Large area directly heated lanthanum hexaboride cathode structure having predetermined emission profile

Title: Large area directly heated lanthanum hexaboride cathode structure having predetermined emission profile

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Abstract

A large area directly heated lanthanum hexaboride (LaB/sub 6/) cathode system is disclosed. The system comprises a LaB/sub 6/ cathode element generally circular in shape about a central axis. The cathode element has a head with an upper substantially planar emission surface, and a lower downwardly and an intermediate body portion which diminishes in cross-section from the head towards the base of the cathode element. A central rod is connected to the base of the cathode element and extends along the central axis. Plural upstanding spring fingers are urged against an outer peripheral contact surface of the head end to provide a mechanical and electrical connection to the cathode element. 7 figs

Inventors:: Leung, Ka-Ngo; Gordon, K.C.; Kippenhan, D.O.; Purgalis, P.; Moussa, D.; Williams, M.D.; Wilde, S.B.; West, M.W.

Issue Date:: 1987-10-16

Research Org.:: Lawrence Berkeley Lab., CA (USA)

OSTI Identifier:: 6682795

Patent Number(s):: -US-A6108327

Application Number:: ON: DE89000184

Assignee:: LBNL; ERA-14-003724; EDB-88-195598

DOE Contract Number:: AC03-76SF00098

Resource Type:: Patent

Resource Relation:: Other Information: Portions of this document are illegible in microfiche products

Country of Publication:: United States

Language:: English

Subject:: 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 36 MATERIALS SCIENCE; CATHODES; DESIGN; LANTHANUM BORIDES; SURFACE AREA; CHEMICAL PROPERTIES; ELECTRON EMISSION; INVENTIONS; PHYSICAL PROPERTIES; THERMIONIC EMITTERS; BORIDES; BORON COMPOUNDS; ELECTRODES; EMISSION; LANTHANUM COMPOUNDS; RARE EARTH COMPOUNDS; SURFACE PROPERTIES 640301* -- Atomic, Molecular & Chemical Physics-- Beams & their Reactions; 360204 -- Ceramics, Cermets, & Refractories-- Physical Properties

Citation Formats


                    Leung, Ka-Ngo, Gordon, K.C., Kippenhan, D.O., Purgalis, P., Moussa, D., Williams, M.D., Wilde, S.B., and West, M.W. Large area directly heated lanthanum hexaboride cathode structure having predetermined emission profile.  United States: N. p., 1987. 
        Web.

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                    Leung, Ka-Ngo, Gordon, K.C., Kippenhan, D.O., Purgalis, P., Moussa, D., Williams, M.D., Wilde, S.B., & West, M.W. Large area directly heated lanthanum hexaboride cathode structure having predetermined emission profile.  United States.

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                    Leung, Ka-Ngo, Gordon, K.C., Kippenhan, D.O., Purgalis, P., Moussa, D., Williams, M.D., Wilde, S.B., and West, M.W. Fri .  
        "Large area directly heated lanthanum hexaboride cathode structure having predetermined emission profile".  United States.

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@article{osti_6682795,

  title        = {Large area directly heated lanthanum hexaboride cathode structure having predetermined emission profile},

  author       = {Leung, Ka-Ngo and Gordon, K.C. and Kippenhan, D.O. and Purgalis, P. and Moussa, D. and Williams, M.D. and Wilde, S.B. and West, M.W.},

  abstractNote = {A large area directly heated lanthanum hexaboride (LaB/sub 6/) cathode system is disclosed. The system comprises a LaB/sub 6/ cathode element generally circular in shape about a central axis. The cathode element has a head with an upper substantially planar emission surface, and a lower downwardly and an intermediate body portion which diminishes in cross-section from the head towards the base of the cathode element. A central rod is connected to the base of the cathode element and extends along the central axis. Plural upstanding spring fingers are urged against an outer peripheral contact surface of the head end to provide a mechanical and electrical connection to the cathode element. 7 figs},

  doi          = {},

  journal      = {},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {1987},

  month        = {10}

}

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Large area directly heated lanthanum hexaboride cathode structure having predetermined emission profile

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