1
Hiroshi Onaka, Hideyuki Miyata, Kazue Otsuka, Yutaka Kai, Tadao Nakazawa, Terumi Chikama: Optical transmission apparatus, optical transmission system, and optical terminal station. Fujitsu, Staas & Halsey, February 26, 2002: US06351323 (42 worldwide citation)

In an OADM system, an OADM device includes an AOTF. The AOTF can select an optional wavelength by changing the frequency of an RF signal to be applied. An optical signal having a specified wavelength can be dropped from a wavelength-multiplexed optical signal input from an input terminal, or a wavel ...


2
Kazue Okazaki, Hiroshi Onaka, Hideyuki Miyata, Yutaka Kai, Terumi Chikama: Optical cross connect unit, optical add-drop multiplexer, light source unit, and adding unit. Fujitsu, Staas & Halsey, September 4, 2001: US06285479 (33 worldwide citation)

The present invention relates to an optical cross connect unit comprising M wavelength separating sections for receiving multiplexed optical signals each having N kinds of wavelengths different from each other through M optical fibers, respectively, and for wavelength-separating each of the multiple ...


3
Yutaka Kai, Terumi Chikama: Optical transmission device for bi-directional optical communication. Fujitsu, Staas & Halsey, August 21, 2001: US06278536 (28 worldwide citation)

This invention discloses an optical transmission device used for bi-directional optical communications. The optical transmission device comprises a uni-directional optical signal processing unit for performing specified optical signal processing for optical signals transmitted in a single direction ...


4
Yuichi Akiyama, Takeshi Hoshida, Yutaka Kai, Hiroki Ooi, Kentaro Nakamura, Naoki Kuwata, Yoshinori Nishizawa, Tomoo Takahara, Masahiro Yuki: Optical transmitting apparatus, optical receiving apparatus, and optical communication system comprising them. Fujitsu, Staas & Halsey, October 19, 2010: US07817923 (19 worldwide citation)

A phase shift unit provides a prescribed phase difference (π/2, for example) between a pair of optical signals transmitted via a pair of arms constituting a data modulation unit. A low-frequency signal f0 is superimposed on one of the optical signals. A signal of which phase is shifted by π/2 from t ...


5
Yutaka Kai, Hideyuki Miyata, Hiroshi Onaka: Wavelength locker and wavelength discriminating apparatus. Fujitsu, Staas & Halsey, August 24, 2004: US06782017 (16 worldwide citation)

An object of the invention is to provide a wavelength locker which has a wider locking range than that of the wavelength locker in the prior art and which can cope with a plurality of wavelengths. The aforementioned objects are achieved by a wavelength locker, which comprises a periodic filter, a de ...


6
Hideyuki Miyata, Hiroshi Onaka, Tadao Nakazawa, Yutaka Kai, Hiroshi Miyata, Yoichi Takasu, Naoki Hashimoto: Control method and control apparatus of optical device. Fujitsu, Staas & Halsey, April 22, 2008: US07362925 (11 worldwide citation)

The present invention aims at providing a control method and a control apparatus for controlling the operation setting of an optical device with high accuracy, so as to reliably obtain characteristics according to a desired relationship to be set corresponding to a signal light, immediately after th ...


7
Hideyuki Miyata, Hiroshi Onaka, Tadao Nakazawa, Yutaka Kai, Hiroshi Miyata, Yoichi Takasu, Naoki Hashimoto: Control method and control apparatus of optical device. Fujitsu, Staas & Halsey, August 23, 2005: US06934433 (9 worldwide citation)

The present invention aims at providing a control method and a control apparatus for controlling the operation setting of an optical device with high accuracy, so as to reliably obtain characteristics according to a desired relationship to be set corresponding to a signal light, immediately after th ...


8
Yutaka Kai, Hideyuki Miyata: Wavelength-tunable stabilizer laser. Fujitsu, Staas & Halsey, August 31, 2004: US06785306 (9 worldwide citation)

A wavelength-tunable stabilized laser is provided with a light source comprising a plurality of lasers capable of oscillating at a plurality of wavelengths, a light detecting part for detecting the light intensity of laser light output from the light source via a periodic filter, and a controlling p ...


9
Hiroshi Onaka, Hideyuki Miyata, Kazue Otsuka, Yutaka Kai, Tadao Nakazawa, Terumi Chikama: Optical transmission apparatus, optical transmission system, and optical terminal station. Fujitsu, Staas & Halsey, June 24, 2003: US06583900 (8 worldwide citation)

In an OADM system, an OADM device includes an AOTF. The AOTF can select an optional wavelength by changing the frequency of an RF signal to be applied. An optical signal having a specified wavelength can be dropped from a wavelength-multiplexed optical signal input from an input terminal, or a wavel ...


10
Yutaka Kai, Hiroshi Onaka: WAVELENGTH-DIVISION MULTIPLEXING TRANSMISSION SYSTEM, A METHOD FOR DESIGNING A LOSS DIFFERENCE COMPENSATOR FOR OPTICAL DEVICES USED IN THE WAVELENGTH-DIVISION MULTIPLEXING TRANSMISSION SYSTEM, AND A METHOD FOR CONFIGURING THE WAVELENGTH-DIVISION MULTIPLEXING TRANSMISSION SYSTEM. Fujitsu, Staas & Halsey, October 8, 2002: US06462844 (6 worldwide citation)

In a wavelength-division multiplexing transmission technique, a loss difference compensator for compensating a loss difference of an optical signal at each wavelength generated in a wavelength-division-multiplexed optical signal due to a wavelength-dependent transmission loss characteristic of an op ...