Issued Patents 1989
Showing 1–1 of 1 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4843461 | Over-door interphone system provided with a night-vision monitoring device | Yoshikazu Tatsumi | 1989-06-27 |
Showing 1–1 of 1 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4843461 | Over-door interphone system provided with a night-vision monitoring device | Yoshikazu Tatsumi | 1989-06-27 |