Issued Patents All Time
Showing 1–4 of 4 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 6760945 | Acoustic toothbrush | Roman S. Ferber | 2004-07-13 |
| 4849841 | Transducer head core structure with recessed magnetic closures | — | 1989-07-18 |
| 4647994 | Miniaturized cartridge-type tape drive for data processors | Samuel N. Irwin, Francis Lum, Michael L. Bolt, Steven E. Henke, John M. Chambors | 1987-03-03 |
| 4646175 | Method and apparatus for positioning transducers by digital conversion of analog-type signals | Francis Lum | 1987-02-24 |