(19)

(11)

EP 0 929 827 A1

(12)

(43) Date of publication: 21.07.1999 Bulletin 1999/29 (21) Application number: 97942617.0 (22) Date of filing: 18.09.1997

(51) International Patent Classification (IPC):  G02B 1/ 10( . ) G02B 3/ 00( . ) G02B 1/ 00( . ) G02B 7/ 02( . ) (86) International application number: PCT/US1997/016726 (87) International publication number: WO 1998/014801 (09.04.1998 Gazette 1998/14)

(84) Designated Contracting States: DE FR GB NL (30) Priority: 30.09.1996 US 19960027117P (71) Applicant: CORNING INCORPORATED Corning, N.Y. 14831 (US)	(72) Inventor: GULATI, Suresh, T. Elmira Heights, NY 14903 (US) (74) Representative: Marchant, James Ian, et al  Elkington and Fife, Prospect House, 8 Pembroke Road Sevenoaks, Kent TN13 1XR Sevenoaks, Kent TN13 1XR (GB)