Inventor · disambiguated record
Atsushi Kikugawa
Also filed as: KIKUGAWA ATSUSHI
53 granted patents·5 pending applications·621 citations·filing 1992–2015
98Inventor score
Files withHITACHI LTD23HITACHI GLOBAL STORAGE TECH9KIKUGAWA ATSUSHI8HITACHI CONSUMER ELECTRONICS7HITACHI METALS LTD3
Top patents by PatentIndex Score
58 records- 0197US5436448ASurface observing apparatus and methodHITACHI LTD·Filed 1993·Granted Jul 25, 1995·134 cites·24 claims
- 0295US7483478B2Information read device and read signal processing circuitHITACHI LTD·Filed 2005·Granted Jan 27, 2009·20 cites·15 claims
- 0394US6686070B1Perpendicular magnetic recording media, magnetic recording apparatusHITACHI LTD·Filed 2000·Granted Feb 3, 2004·95 cites·8 claims
- 0493US7852722B2Optical disk apparatus and playback signal processing methodHITACHI LTD·Filed 2006·Granted Dec 14, 2010·15 cites·5 claims
- 0592US7446685B1Read signal processing circuit, read signal processing method, and optical disc driveHITACHI LTD·Filed 2007·Granted Nov 4, 2008·14 cites·16 claims
- 0692US5416331ASurface atom fabrication method and apparatusHITACHI LTD·Filed 1992·Granted May 16, 1995·69 cites·36 claims
- 0790US7289284B2Stray field detector, magnetic disk drive, and method of head escapingHITACHI GLOBAL STORAGE TECH·Filed 2005·Granted Oct 30, 2007·11 cites·23 claims
- 0887US7026810B2Method for testing or recording servo signal on perpendicular magnetic recording mediaHITACHI LTD·Filed 2005·Granted Apr 11, 2006·6 cites·6 claims
- 0985US7616726B2Optical disk apparatus and PLL circuitHITACHI LTD·Filed 2005·Granted Nov 10, 2009·6 cites·9 claims
- 1082US9322082B2Method for recovering rare earth elementHOSHI HIROYUKI·Filed 2012·Granted Apr 26, 2016·3 cites·7 claims
- 1181US7153596B2Perpendicular magnetic recording medium, manufacturing process of the same, and magnetic storage apparatus using the sameHITACHI GLOBAL STORAGE TECH·Filed 2003·Granted Dec 26, 2006·14 cites·10 claims
- 1281US6759148B2Perpendicular magnetic recording media and magnetic storage apparatus using the sameHITACHI LTD·Filed 2001·Granted Jul 6, 2004·26 cites·1 claims
- 1380US6376089B1Process for producing rare earth metal-based permanent magnet having corrosion-resistant filmSUMITOMO SPEC METALS·Filed 2000·Granted Apr 23, 2002·19 cites·14 claims
- 1478US7791993B2Optical disc drive provided with envelope defect detection functionHITACHI LTD·Filed 2007·Granted Sep 7, 2010·3 cites·10 claims
- 1578US6723457B2Perpendicular magnetic recording media, manufacturing process of the same, and magnetic storage apparatus using the sameHITACHI LTD·Filed 2002·Granted Apr 20, 2004·32 cites·9 claims
- 1677US7217467B2Perpendicular magnetic recording medium and magnetic recording/reproducing apparatusHITACHI GLOBAL STORAGE TECH·Filed 2003·Granted May 15, 2007·11 cites·16 claims
- 1777US6894488B2Method for testing or recording servo signal on perpendicular magnetic recording mediaHITACHI LTD·Filed 2002·Granted May 17, 2005·9 cites·8 claims
- 1876US5467642AScanning probe microscope and method of control error correctionHITACHI LTD·Filed 1993·Granted Nov 21, 1995·46 cites·26 claims
- 1974US8379497B2Optical disk apparatusHITACHI CONSUMER ELECTRONICS·Filed 2009·Granted Feb 19, 2013·2 cites·18 claims
- 2074US7969838B2Optical disk apparatusHITACHI LTD·Filed 2007·Granted Jun 28, 2011·2 cites·1 claims
- 2174US5689494ASurface atom fabrication method and apparatusHITACHI LTD·Filed 1995·Granted Nov 18, 1997·22 cites·20 claims
- 2272US10233516B2Method for recovering heavy rare earth elementHITACHI METALS LTD·Filed 2014·Granted Mar 19, 2019·1 cites·8 claims
- 2369US7889607B2Optical disk device and integrated circuit used thereinHITACHI LTD·Filed 2006·Granted Feb 15, 2011·1 cites·5 claims
- 2469US7147941B2Perpendicular magnetic recording media, magnetic recording apparatusHITACHI GLOBAL STORAGE TECH·Filed 2003·Granted Dec 12, 2006·9 cites·5 claims
- 2569US7041393B2Perpendicular magnetic recording media, manufacturing process of the same, and magnetic storage apparatus using the sameHITACHI GLOBAL STORAGE TECH·Filed 2003·Granted May 9, 2006·7 cites·39 claims
- 2667US6884513B2Rare earth metal-based permanent magnet having corrosion-resistant film and method for producing the sameNEOMAX CO LTD·Filed 2001·Granted Apr 26, 2005·8 cites·5 claims
