Issued Patents All Time
Showing 26–38 of 38 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4891305 | Optical information recording element | Hideaki Oba, Tsutomu Sato, Masaakira Umehara, Yutaka Ueda, Tetsu Yamamuro | 1990-01-02 |
| 4829499 | Processing of a detection signal obtained by scanning an optical disk | — | 1989-05-09 |
| 4767693 | Optical information recording medium | Hideaki Oba, Yutaka Ueda, Tsutomu Sato, Masaakira Umehara, Hitoshi Funakoshi +1 more | 1988-08-30 |
| 4758499 | Optical information recording medium | Tsutomu Sato, Hideaki Oba, Masaakira Umehara, Yutaka Ueda, Tetsu Yamamuro | 1988-07-19 |
| 4714667 | Optical information recording medium | Tsutomu Sato, Masaakira Umehara, Hideaki Oba, Yutaka Ueda | 1987-12-22 |
| 4696892 | Optical information recording medium | Masaakira Umehara, Tsutomu Sato, Hideaki Oba, Yutaka Ueda, Makoto Kunikane | 1987-09-29 |
| 4656121 | Optical information recording medium | Tsutomu Sato, Masaakira Umehara, Hideaki Oba, Yutaka Ueda | 1987-04-07 |
| 4652514 | Optical information recording medium | Hideaki Oba | 1987-03-24 |
| 4600625 | Optical information recording medium | Hideaki Oba | 1986-07-15 |
| 4525625 | Focussing control with astigmatic diffracting means | — | 1985-06-25 |
| 4477555 | Optical information recording medium | Hideaki Oba, Makoto Kunikane, Masaakira Umehara, Kiyoshi Tanikawa | 1984-10-16 |
| 4460665 | Optical information recording medium | Makoto Kunikane, Masaakira Umehara | 1984-07-17 |
| 4225211 | Random phase plate for holography and process for manufacturing same | — | 1980-09-30 |