Issued Patents All Time
Showing 26–50 of 55 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5969876 | Projection lenses having large back focal length to focal length ratios | Melvyn H. Kreitzer | 1999-10-19 |
| 5969874 | Long focal length projection lenses | — | 1999-10-19 |
| 5870228 | Projection lenses having larger back focal length to focal length ratios | Melvyn H. Kreitzer | 1999-02-09 |
| 5841587 | LCD projection lens | — | 1998-11-24 |
| 5808804 | Projection television lens system | — | 1998-09-15 |
| 5745301 | Variable power lens systems for producing small images | Ellis I. Betensky, Melvyn H. Kreitzer | 1998-04-28 |
| RE35775 | Zoom lens with short back focal length | Ellis I. Betensky, Melvyn H. Kreitzer | 1998-04-21 |
| 5625495 | Telecentric lens systems for forming an image of an object composed of pixels | — | 1997-04-29 |
| 5559637 | Field curvature corrector | — | 1996-09-24 |
| RE35310 | Color corrected projection lens | — | 1996-08-06 |
| 5329363 | Projection lens systems having reduced spherochromatism | — | 1994-07-12 |
| 5296967 | High speed wide angle projection TV lens system | — | 1994-03-22 |
| 5268792 | Zoom lens | Melvyn H. Kreitzer | 1993-12-07 |
| 5218480 | Retrofocus wide angle lens | — | 1993-06-08 |
| 5200861 | Lens systems | — | 1993-04-06 |
| 4971428 | Catadioptric zoom lens | — | 1990-11-20 |
| 4963007 | Color corrected projection lens | — | 1990-10-16 |
| 4936661 | Zoom lens with short back focal length | Ellis I. Betensky, Melvyn H. Kreitzer | 1990-06-26 |
| 4776681 | Projection lens | — | 1988-10-11 |
| 4758073 | Zoom lens | — | 1988-07-19 |
| 4757372 | SLR zoom camera | Ellis I. Betensky, Melvyn H. Kreitzer | 1988-07-12 |
| 4755028 | Projection lens with an aspherical corrector lens element | — | 1988-07-05 |
| 4749268 | Autofocusing zoom lens | Ellis I. Betensky | 1988-06-07 |
| 4685774 | Projection lens | — | 1987-08-11 |
| 4682862 | Projection lens | — | 1987-07-28 |