondary-electron emitting electrodes

Definitions

  • This invention relates to an electron discharge tube having an electrode system including a secondary electron emission electrode or emitter with a surface having such properties that on being struck by a primary electron a plurality of secondary electrons emerge from it, so that the ratio of the number of secondary electrons to the number of primary electrons is greater than unity.
  • Tubes of the type referred to have been used with satisfactory results, but i'n'certain cases difficulties arise because an increase in anode voltage causes an excessive increase in anode current, resulting, for example, in a reduction of the interal resistance, which may be objectionable in the operation of the tube.
  • ' 'I'heprincipal object of the invention is to provide an improved tube of the type referred to in l which diificulties due to excessive increase of output current with increase of anode voltage are'avoided.
  • a discharge tube with an electrode system so constructed that electrons emerging from the cathode are united to form one or more beams, has the anode out of the path of the primary electron beam and the secondary emission electrode is coated on only part of its'surface with a substance which is capable of emitting secondary electrons.
  • the tube become wider or narrower as the anode voltage increases or decreases, so that the part of the secondary emission electrode which 'is coated with a substance readily emitting secondary electrons is struck to agreater or less extent by the primary electrons.
  • the anode is in the path of and can be' struck as the anode voltage increases or decreases, a
  • the edge of .the secondary emission electrode is not entirely parallel to the edge of the electron beam or is not symmetrical to this beam.
  • the edge of the secondary emission electrode may, for example, be notched; the edge of the electron emitting layer on this electrode may be indented; or the electrode 'may be arranged asymmetrically in the tube; the effect of which 'may also be obtained by making the beam or beams asymmetrical t0 the remainder of the tube, for example, by using beam forming electrodes of a suitable construction.
  • the tube shown in Figure 1 comprises a rectilinear cathode I, such as an indirectly heated cathode, and a control electrodeformed by four" straight rods 2 parallelto the cathode and equally spaced about the cathode. These rods are connected to constitute an equipotential grid.
  • This electrode struc ture concentrates the discharge from the cathode into four radial beams which emerge from, the spaces between the slats 3.
  • FIG 2 a modification having a control grid I: of the conventional wound grid type, a duplex accelerating electrode l3 comprising two parallel metal sheets mounted on opposite sides of the control grid and connected together, and an anode comprising four parallel flat members ll arranged in two pairs, each pair mounted beyond the ends of the accelerating electrode II and spaced at a distance at least as great as the spacing between the accelerating electrode sheets ii.
  • the accelerating electrode forms the discharge from the cathode into two diametrically opposite beams which emerge from opposite ends of the accelerating electrode. Each beam passes through the space between the corresponding pair of anode members.
  • the beam on widening and narrowing strikes more or less that part of the secondary emission electrode outside the edges of the part It which is not coated with the substance that readily emits secondary electrons.
  • Figures 3 and 4 show modifications in the shape of the secondary electron emitter II.
  • such an electrode or emitter which may be of various shapes and sizes, comprises a metal sheet with the edge which corresponds to a straight side of the aperture in the output anode made irregular, for example by notches or indentations II in the edge.
  • the secondary electron emission is less than in the case where the edge is straight.
  • the secondary electron emitter is a fiat sheet wider at the upper than at the lower end, so that for a part of its length the electrode is narrower than the aperture in the output anode.
  • An electron discharge tube comprising an electrode system including a cathode, an output anode having an aperture, a beam forming electrode between said cathode and said output anode for concentrating the discharge from said cathode to said output anode into an electron beam directed through said aperture in said anode, and a second anode element further from said cathode than said output anode and extending transversely of the axis of the electron beam, said second anode element being wider than said aperture and having opposite said aperture a sur- 1 face of high secondary electron emissivity which is narrower than said aperture in said output anode and is within the projection of said aperture on the planeof said second anode element.

Landscapes

  • Discharge Lamp (AREA)
  • Cold Cathode And The Manufacture (AREA)
US160796A 1936-09-01 1937-08-25 Secondary electron discharge device Expired - Lifetime US2167097A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
NL201099X 1936-09-01

Publications (1)

Publication Number Publication Date
US2167097A true US2167097A (en) 1939-07-25

Family

ID=19778338

Family Applications (1)

Application Number Title Priority Date Filing Date
US160796A Expired - Lifetime US2167097A (en) 1936-09-01 1937-08-25 Secondary electron discharge device

Country Status (5)

Country Link
US (1) US2167097A (zh)
BE (1) BE423376A (zh)
CH (1) CH201099A (zh)
GB (1) GB496705A (zh)
NL (1) NL47224C (zh)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2528437A (en) * 1945-08-04 1950-10-31 Ivan L Joy Multiple anode tube and method of employing the same in testing apparatus
US2553997A (en) * 1948-01-24 1951-05-22 Emi Ltd Thermionic valve utilizing secondary electron emission amplification

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2528437A (en) * 1945-08-04 1950-10-31 Ivan L Joy Multiple anode tube and method of employing the same in testing apparatus
US2553997A (en) * 1948-01-24 1951-05-22 Emi Ltd Thermionic valve utilizing secondary electron emission amplification

Also Published As

Publication number Publication date
NL47224C (zh)
BE423376A (zh)
CH201099A (de) 1938-11-15
GB496705A (en) 1938-12-05

Similar Documents

Publication Publication Date Title
US2245605A (en) Electron multiplier
GB978223A (en) Voltage indicator tube having two indicator systems
US2254095A (en) Electron beam discharge device
US4583021A (en) Electron gun with improved cathode and shadow grid configuration
US2167097A (en) Secondary electron discharge device
US2163966A (en) Box element multiplier
US2144085A (en) Electron discharge tube
US2200722A (en) Electron discharge device
US2173267A (en) Electron discharge device
US2005330A (en) Electron emission device
US2617959A (en) Electron discharge device
US2340631A (en) Secondary electron amplifier
US2173165A (en) Electron tube
US2176599A (en) Electron beam tube
US2151783A (en) Secondary electron discharge tube
US2225786A (en) Secondary emitting tube
US1659636A (en) Device fob amplifying voltage and cubeent
US2246172A (en) Electron multiplier tube
US2225325A (en) Electron discharge device
US2564743A (en) Charged particle beam forming apparatus
US1612835A (en) Intermediate electrode in incandescent cathode tube
US2134407A (en) Electron discharge device
US2171214A (en) Secondary electron emitting screen tube
US2932754A (en) Electron tubes
US2018362A (en) Electron discharge tube