(19)

(11)

EP 0 224 575 A1

(12)

(43) Date of publication: 10.06.1987 Bulletin 1987/24 (21) Application number: 86903974.0 (22) Date of filing: 04.06.1986

(51) International Patent Classification (IPC):  G01L 9/ 00( . ) (86) International application number: PCT/US1986/001232 (87) International publication number: WO 1986/007445 (18.12.1986 Gazette 1986/27)

(84) Designated Contracting States: AT BE CH DE FR GB IT LI LU NL SE (30) Priority: 04.06.1985 US 19850740996 (71) Applicant: OPTIMA SYSTEMS, INC. Burlington Massachusetts 01803 (US)	(72) Inventors: HOFFMAN, Robert, W. Arlington, MA 02174 (US) EKCHIAN, Jack, A. Watertown, MA 02172 (US) EKCHIAN, Leon Woodland Hills, CA 91367 (US)