Issued Patents All Time
Showing 1–4 of 4 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 6062692 | Vision tester | Yoshikatsu Suzumura, Tetsu Tanigawa | 2000-05-16 |
| 4326281 | Mounting structure of plastic glass in watch case | Ryuzo Tanaka | 1982-04-20 |
| 4207735 | Dial and movement fixing structure | Ryuzo Tanaka | 1980-06-17 |
| 4186552 | Wristwatch case | Ryuzo Tanaka, Koichi Nakajima | 1980-02-05 |