(19)

(11)

EP 0 495 068 A1

(12)

(43) Date of publication: 22.07.1992 Bulletin 1992/30 (21) Application number: 91914809.0 (22) Date of filing: 19.07.1991

(51) International Patent Classification (IPC):  H01J 9/ 24( . ) H01J 61/ 30( . ) H01J 5/ 02( . ) H01K 1/ 28( . ) (86) International application number: PCT/US1991/004997 (87) International publication number: WO 1992/002947 (20.02.1992 Gazette 1992/05)

(84) Designated Contracting States: AT DE FR GB IT SE (30) Priority: 03.08.1990 US 19900562251 (71) Applicants: LYNN, Judd B. Santa Rosa, CA 95405 (US) COLEMAN, William E. Colorado Springs, CO 80918 (US)	(72) Inventors: LYNN, Judd B. Santa Rosa, CA 95405 (US) COLEMAN, William E. Colorado Springs, CO 80918 (US) (74) Representative: Williams, John Francis  WILLIAMS, POWELL & ASSOCIATES 34 Tavistock Street London WC2E 7PB London WC2E 7PB (GB)