Issued Patents 1989
Showing 1–6 of 6 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4864423 | Information recording disc and information signal recording apparatus therefor | Tadao Nagai, Hirohisa Yamaguchi | 1989-09-05 |
| 4841504 | Method and apparatus for recording an information signal on a rotary recording medium | Hirohisa Yamaguchi | 1989-06-20 |
| 4813034 | Optical disc recording apparatus with a light beam having a controllable quantity | — | 1989-03-14 |
| 4803677 | Rotary recording medium having a guide track and recording and reproducing apparatus therefor | Hirohisa Yamaguchi, Horoshi Usami, Tadao Nagai | 1989-02-07 |
| 4802159 | Information recording disc and information signal recording apparatus therefor | Tadao Nagai, Hirohisa Yamaguchi | 1989-01-31 |
| 4796097 | Optical disc recording apparatus for a color television signal | — | 1989-01-03 |