Issued Patents All Time
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5255334 | Directional coupler type optical device and a driving method therefor | Hisaharu Yanagawa | 1993-10-19 |
| 5146518 | Optical directional coupler device and a method of driving same | Hisaharu Yanagawa | 1992-09-08 |