- 2766US8163106B2R-Fe-B based sintered magnet having on the surface thereof vapor deposited film of aluminum or alloy thereof, and method for producing the sameKIKUGAWA ATSUSHI·Filed 2008·Granted Apr 24, 2012·4 cites·6 claims
- 2866US6808824B2Perpendicular magnetic recording mediaHITACHI LTD·Filed 2002·Granted Oct 26, 2004·9 cites·8 claims
- 2964US7945002B2Information read device and read signal processing circuitHITACHI LTD·Filed 2009·Granted May 17, 2011·0 cites·2 claims
- 3062US9657367B2Method for producing R-Fe-B based permanent magnet alloy recycled material having removed carbonFURUSAWA KATSUYOSHI·Filed 2012·Granted May 23, 2017·1 cites·6 claims
- 3161US8045431B2Signal conversion module and optical disc apparatus using the sameHITACHI CONSUMER ELECTRONICS·Filed 2009·Granted Oct 25, 2011·0 cites·7 claims
- 3259US8243573B2High-speed optical disk driveKIKUGAWA ATSUSHI·Filed 2009·Granted Aug 14, 2012·0 cites·6 claims
- 3356US8089845B2Offset compensator and optical disc drive using the sameKIKUGAWA ATSUSHI·Filed 2008·Granted Jan 3, 2012·0 cites·8 claims
- 3455US8804476B2Optical information recording medium, recording and reproduction method, and recording and reproduction deviceHITACHI CONSUMER ELECTRONICS·Filed 2013·Granted Aug 12, 2014·0 cites·13 claims
- 3553US2009086602A1Optical information reproducing method, optical information reproducing apparatus and optical information recording mediumHITACHI LTD·Filed 2008·Application pending·0 cites
- 3652US6878217B2Rare earth metal-based permanent magnet having corrosion-resistant film and method for producing the sameNEOMAX CO LTD·Filed 2002·Granted Apr 12, 2005·3 cites·5 claims
- 3752US2009103418A1Optical disk medium, information recording method, and optical disk driveHITACHI LTD·Filed 2008·Application pending·0 cites
- 3851US8958278B2Optical information reproduction apparatus using homodyne phase diversity detection with improved SNRHITACHI CONSUMER ELECTRONICS·Filed 2013·Granted Feb 17, 2015·0 cites·13 claims
- 3951US8705328B2Read signal evaluation method, information recording and reading method, and information recording and reading apparatusKIKUGAWA ATSUSHI·Filed 2011·Granted Apr 22, 2014·0 cites·13 claims
- 4051US7399540B2Perpendicular magnetic recording media, magnetic recording apparatusHITACHI GLOBAL STORAGE TECH·Filed 2006·Granted Jul 15, 2008·2 cites·5 claims
- 4151US7138195B2Perpendicular magnetic recording media and magnetic storageHITACHI LTD·Filed 2004·Granted Nov 21, 2006·1 cites·4 claims
- 4251US6858330B2Perpendicular magnetic recording media and magnetic storage apparatus using the sameHITACHI LTD·Filed 2001·Granted Feb 22, 2005·9 cites·13 claims
- 4350US9275794B2Corrosion-resistant magnet and method for producing the sameKIKUGAWA ATSUSHI·Filed 2009·Granted Mar 1, 2016·0 cites·1 claims
- 4450US8588048B2Optical information recording medium, optical information recording and reproducing device, and recording methodHITACHI CONSUMER ELECTRONICS·Filed 2012·Granted Nov 19, 2013·0 cites·6 claims
- 4550US7852729B2Optical disc apparatus with adjustable constraint length PRMLHITACHI LTD·Filed 2005·Granted Dec 14, 2010·0 cites·6 claims
- 4649US10081040B2Method for recovering rare earth elementHITACHI METALS LTD·Filed 2013·Granted Sep 25, 2018·0 cites·5 claims
- 4749US7153546B2Perpendicular magnetic recording media, manufacturing process of the same, and magnetic storage apparatus using the sameHITACHI GLOBAL STORAGE TECH·Filed 2004·Granted Dec 26, 2006·6 cites·4 claims
- 4848US7428115B2Magnetic hard disk drive with countermeasure against spike noiseHITACHI GLOBAL STORAGE TECH·Filed 2005·Granted Sep 23, 2008·0 cites·18 claims
- 4946US9175376B2Method for producing surface-modified rare earth metal-based sintered magnet and surface-modified rare earth metal-based sintered magnetFUJIHARA MAHORO·Filed 2008·Granted Nov 3, 2015·1 cites·3 claims
- 5045US9435009B2Method and system for separating rare earth elementsHITACHI METALS LTD·Filed 2013·Granted Sep 6, 2016·0 cites·33 claims
Showing the top 50 of 58 patent records by PatentIndex Score.
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Identity basis: PatentsView inventor disambiguation (2025Q4-odp release). How scoring works →