(19)

(11)

EP 0 243 399 A1

(12)

(43) Date of publication: 04.11.1987 Bulletin 1987/45 (21) Application number: 86906073.0 (22) Date of filing: 15.09.1986

(51) International Patent Classification (IPC):  H01J 9/ 24( . ) H01J 23/ 26( . ) (86) International application number: PCT/US1986/001889 (87) International publication number: WO 1987/002507 (23.04.1987 Gazette 1987/09)

(84) Designated Contracting States: DE FR GB IT (30) Priority: 21.10.1985 US 19850789882 (71) Applicant: Hughes Aircraft Company Los Angeles California 90045-0066 (US)	(72) Inventor: LEE, George, M. Redondo Beach, CA 90277 (US) (74) Representative: KUHNEN, WACKER & PARTNER  Alois-Steinecker-Strasse 22 D-85354 Freising D-85354 Freising (DE)