Issued Patents All Time
Showing 1–24 of 24 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 6985487 | Broadband switching networks | Hiroshi Kobayashi, Yoshiharu Hidaka, Takashi Ikeda, Motomitsu Yano, Kouichirou Kamura | 2006-01-10 |
| 6297902 | Light amplification medium control method, light amplification apparatus and system using the same | Junya Kosaka, Shinji Sakano, Yoshiaki Sato | 2001-10-02 |
| 6219349 | Broadband switching networks | Hiroshi Kobayashi, Yoshiharu Hidaka, Takashi Ikeda, Motomitsu Yano, Kouichirou Kamura | 2001-04-17 |
| 6172803 | Optical amplifier and transmission system using the same | Hiroji Masuda, Shingo Kawai, Kenichi Suzuki | 2001-01-09 |
| 6157025 | Disk shaped tunable optical filter | Yoshitada Katagiri, Yoshiaki Tachikawa, Shinji Nagaoka, Fumikazu Ohira, Ken Suzuki +3 more | 2000-12-05 |
| 6122087 | Optical-frequency-stabilized light source | Seiji Nogiwa, Tatsuhiko Takatsu, Naoto Sato, Hiroji Masuda | 2000-09-19 |
| 5896371 | Broadband switching networks | Hiroshi Kobayashi, Yoshiharu Hidaka, Takashi Ikeda, Motomitsu Yano, Kouichirou Kamura | 1999-04-20 |
| 5825766 | Broadband switching networks | Hiroshi Kobayashi, Yoshiharu Hidaka, Takashi Ikeda, Motomitsu Yano, Kouichirou Kamura | 1998-10-20 |
| 5786930 | Optical frequency sweep signal generator | Tatsuhiko Takatsu, Kiyoshi Nakagawa | 1998-07-28 |
| 5781322 | Method and apparatus for measuring the noise figure of an optical amplifier | Haruyoshi Uchiyama, Zhixien Li | 1998-07-14 |
| 5677781 | Method and device for measuring a noise figure in optical amplifiers | Tohru Mori | 1997-10-14 |
| 5633750 | Optical fiber amplifier | Seiji Nogiwa, Kiyoshi Nakagawa | 1997-05-27 |
| 5596441 | Optical polarization controller | Nobuhiro Sakakibara, Kiyoshi Nakagawa | 1997-01-21 |
| 5574534 | Apparatus for determining noise factor of optical amplifier | Seiji Nogiwa, Kiyoshi Nakagawa | 1996-11-12 |
| 5561551 | Method and apparatus for determining noise factor of optical amplifier | Takashi Iwasaki, Haruyoshi Uchiyama, Yoshiaki Sato | 1996-10-01 |
| 5521751 | Noise measurement for optical amplifier and a system therefor | Yoshiaki Sato | 1996-05-28 |
| 5495362 | Photoperiodic circuit amplification control apparatus | Tatuhiko Takatu, Kiyoshi Nakagawa | 1996-02-27 |
| 5493573 | Broad band switching network | Hiroshi Kobayashi, Kunihiko Sekiya, Yoshihiro Hidaka, Michiaki Okano, Shigenobu Minami +4 more | 1996-02-20 |
| 5475529 | Optical amplifier | Tatuhiko Takatu, Kiyoshi Nakagawa | 1995-12-12 |
| 5471334 | Method and apparatus for monitoring noise figure of optical amplifier | Hiroji Masuda, Kiyoshi Nakagawa | 1995-11-28 |
| 5245690 | Optical fiber amplifier including rare earth doped fiber and feedback pump light source control | Hiroji Masuda, Kiyoshi Nakagawa | 1993-09-14 |
| 5083874 | Optical repeater and optical network using the same | Shigendo Nishi, Masatoshi Saruwatari, Kiyoshi Nakagawa | 1992-01-28 |
| 5021948 | Program counter display device | Yasuko Nakayama | 1991-06-04 |
| 5005937 | Optical branching equipment and optical network using the same | Shigendo Nishi, Kiyoshi Nakagawa | 1991-04-09 |