(19)

(11)

EP 0 819 291 A1

(12)

(43) Date of publication: 21.01.1998 Bulletin 1998/04 (21) Application number: 96908251.0 (22) Date of filing: 01.04.1996

(51) International Patent Classification (IPC):  G08B 13/ 196( . ) (86) International application number: PCT/GB1996/000773 (87) International publication number: WO 1996/031854 (10.10.1996 Gazette 1996/45)

(84) Designated Contracting States: DE ES FR GB IT (30) Priority: 01.04.1995 GB 19950006802 (71) Applicant: Meryon Instruments Limited Paisley PA1 3EQ (GB)	(72) Inventor: WILLIAMS, Simon, Rushbrook 46 Darvel Crescent Paisley PA1 3EQ (GB) (74) Representative: Pattullo, Norman, et al  Murgitroyd and Company 373 Scotland Street Glasgow G5 8QA Glasgow G5 8QA (GB)