Issued Patents All Time
Showing 151–175 of 177 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 6078551 | Optical information recording or erasing system | Shinichi Tanaka, Mitsurou Moriya | 2000-06-20 |
| 6069860 | Optical head with objective lens having different numerical apertures to minimize light aberration with respect to optical disks of different thicknesses | Sadao Mizuno | 2000-05-30 |
| 5986779 | Multiple focus lens, an optical head apparatus and an optical information recording-reproducing apparatus | Yasuhiro Tanaka, Michihiro Yamagata, Sadao Mizuno | 1999-11-16 |
| 5920537 | Correction element of lower light intensity around an optical axis of an optical head with a plurality of focal points | Sadao Mizuno, Hideki Hayashi, Kenichiro Urairi | 1999-07-06 |
| 5912868 | Optical head for reproducing data from first and second optical disks | Hideki Hayashi, Sadao Mizuno, Noboru Ito, Kenichiro Urairi | 1999-06-15 |
| 5815293 | Compound objective lens having two focal points | Sadao Mizuno, Seiji Nishino | 1998-09-29 |
| 5757754 | Holographic optical head | Hiroaki Yamamoto, Tetsuo Saimi, Seiji Nishino, Hidenori Wada | 1998-05-26 |
| 5754512 | Correction elements to lower light intensity around an optical axis of an optical head with a plurality of focal points | Sadao Mizuno, Hideki Hayashi, Kenichiro Urairi | 1998-05-19 |
| 5748599 | Holographic optical device | Hiroaki Yamamoto, Tetsuo Saimi, Seiji Nishino, Hidenori Wada | 1998-05-05 |
| 5737296 | Focus and tracking error detection by using plus and minus first order diffracted light | Ken'ichi Kasazumi, Seiji Nishino, Hiroaki Yamamoto | 1998-04-07 |
| 5703856 | Optical head and optical data recording and reproducing apparatus having the same | Hideki Hayashi, Sadao Mizuno, Noboru Ito, Kenichiro Urairi | 1997-12-30 |
| 5687153 | Optical head device and optical information apparatus using a lithium niobate hologram with divisional areas to diffract light to corresponding photo detector areas | Seiji Nishino, Shin-ichi Kadowaki, Hiroaki Yamamoto, Makoto Kato, Tetsuo Saimi | 1997-11-11 |
| 5648951 | Movable optical head integrally incorporated with objective lens and hologram element | Makoto Kato, Shin-ichi Kadowaki, Yoshikazu Hori, Seiji Nishino, Tetsuo Saimi | 1997-07-15 |
| 5644413 | Optical head for adjusting a positional relation between the information medium and the optical head | Sadao Mizuno, Makoto Kato, Hidenori Wada, Seiji Nishino | 1997-07-01 |
| 5594713 | Optical pickup head apparatus | Seiji Nishino, Makoto Kato, Kaoru Matsuda | 1997-01-14 |
| 5502707 | Diffraction grating and optical pickup apparatus with diffracting grating | Seiji Nishino | 1996-03-26 |
| 5495461 | Optical pickup head apparatus | Seiji Nishino, Makoto Kato, Kaoru Matsuda | 1996-02-27 |
| 5446565 | Compound objective lens having two focal points | Sadao Mizuno, Seji Nishino | 1995-08-29 |
| 5412631 | Optical head apparatus for storing, reading or erasing information, and optical information reproducing method and optical information apparatus for optically reading information stored in an optical memory | Seiji Nishino, Makoto Kato | 1995-05-02 |
| 5400311 | Hologram and optical apparatus with hologram | Seiji Nishino | 1995-03-21 |
| 5345072 | Focus detection device for reading information from an optical recording medium | Hideki Hayashi, Shinichi Tanaka, Sadao Mizuno, Noboru Ito | 1994-09-06 |
| 5301182 | Optical pickup head | Seiji Nishino, Yoshikazu Hori | 1994-04-05 |
| 5296694 | Optical pick-up head apparatus with optical means having polarization anisotropy | Shin-ichi Kadowaki, Seiji Nishino, Hiroaki Yamamoto | 1994-03-22 |
| 5293038 | Optical pick-up head apparatus wherein hollographic optical element and photodetector are formed on semiconductor substrate | Shinichi Kadowaki, Seiji Nishino | 1994-03-08 |
| 5293367 | Optical pickup head wherein an error signal is produced by detecting a phase difference in diffraction beams from a holographic optical element | Shinichi Kadowaki, Naoyasu Miyagawa | 1994-03-08 |