Issued Patents All Time
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 6801635 | Speaker device | Hideki Minami, Toshio Hirosawa | 2004-10-05 |
| 6493452 | Speaker unit | Hiroshi Koizumi, Hideki Minami | 2002-12-10 |
| 5521886 | Diaphragm for use with an electro-acoustic transducer and method of producing the same | Toshio Hirosawa, Hiroshi Koizumi, Itaru Tanaka | 1996-05-28 |