Inventor · disambiguated record
Youichi Akasaka
Also filed as: AKASAKA YOUICHI
62 granted patents·13 pending applications·938 citations·filing 1995–2024
98Inventor score
Files withFUJITSU LTD33FURUKAWA ELECTRIC CO LTD19SPRINT COMMUNICATIONS CO11AKASAKA YOUICHI9FUJITSU NETWORK COMMUNICATIONS1
Top patents by PatentIndex Score
75 records- 0199US6292288B1Raman amplifier, optical repeater, and raman amplification methodFURUKAWA ELECTRIC CO LTD·Filed 2000·Granted Sep 18, 2001·201 cites·54 claims
- 0295US7692852B2Raman amplifier, optical repeater, and Raman amplification methodFURUKAWA ELECTRIC CO LTD·Filed 2007·Granted Apr 6, 2010·16 cites·20 claims
- 0394US11438086B2Optical amplification in an optical networkFUJITSU LTD·Filed 2020·Granted Sep 6, 2022·4 cites·15 claims
- 0494US8107815B2System and method for communicating wireless data utilizing a passive optical networkAKASAKA YOUICHI·Filed 2008·Granted Jan 31, 2012·35 cites·25 claims
- 0593US11121797B1Optical system for compensating for signal lossFUJITSU LTD·Filed 2020·Granted Sep 14, 2021·3 cites·14 claims
- 0693US9837788B2Optical phase-sensitive amplifier with raman amplifier intermediate stageFUJITSU LTD·Filed 2015·Granted Dec 5, 2017·11 cites·20 claims
- 0793US6775057B2Raman amplifier, optical repeater, and raman amplification methodFURUKAWA ELECTRIC CO LTD·Filed 2002·Granted Aug 10, 2004·24 cites·22 claims
- 0893US5995694AWavelength division multiplex communication link for optical transmissionFURUKAWA ELECTRIC CO LTD·Filed 1997·Granted Nov 30, 1999·131 cites·3 claims
- 0992US6501593B2Raman amplifier, optical repeater, and raman amplification methodFURUKAWA ELECTRIC CO LTD·Filed 2001·Granted Dec 31, 2002·23 cites·51 claims
- 1091US11032004B1Optical system for compensating for signal lossFUJITSU LTD·Filed 2020·Granted Jun 8, 2021·3 cites·18 claims
- 1190US5673354ADispersion compensating optical fiberFURUKAWA ELECTRIC CO LTD·Filed 1996·Granted Sep 30, 1997·106 cites·4 claims
- 1290US5568583ADispersion compensating optical fiber for wavelength multiplex transmission and method using sameFURUKAWA ELECTRIC CO LTD·Filed 1995·Granted Oct 22, 1996·98 cites·10 claims
- 1389US9281654B2Raman amplifier, optical repeater, and Raman amplification methodFURUKAWA ELECTRIC CO LTD·Filed 2013·Granted Mar 8, 2016·4 cites·26 claims
- 1487US8705167B2System and method for compensating for polarization dependent lossAKASAKA YOUICHI·Filed 2010·Granted Apr 22, 2014·8 cites·19 claims
- 1587US6636344B2Raman amplifier, optical repeater, and raman amplification methodFURUKAWA ELECTRIC CO LTD·Filed 2001·Granted Oct 21, 2003·14 cites·41 claims
- 1686US2025055248A1Stimulated brillouin scattering suppressed highly non-linear optical fiberFUJITSU LTD·Filed 2024·Application pending·0 cites
- 1785US8798454B2Method and system for automatic lane negotiation in an optical networkAKASAKA YOUICHI·Filed 2010·Granted Aug 5, 2014·8 cites·20 claims
- 1885US8543006B2System and method for reducing polarization dependent lossVASSILIEVA OLGA I·Filed 2010·Granted Sep 24, 2013·7 cites·18 claims
- 1984US9997887B1Optical phase-sensitive amplifier with fiber bragg grating phase shifterFUJITSU LTD·Filed 2017·Granted Jun 12, 2018·3 cites·18 claims
- 2084US7548368B2Raman amplifier, optical repeater, and raman amplification methodFURUKAWA ELECTRIC CO LTD·Filed 2004·Granted Jun 16, 2009·10 cites·6 claims
- 2182US10498102B2Optical phase-sensitive amplifier with signal noise removalFUJITSU LTD·Filed 2017·Granted Dec 3, 2019·3 cites·15 claims
- 2282US6654162B2Raman amplifier, optical repeater, and Raman amplification methodFURUKAWA ELECTRIC CO LTD·Filed 2001·Granted Nov 25, 2003·10 cites·122 claims
- 2380US8437074B2Raman amplifier, optical repeater, and Raman amplification methodAKASAKA YOUICHI·Filed 2011·Granted May 7, 2013·2 cites·32 claims
- 2479US10050738B1Low noise colorless, directionless, contentionless reconfigurable optical add/drop multiplexerFUJITSU LTD·Filed 2017·Granted Aug 14, 2018·3 cites·12 claims
