(19)

(11)

EP 0 051 610 A1

(12)

(43) Date of publication: 19.05.1982 Bulletin 1982/20 (21) Application number: 81901122.0 (22) Date of filing: 08.05.1981

(51) International Patent Classification (IPC):  G02B 6/ 38( . ) (86) International application number: PCT/SE1981/000137 (87) International publication number: WO 1981/003227 (12.11.1981 Gazette 1981/27)

(84) Designated Contracting States: CH DE FR GB LI NL (30) Priority: 09.05.1980 SE 19800003509 (71) Applicant: LIDHOLT, Lars Rune S-752 45 Uppsala (SE)	(72) Inventor: LIDHOLT, Lars Rune S-752 45 Uppsala (SE)