Issued Patents 1989
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4864187 | Cathode for electron tube and manufacturing method thereof | Kinjiro Sano, Keiji Fukuyama, Masato Saito, Keiji Watanabe | 1989-09-05 |
| 4797593 | Cathode for electron tube | Masato Saito, Keiji Fukuyama, Masako Ishida, Keiji Watanabe, Kinjiro Sano | 1989-01-10 |