Inventor · disambiguated record
Hajime Koyanagi
Also filed as: KOYANAGI HAJIME
19 granted patents·4 pending applications·492 citations·filing 1993–2021
95Inventor score
Top patents by PatentIndex Score
23 records- 0197US5436448ASurface observing apparatus and methodHITACHI LTD·Filed 1993·Granted Jul 25, 1995·134 cites·24 claims
- 0286US5457670AOptical disk information recording apparatus and reproducing apparatus having a plurality of read or write beamsPIONEER ELECTRONIC CORP·Filed 1993·Granted Oct 10, 1995·35 cites·6 claims
- 0383US6967908B2Optical pickup device with focus error detecting optical element and method for focus error detectionPIONEER CORP·Filed 2001·Granted Nov 22, 2005·17 cites·20 claims
- 0482US5633844AOptical pickup device with three beam tracking servo control using oval beamsPIONEER ELECTRONIC CORP·Filed 1994·Granted May 27, 1997·28 cites·6 claims
- 0580US7612334B2Standard reference component for calibration, fabrication method for the same, and scanning electron microscope using the sameHITACHI HIGH TECH CORP·Filed 2007·Granted Nov 3, 2009·5 cites·15 claims
- 0679US6370107B1Recording medium and recording deviceHITACHI LTD·Filed 1999·Granted Apr 9, 2002·50 cites·13 claims
- 0776US5467642AScanning probe microscope and method of control error correctionHITACHI LTD·Filed 1993·Granted Nov 21, 1995·46 cites·26 claims
- 0875US7750296B2Scanning electron microscope and calibration of image distortionHITACHI HIGH TECH CORP·Filed 2007·Granted Jul 6, 2010·3 cites·9 claims
- 0974US5627815APrecision machining method precision machining apparatus and data storage apparatus using the sameHITACHI LTD·Filed 1995·Granted May 6, 1997·22 cites·12 claims
- 1073US5808977ATracking method and recording means therebyHITACHI LTD·Filed 1996·Granted Sep 15, 1998·45 cites·14 claims
- 1171US6442125B1Optical pickupPIONEER ELECTRONIC CORP·Filed 1999·Granted Aug 27, 2002·23 cites·14 claims
- 1267US5471064APrecision machining method, precision machining apparatus and data storage apparatus using the sameHITACHI LTD·Filed 1993·Granted Nov 28, 1995·24 cites·19 claims
- 1366US6370092B1Optical pickup and optical disk drive for use with a high-density optical diskPIONEER ELECTRONIC CORP·Filed 1999·Granted Apr 9, 2002·18 cites·25 claims
- 1461US5889752AOptical pickup apparatus with a crosstalk balance detecting circuitPIONEER ELECTRONIC CORP·Filed 1997·Granted Mar 30, 1999·15 cites·35 claims
- 1555US5572493AOptical disk information recording apparatus and reproducing apparatus having a plurality of read or write beamsPIONEER ELECTRONIC CORP·Filed 1995·Granted Nov 5, 1996·10 cites·6 claims
- 1655US2025060580A1Optical device and sensor devicePIONEER CORP·Filed 2021·Application pending·0 cites
- 1749US12038535B2Detection device, method of detecting distance to object, program, and storage mediumPIONEER CORP·Filed 2018·Granted Jul 16, 2024·0 cites·9 claims
- 1847US7683313B2Charged particle beam measurement equipment, size correction and standard sample for correctionHITACHI HIGH TECH CORP·Filed 2008·Granted Mar 23, 2010·0 cites·5 claims
- 1947US6246652B1Device using sensor for small rotation angleHITACHI LTD·Filed 1998·Granted Jun 12, 2001·13 cites·9 claims
- 2042US2001040864A1Recording medium and recording deviceHITACHI LTD·Filed 2001·Application pending·0 cites
- 2141US5784345AOptical pickup device for eliminating unwanted dataPIONEER ELECTRONIC CORP·Filed 1997·Granted Jul 21, 1998·4 cites·7 claims
- 2239US2019265357A1Sensor device, sensing method, program, and storage mediumPIONEER CORP·Filed 2017·Application pending·0 cites
- 2338US2002034108A1Pickup deviceFiled 2001·Application pending·0 cites
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Identity basis: PatentsView inventor disambiguation (2025Q4-odp release). How scoring works →