(19)

(11)

EP 0 513 025 A1

(12)

(43) Date of publication: 19.11.1992 Bulletin 1992/47 (21) Application number: 91901881.0 (22) Date of filing: 28.12.1990

(51) International Patent Classification (IPC):  G01N 21/ 65( . ) G07D 7/ 12( . ) G02B 26/ 00( . ) G07D 7/ 20( . ) (86) International application number: PCT/GB1990/002032 (87) International publication number: WO 1991/011703 (08.08.1991 Gazette 1991/18)

(84) Designated Contracting States: AT BE CH DE DK ES FR GB GR IT LI NL SE (30) Priority: 02.02.1990 GB 19900002335 (71) Applicant: THOMAS DE LA RUE & COMPANY LIMITED London WC2N 4DE (GB)	(72) Inventors: BRATCHLEY, Robin Reading, Berkshire RG5 4TT (GB) BATCHELDER, David, Neville London E9 7AT (GB) (74) Representative: Perry, Robert Edward  GILL JENNINGS & EVERY Broadgate House 7 Eldon Street London EC2M 7LH London EC2M 7LH (GB)