Issued Patents All Time
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5117463 | Speaker system having directivity | Takashi Oyaba, Hideaki Morikawa, Yasuo Gan | 1992-05-26 |
| 4991687 | Speaker system having directivity | Takashi Oyaba, Hideaki Morikawa, Yasuo Gan | 1991-02-12 |