Issued Patents 1997
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5684785 | Optical disk and method of preventing fraudulent use of optical disk rotation synchronous control system | Kenichi Utsumi, Kazuo Nakashima, Kazunori Naito, Satoshi Komura | 1997-11-04 |
| 5623462 | Optical information recording/reproducing apparatus | Koichi Tezuka, Kyoko Miyabe, Tohru Fujimaki | 1997-04-22 |
| 5617393 | Optical disk having an erased-state indicator and optical disk apparatus for reducing frequency of disk erasing operation | Masaru Nakahara, Masahiro Nakada, Hiroshi Suzuki, Kenichi Utsumi | 1997-04-01 |