(19)

(11)

EP 0 613 539 A1

(12)

(43) Date of publication: 07.09.1994 Bulletin 1994/36 (21) Application number: 92923435.0 (22) Date of filing: 13.11.1992

(51) International Patent Classification (IPC):  G03B 17/ 56( . ) F16M 13/ 04( . ) F16M 13/ 00( . ) G02B 23/ 16( . ) (86) International application number: PCT/GB1992/002100 (87) International publication number: WO 1993/010390 (27.05.1993 Gazette 1993/13)

(84) Designated Contracting States: AT BE DE DK FR GB IT NL SE (30) Priority: 21.11.1991 GB 19910024710 (71) Applicant: THE SECRETARY OF STATE FOR DEFENCE IN HER BRITANNIC MAJESTY'S GOVERNMENT OF THE UNITED KINGDOM OF GREAT BRITAIN AND Hampshire GU14 6TD (GB)	(72) Inventor: McGILL, Keith Robert Erith, Kent DA5 1EJ (GB) (74) Representative: Beckham, Robert William, et al  Defence Research Agency Intellectual Property Department DRA Farnborough R69 Building Farnborough, Hants. GU14 6TD Farnborough, Hants. GU14 6TD (GB)