(19)

(11)

EP 0 963 551 A1

(12)

(43) Date of publication: 15.12.1999 Bulletin 1999/50 (21) Application number: 98907482.0 (22) Date of filing: 17.02.1998

(51) International Patent Classification (IPC):  G01N 30/ 84( . ) (86) International application number: PCT/US1998/002983 (87) International publication number: WO 1998/038507 (03.09.1998 Gazette 1998/35)

(84) Designated Contracting States: AT BE CH DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE Designated Extension States: AL LT LV MK RO SI (30) Priority: 28.02.1997 US 19970807329 (71) Applicant: ANTEK INSTRUMENTS, INC. Houston, TX 77090-3508 (US)	(72) Inventors: WREYFORD, Randy, L. Spring, TX 77389 (US) BORNY, Jean-François Crosby, TX 77532 (US) (74) Representative: W.P. Thompson & Co.  Coopers Building, Church Street Liverpool L1 3AB Liverpool L1 3AB (GB)