(19)
(11) EP 0 957 505 A3

(12) EUROPEAN PATENT APPLICATION

(88) Date of publication A3:
31.07.2002 Bulletin 2002/31

(43) Date of publication A2:
17.11.1999 Bulletin 1999/46

(21) Application number: 99303558.3

(22) Date of filing: 06.05.1999
(51) International Patent Classification (IPC)7: H01J 21/10, H01J 3/02
(84) Designated Contracting States:
AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE
Designated Extension States:
AL LT LV MK RO SI

(30) Priority: 09.05.1998 GB 9809819

(71) Applicant: EEV LIMITED
Chelmsford, Essex, CM1 2QU (GB)

(72) Inventors:
  • Bardell, Steven
    Barnston, Nr. Great Dunmow Essex CM6 1NF (GB)
  • Thwaites, Alfred Christopher
    Maldon, Essex CM9 6YW (GB)

(74) Representative: Cockayne, Gillian 
Marconi Intellectual Property Marrable House The Vineyards Gt. Baddow
Chelmsford Essex CM2 7QS
Chelmsford Essex CM2 7QS (GB)

   


(54) Electron gun assembly


(57) An electron gun assembly includes a cathode 1, control grid 5 located in front of it and a focus electrode 6. The control electrode 5 is integral with a cylindrical support 11 and formed of pyrolytic graphite. Similarly, the focus electrode 6 is integral with a cylindrical support 16 and is formed of molybdenum. The control grid 5 and focus electrode 6 are mounted on a common mount 15 located behind the front face of the cathode 1, giving a simple structure having low thermally capacity and being mechanically robust.






Search report