IP Library › Granted Patent US 5,331,132
Granted Patent Utility
US 5,331,132 · App. 07/955,420

Manufacture of visual lenses

Inventors: Michael H. Freeman, Colin Maurice Perrott
Patented Case View Patent ↗
Granted: Jul 19, 1994 Filed: Oct 2, 1992
Inventors
Michael H. Freeman
Colin Maurice Perrott
Assignee (at issue)
Pilkington Diffractive Lenses Limited

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Quick Facts
Patent No.
US 5,331,132
App. No.
07/955,420
Filed
1992-10-02
Granted
1994-07-19
Kind
A