Issued Patents All Time
Showing 25 most recent of 28 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5989671 | Optical recording medium and manufacturing method thereof | Junichiro Nakayama, Hiroyuki Katayama, Akira Takahashi, Kenji Ohta | 1999-11-23 |
| 5981039 | Magnetic recording medium and a manufacturing method thereof as well as a photo-printing apparatus using such a magnetic recording medium | Hitoshi Isono | 1999-11-09 |
| 5754523 | Optical memory medium with preformed pit arrangement | Toshihisa Deguchi, Kenji Ohta, Akira Takahashi, Michinobu Mieda, Tetsuya Inui | 1998-05-19 |
| 5707754 | Magnetic recording medium and thermal recording printing device adopting the same | Hitoshi Isono | 1998-01-13 |
| RE35629 | Magneto-optical memory element | Yoshiteru Murakami, Akira Takahashi, Junichiro Nakayama, Hiroyuki Katayama, Kenji Ohta | 1997-10-14 |
| 5674583 | Optical recording medium and manufacturing method thereof | Junichiro Nakayama, Hiroyuki Katayama, Akira Takahashi, Kenji Ohta | 1997-10-07 |
| 5666345 | Optical memory medium with predetermined guide tracks and prepits | Akira Takahashi, Tetsuya Inui, Kenji Ohta, Toshihisa Deguchi | 1997-09-09 |
| 5605779 | Optical memory medium | Masahiro Irie | 1997-02-25 |
| 5500850 | Optical disk with grooves and pits of different depths | Kenji Ohta, Tetsuya Inui, Toshikazu Nagaura, Hirotoshi Takemori, Hirotaka Toki | 1996-03-19 |
| 5459711 | Optical recording element and driving system | Kenji Ohta, Tetsuya Inui, Hiroyuki Katayama, Akira Takahashi, Junji Hirokane +2 more | 1995-10-17 |
| 5457006 | Method of manufacturing photo-mask and photo-mask manufactured thereby | Junji Hirokane, Hiroyuki Katayama, Akira Takahashi, Tetsuya Inui, Kenji Ohta +3 more | 1995-10-10 |
| 5438561 | Method for recording and reproducing information using an optical memory | Kenji Ohta, Toshio Ishikawa | 1995-08-01 |
| 5403683 | Photo-mask | Kenji Ohta, Junji Hirokane, Akira Shibata, Yoshiyuki Nagahara, Michinobu Mieda +1 more | 1995-04-04 |
| 5399461 | Optical disk for use in optical memory devices | Kenji Ohta, Tetsuya Inui, Toshikazu Nagaura, Hirotoshi Takemori, Hirotaka Toki | 1995-03-21 |
| 5338646 | Optical memory device having an improved light reflection or optical memory layer | Junichiro Nakayama, Tomoyuki Miyake, Hiroyuki Katayama, Kenji Ohta | 1994-08-16 |
| 5335220 | Optical recording element and driving system | Kenji Ohta, Tetsuya Inui, Hiroyuki Katayama, Akira Takahashi, Junji Hirokane +2 more | 1994-08-02 |
| 5305254 | Magneto-optic memory device | Yoshiteru Murakami, Junichiro Nakayama, Ichiro Hiramatsu, Akira Takahashi, Kenji Ohta +1 more | 1994-04-19 |
| 5260150 | Photo-mask with light shielding film buried in substrate | Kenji Ohta, Junji Hirokane, Akira Shibata, Yoshiyuki Nagahara, Michinobu Mieda +1 more | 1993-11-09 |
| 5214636 | Optical recording element having a plurality of thin film filtering layers and optical recording element having an electrically conductive layer | Toshio Ishikawa, Hiroyuki Katayama, Tomoyuki Miyake, Junichiro Nakayama, Kenji Ohta +1 more | 1993-05-25 |
| 5192644 | Optical memory device | Kenji Ohta | 1993-03-09 |
| 5175079 | Optical memory device | Kenji Ohta, Yoshiteru Murakami | 1992-12-29 |
| 5170390 | Optical recording element and driving system | Kenji Ohta, Tetsuya Inui, Hiroyuki Katayama, Akira Takahashi, Junji Hirokane +2 more | 1992-12-08 |
| 5087535 | Method of manufacturing photo-mask and photo-mask manufactured thereby | Junji Hirokane, Hiroyuki Katayama, Akira Takahashi, Tetsuya Inui, Kenji Ohta +3 more | 1992-02-11 |
| 5088086 | Optical recording medium and the method of recording, reading, and erasing information using it | Hiroyuki Katayama, Akira Takahashi, Kenji Ohta | 1992-02-11 |
| 5081614 | Magneto-optical head utilizing central and peripheral portions of reflected light flux for different purposes | Akira Takahashi, Toshihisa Deguchi, Yoshiteru Murakami, Michinobu Mieda, Kenji Ohta +2 more | 1992-01-14 |