(19)

(11)

EP 1 076 815 A1

(12)

(43) Date of publication: 21.02.2001 Bulletin 2001/08 (21) Application number: 00913762.1 (22) Date of filing: 03.03.2000

(51) International Patent Classification (IPC)7: G01N 21/64 (86) International application number: PCT/US0005/839 (87) International publication number: WO 0052/452 (08.09.2000 Gazette 2000/36)

(84) Designated Contracting States: AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE (30) Priority: 05.03.1999 US 122913 P (71) Applicant: Yellow Springs Optical Sensor Co. PLL. Yellow Springs, OH 45387 (US)	(72) Inventor: LUSSIER, Jamie, N. Huber Heights, OH 45424 (US) (74) Representative: Bankes, Stephen Charles Digby et al BARON & WARREN18 South EndKensington London W8 5BU London W8 5BU (GB)