(19)

(11)

EP 0 664 072 A1

(12)

(43) Date of publication: 26.07.1995 Bulletin 1995/30 (21) Application number: 94923013.0 (22) Date of filing: 05.08.1994

(51) International Patent Classification (IPC):  H01J 37/ 32( . ) H01S 3/ 0975( . ) H01S 3/ 03( . ) H05H 1/ 46( . ) (86) International application number: PCT/GB1994/001722 (87) International publication number: WO 1995/005060 (16.02.1995 Gazette 1995/08)

(84) Designated Contracting States: DE FR GB (30) Priority: 05.08.1993 GB 19930016282 (71) Applicant: LUMONICS LIMITED Hull, North Humberside HU7 OYE (GB)	(72) Inventors: BAKER, Howard, John Midlothian EH14 5TL (GB) COLLEY, Alan, David Edinburgh EH14 5BU (GB) HALL, Denis, Roderick Musselburgh EH21 7TD (GB) (74) Representative: Walker, Antony James Alexander, et al  W.P. Thomson & Co., Kings Building, South Church Side Hull, HU1 1RR Hull, HU1 1RR (GB)