- 2579US8873950B2Method and system of automatic regeneration of optical signalsAKASAKA YOUICHI·Filed 2011·Granted Oct 28, 2014·4 cites·22 claims
- 2677US12170434B2Stimulated Brillouin scattering suppressed highly non-linear optical fiberFUJITSU LTD·Filed 2022·Granted Dec 17, 2024·0 cites·6 claims
- 2775US5802235ADispersion compensating fiber and its manufacturing methodFURUKAWA ELECTRIC CO LTD·Filed 1997·Granted Sep 1, 1998·41 cites·3 claims
- 2873US5887104ADispersion compensating optical fiberFURUKAWA ELECTRIC CO LTD·Filed 1997·Granted Mar 23, 1999·40 cites·9 claims
- 2972US6646787B2Raman amplifier, optical repeater, and Raman amplification methodFURUKAWA ELECTRIC CO LTD·Filed 2002·Granted Nov 11, 2003·5 cites·6 claims
- 3070US9515727B2In-band optical signal-to-noise ratio monitorFUJITSU LTD·Filed 2015·Granted Dec 6, 2016·2 cites·3 claims
- 3170US8909062B2Optical signal regeneration and amplification of M-PSK and M-QAM modulation formats using reconfigurable wavelength selective processors and phase-sensitive amplifiersYANG JENG-YUAN·Filed 2012·Granted Dec 9, 2014·4 cites·24 claims
- 3270US2025316946A1Erbium doped fiber optical amplifier with adaptive filterFUJITSU LTD·Filed 2024·Application pending·0 cites
- 3369US5854871ADispension shift optical fiber and wavelength division multiplex transmission system using the sameFURUKAWA ELECTRIC CO LTD·Filed 1997·Granted Dec 29, 1998·38 cites·9 claims
- 3469US2025266656A1Hybrid optical amplifierFUJITSU LTD·Filed 2024·Application pending·0 cites
- 3569US2025273919A1Multi-band erbium doped fiber optical amplifierFUJITSU LTD·Filed 2024·Application pending·0 cites
- 3668US12074690B2Optical signal power gainFUJITSU LTD·Filed 2022·Granted Aug 27, 2024·0 cites·20 claims
- 3768US8909063B2Optical QPSK signal regeneration and amplificationFUJITSU NETWORK COMMUNICATIONS·Filed 2012·Granted Dec 9, 2014·2 cites·20 claims
- 3868US5848215AStimulated brillouin scattering suppressed optical fiberFURUKAWA ELECTRIC CO LTD·Filed 1997·Granted Dec 8, 1998·33 cites·8 claims
- 3968US2025149845A1Forward raman pumping with respect to dispersion shifted fibersFUJITSU LTD·Filed 2023·Application pending·0 cites
- 4067US6876488B1Discrete amplification of an optical signalSPRINT COMMUNICATIONS CO·Filed 2003·Granted Apr 5, 2005·9 cites·21 claims
- 4165US2024258758A1Optical signal amplificationFUJITSU LTD·Filed 2023·Application pending·0 cites
- 4264US12463396B2Raman optical amplifier with fabry-perot pump laserFUJITSU LTD·Filed 2021·Granted Nov 4, 2025·0 cites·20 claims
- 4361US9515733B2Mitigation of spectral offset in an optical filterFUJITSU LTD·Filed 2015·Granted Dec 6, 2016·1 cites·21 claims
- 4461US2010067099A1Raman amplifier, optical repeater, and raman amplification methodFURUKAWA ELECTRIC CO LTD·Filed 2009·Application pending·0 cites
- 4559US10256911B2Harmonic generation and phase sensitive amplification using a bragg reflection waveguideFUJITSU LTD·Filed 2018·Granted Apr 9, 2019·0 cites·14 claims
- 4659US7565083B1Wavelength shifting in an optical network route to mitigate distortion in different types of fiberSPRINT COMMUNICATIONS CO·Filed 2004·Granted Jul 21, 2009·5 cites·20 claims
- 4759US7352973B1Adding wavelengths to an optical communication networkSPRINT COMMUNICATIONS CO·Filed 2004·Granted Apr 1, 2008·4 cites·15 claims
- 4858US11563300B2Suppressing signal noise on an optical fiberFUJITSU LTD·Filed 2019·Granted Jan 24, 2023·0 cites·15 claims
- 4957US7623798B1Polarization mode dispersion mitigation of multiple optical communication channelsSPRINT COMMUNICATIONS CO·Filed 2005·Granted Nov 24, 2009·1 cites·17 claims
- 5056US11506916B2Dual polarization optical pumpingFUJITSU LTD·Filed 2021·Granted Nov 22, 2022·0 cites·16 claims
Showing the top 50 of 75 patent records by PatentIndex Score.
Join the waitlist — get patent alerts
Get an alert when Youichi Akasaka files or is granted a new patent.
We store only your email — no account needed. See our privacy policy.
Identity basis: PatentsView inventor disambiguation (2025Q4-odp release). How scoring works →