Issued Patents 2004
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 6771075 | Air ion measuring device | Shunichi Takahashi | 2004-08-03 |
| 6768311 | Ion measuring device | Wakao Sakamoto | 2004-07-27 |
| 6703785 | Negative ion generator | Wakao Sakamoto | 2004-03-09 |