(19)

(11)

EP 0 909 375 A1

(12)

(43) Date of publication: 21.04.1999 Bulletin 1999/16 (21) Application number: 97929431.0 (22) Date of filing: 02.07.1997

(51) International Patent Classification (IPC):  G01J 3/ 02( . ) G01J 3/ 18( . ) (86) International application number: PCT/GB1997/001797 (87) International publication number: WO 1998/001729 (15.01.1998 Gazette 1998/02)

(84) Designated Contracting States: AT BE CH DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE (30) Priority: 04.07.1996 GB 19960014071 (71) Applicant: Spectrasense Ltd. Oxford OX2 0JX (GB)	(72) Inventors: ELLSMORE, Paul Alfred Oxford OX3 0LX (GB) HALLETT, William Andrew London SE1 7EQ (GB) SILVER, Joshua, David Oxford OX2 9HD (GB) (74) Representative: Flint, Adam, et al  W.H. Beck, Greener & Co., 7 Stone Buildings, Lincoln's Inn London WC2A 3SZ London WC2A 3SZ (GB)