(19)

(11)

EP 0 647 345 A1

(12)

(43) Date of publication: 12.04.1995 Bulletin 1995/15 (21) Application number: 93910629.0 (22) Date of filing: 22.04.1993

(51) International Patent Classification (IPC):  G02B 26/ 10( . ) G11B 7/ 09( . ) G11B 7/ 135( . ) G11B 7/ 003( . ) G11B 7/ 12( . ) G11B 7/ 14( . ) (86) International application number: PCT/US1993/003602 (87) International publication number: WO 1993/022765 (11.11.1993 Gazette 1993/27)

(84) Designated Contracting States: CH DE DK FR GB IT LI NL SE (30) Priority: 01.05.1992 US 19920877535 (71) Applicant: E-SYSTEMS INC. Dallas Texas 75240 (US)

(72) Inventors: BOARDMAN, John, D. Rockwall, Texas 75087 (US) HAMILTON, Scott, M. Rockwall, TX 75087 (US) GANGSTEAD, Mervin, L. Richardson, TX 75081 (US) SADLER, Jimmie, L. H 101 Boise, Idaho (US) TRIMBLE, Richard, A. Rowlett, TX 75088 (US) WELCH, Jeffrey, P. Libertyville, Illinois 60048 (US) (74) Representative: UEXKÜLL & STOLBERG  Patentanwälte Beselerstrasse 4 D-22607 Hamburg D-22607 Hamburg (DE)