(19)

(11)

EP 0 168 462 A1

(12)

(43) Date of publication: 22.01.1986 Bulletin 1986/04 (21) Application number: 85900777.0 (22) Date of filing: 16.01.1985

(51) International Patent Classification (IPC):  G01B 7/ 00( . ) (86) International application number: PCT/NL1985/000004 (87) International publication number: WO 1985/003346 (01.08.1985 Gazette 1985/17)

(84) Designated Contracting States: CH DE FR GB LI NL SE (30) Priority: 18.01.1984 NL 19840000169 (71) Applicant: STICHTING CENTRUM VOOR MICRO-ELEKTRONICA TWENTE NL-7521 PA Enschede (NL)	(72) Inventor: GROENLAND, Johannes, Petrus, Jacobus NL-7555 KX Hengelo (NL)