Inventor
ONAKA HIROSHI
JP85 patents
Patents
50 patentsUS5894362AApr 13, 1999
Optical communication system which determines the spectrum of a wavelength division multiplexed signal and performs various processes in accordance with the determined spectrum
FUJITSU LTD179 citations99
US6351323B1Feb 26, 2002
Optical transmission apparatus, optical transmission system, and optical terminal station
FUJITSU LTD87 citations98
US5841557ANov 24, 1998
Method and apparatus for scrambling the polarization of signal lights forming a wavelength division multiplexed signal light
FUJITSU LTD106 citations98
US5737118AApr 7, 1998
Optical amplifying apparatus
FUJITSU LTD117 citations98
US5696859ADec 9, 1997
Optical-filter array, optical transmitter and optical transmission system
FUJITSU LTD108 citations98
US5696614ADec 9, 1997
Optical wavelength multiplex transmission method and optical dispersion compensation method
FUJITSU LTD85 citations97
US6654561B1Nov 25, 2003
Method and apparatus for measuring optical signal-to-noise ratio, and pre-emphasis method and optical communication system each utilizing the method
FUJITSU LTD60 citations96
US6417945B2Jul 9, 2002
Optical wavelength multiplex transmission method and optical dispersion compensation method
FUJITSU LTD30 citations96
US6288834B1Sep 11, 2001
Optical amplifier for amplifying light in a long wavelength band
FUJITSU LTD49 citations96
US6285479B1Sep 4, 2001
Optical cross connect unit, optical add-drop multiplexer, light source unit, and adding unit
FUJITSU LTD66 citations96
US6243176B1Jun 5, 2001
Optical wavelength multiplex transmission method and optical dispersion compensation method
FUJITSU LTD34 citations96
US6067187AMay 23, 2000
Optical amplifier and optical communication system employing the same
FUJITSU LTD60 citations96
US5973821AOct 26, 1999
Variable optical attenuator which applies a magnetic field to a faraday element to rotate the polarization of light signal
FUJITSU LTD50 citations96
US5867300AFeb 2, 1999
Variable optical attenuator which applies a magnetic field to a faraday element to rotate the polarization of a light signal
FUJITSU LTD79 citations96
US5646399AJul 8, 1997
Tunable optical filter having beam splitter and movable film filter
FUJITSU LTD60 citations96
US5636046AJun 3, 1997
Optical dispersion compensation method using transmissible band determined from synergetic effect of self phase modulation and group velocity dispersion
FUJITSU LTD48 citations96
US5612807AMar 18, 1997
Optical dispersion compensation method for shifting a zero dispersion wavelength of an optical fiber to compensate for dispersion in an optical system
FUJITSU LTD31 citations96
US5602666AFeb 11, 1997
Optical dispersion compensation method for shifting a zero dispersion wavelength of an optical fiber to compensate for dispersion in an optical system
FUJITSU LTD56 citations96
US4965858AOct 23, 1990
Polarization diversity optical receiver for coherent optical communication
FUJITSU LTD57 citations96
US7848659B2Dec 7, 2010
Optical transmitting apparatus and optical communication system
FUJITSU LTD22 citations93
US7006771B1Feb 28, 2006
Optical communication apparatus and optical add/drop apparatus
FUJITSU LTD14 citations93
US6941078B1Sep 6, 2005
Method and system for communicating a clock signal over an optical link
FUJITSU LTD41 citations93
US6782017B1Aug 24, 2004
Wavelength locker and wavelength discriminating apparatus
FUJITSU LTD51 citations93
US6462844B1Oct 8, 2002
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 LTD22 citations93
US6366376B1Apr 2, 2002
Optical transmitting device using wavelength division multiplexing to transmit signal lights having frequencies arranged to eliminate effects of four-wave mixing (FWM)
FUJITSU LTD29 citations93
US6333806B1Dec 25, 2001
Variable optical attenuator which applies a magnetic field to a Faraday element to rotate the polarization of a light signal
FUJITSU LTD27 citations93
US6018411AJan 25, 2000
Optical device utilizing magneto-optical effect
FUJITSU LTD28 citations93
US5596448AJan 21, 1997
Dispersion compensator and optical amplifier
FUJITSU LTD45 citations93
US5469288ANov 21, 1995
Optical filter, method of controlling transmission wavelength thereof, and optical receiver using the method
FUJITSU LTD37 citations93
US7362925B2Apr 22, 2008
Control method and control apparatus of optical device
FUJITSU LTD18 citations92
US6934433B2Aug 23, 2005
Control method and control apparatus of optical device
FUJITSU LTD17 citations92
US6847662B2Jan 25, 2005
Wavelength-selectable laser capable of high-speed frequency control
FUJITSU LTD38 citations92
US6583900B2Jun 24, 2003
Optical transmission apparatus, optical transmission system, and optical terminal station
FUJITSU LTD27 citations92
US6538782B1Mar 25, 2003
Light branching/inserting apparatus and light branching apparatus using wavelength selection filter
FUJITSU LTD33 citations92
US6266180B1Jul 24, 2001
Optical fiber amplifier using optical fiber having a portion which suppresses nonlinear optical phenomena
FUJITSU LTD37 citations92
US6151158ANov 21, 2000
Method and device for optical amplification and system having the device
FUJITSU LTD39 citations92
US5886804AMar 23, 1999
Optical transmission system employing single mode optical transmission fiber
FUJITSU LTD32 citations92
US5050176ASep 17, 1991
Direct modulation phase-shift-keying system and method
FUJITSU LTD35 citations92
US7822204B2Oct 26, 2010
Encryption method, cryptogram decoding method, encryptor, cryptogram decoder, transmission/reception system, and communication system
FUJITSU LTD18 citations84
US7631378B2Dec 15, 2009
Optical waveform shaper
FUJITSU LTD8 citations84
US7606504B2Oct 20, 2009
Optical receiver and optical receiving method corresponding to differential M-phase shift keying system
FUJITSU LTD15 citations84
US7483639B2Jan 27, 2009
Method and system for transmitting information in an optical communication system using distributed amplification
FUJITSU LTD9 citations84
US7471790B2Dec 30, 2008
Encryption method, cryptogram decoding method, encryptor, cryptogram decoder, and communication system
FUJITSU LTD15 citations84
US7127139B2Oct 24, 2006
Optical multiplexing method and optical multiplexer, and optical amplifier using same
FUJITSU LTD12 citations84
US7088922B2Aug 8, 2006
Wavelength division multiplexing optical communication system
FUJITSU LTD15 citations84
US7035543B1Apr 25, 2006
Method and system for demultiplexing non-intensity modulated wavelength division multiplexed (WDM) signals
FUJITSU LTD18 citations84
US7860408B2Dec 28, 2010
Interferometer for demodulating differential M-phase shift keying signal
FUJITSU LTD9 citations83
US7292787B1Nov 6, 2007
Selected-wavelength tuning filter and optical add/drop multiplexer
FUJITSU LTD12 citations83
US6384943B2May 7, 2002
Optical wavelength multiplex transmission method and optical dispersion compensation method
FUJITSU LTD13 citations82
US6275314B1Aug 14, 2001
Optical wavelength multiplex transmission method and optical dispersion compensation method
FUJITSU LTD13 citations82
Showing the top 50 of 85 patents by PatentIndex Score.