(19)

(11)

EP 0 177 541 A1

(12)

(43) Date of publication: 16.04.1986 Bulletin 1986/16 (21) Application number: 85901532.0 (22) Date of filing: 12.04.1985

(51) International Patent Classification (IPC):  G06K 7/ 08( . ) G07F 7/ 02( . ) G06K 13/ 07( . ) (86) International application number: PCT/GB1985/000164 (87) International publication number: WO 1985/004969 (07.11.1985 Gazette 1985/24)

(84) Designated Contracting States: AT BE CH DE FR GB IT LI LU NL SE (30) Priority: 18.04.1984 GB 19840010098 (71) Applicant: GEC TRAFFIC AUTOMATION LIMITED Borehamwood Hertfordshire WD6 1RX (GB)	(72) Inventors: COMBEN, Peter, Alan Ruislip Middlesex HA4 9QE (GB) JERVIS, Edward, Richard Luton, Bedfordshire LU2 7AN (GB) STANFORD, Christopher, John Hertfordshire AL5 3BW (GB)