(19)

(11)

EP 0 642 659 A1

(12)

(43) Date of publication: 15.03.1995 Bulletin 1995/11 (21) Application number: 94909989.0 (22) Date of filing: 21.03.1994

(51) International Patent Classification (IPC):  A61B 18/ 20( . ) H04B 10/ 08( . ) G01M 11/ 00( . ) (86) International application number: PCT/GB1994/000571 (87) International publication number: WO 1994/021997 (29.09.1994 Gazette 1994/22)

(84) Designated Contracting States: DE GB (30) Priority: 24.03.1993 GB 19930006090 (71) Applicant: BT&D TECHNOLOGIES LTD. Bracknell, Berkshire RG12 1HN (GB)	(72) Inventors: SIMMONS, Timothy, John 27 Blackbourne Road Suffolk IP30 9UH (GB) HARKER, Andrew, Thomas 43 Clarkson Street Suffolk IP1 2JN (GB) FAKE, Michael 85 Mumford Road West Bergholt Essex CO6 3BN (GB) (74) Representative: Webster, Denise Mary  Hewlett-Packard Ltd, IP Section, Building 2, Filton Road, Stoke Gifford Bristol BS12 6QZ Bristol BS12 6QZ (GB)