IP Library › Granted Patent US 5,870,228
Granted Patent Utility
US 5,870,228 · App. 08/857,358

Projection lenses having larger back focal length to focal length ratios

Inventors: Melvyn H. Kreitzer, Jacob Moskovich
Patented Case View Patent ↗
Granted: Feb 9, 1999 Filed: May 16, 1997
Inventors
Melvyn H. Kreitzer
Jacob Moskovich
Assignee (at issue)
U.S. Precision Lens Incorporated

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Quick Facts
Patent No.
US 5,870,228
App. No.
08/857,358
Filed
1997-05-16
Granted
1999-02-09
Kind
A