Inventor · disambiguated record
Kei Yasuna
Also filed as: YASUNA KEI
30 granted patents·1 pending application·174 citations·filing 2000–2024
96Inventor score
Files withWESTERN DIGITAL TECH INC10HITACHI GLOBAL STORAGE TECH6NONAKA KEIICHIRO6HITACHI LTD3YASUNA KEI3
Top patents by PatentIndex Score
31 records- 0193US11587587B1Method to measure thermal protrusion by sensing spacing change due to pre-lasingWESTERN DIGITAL TECH INC·Filed 2022·Granted Feb 21, 2023·4 cites·20 claims
- 0292US6597532B1Information recording disk apparatusHITACHI LTD·Filed 2000·Granted Jul 22, 2003·44 cites·8 claims
- 0391US11587586B1Determining laser induced thermal protrusion and laser threshold in heat-assisted magnetic recording (HAMR) data storageWESTERN DIGITAL TECH INC·Filed 2022·Granted Feb 21, 2023·3 cites·20 claims
- 0489US11830524B1Data storage device with split burst servo patternWESTERN DIGITAL TECH INC·Filed 2022·Granted Nov 28, 2023·3 cites·20 claims
- 0587US12046265B1Data storage device with enhanced management of laser pre-bias and logic block addressing in heat-assisted magnetic recordingWESTERN DIGITAL TECH INC·Filed 2023·Granted Jul 23, 2024·1 cites·20 claims
- 0687US6970320B2Servo pattern recording methodHITACHI GLOBAL STORAGE TECH·Filed 2003·Granted Nov 29, 2005·23 cites·3 claims
- 0785US7646561B2Method of writing pattern in disk, method of following track on disk, and apparatus for writing pattern in diskHITACHI GLOBAL STORAGE TECH·Filed 2007·Granted Jan 12, 2010·7 cites·16 claims
- 0885US6906884B2Magnetic disk apparatus and its servo signal recording methodHITACHI LTD·Filed 2002·Granted Jun 14, 2005·20 cites·9 claims
- 0984US8619379B2Patterned media with an alternating series of concentric servo zones and overlap zonesNONAKA KEIICHIRO·Filed 2011·Granted Dec 31, 2013·8 cites·35 claims
- 1083US12100431B1Data storage device with symmetric split burst servo patternWESTERN DIGITAL TECH INC·Filed 2023·Granted Sep 24, 2024·1 cites·20 claims
- 1180US8630051B2Patterned media with an alternating series of concentric servo zones and overlap zonesNONAKA KEIICHIRO·Filed 2011·Granted Jan 14, 2014·6 cites·35 claims
- 1278US7085084B2Magnetic disk apparatus and servo pattern recording method thereforHITACHI GLOBAL STORAGE TECH·Filed 2003·Granted Aug 1, 2006·13 cites·2 claims
- 1378US6888696B2Magnetic disk apparatus and servo signal recording methodHITACHI GLOBAL STORAGE TECH·Filed 2002·Granted May 3, 2005·13 cites·2 claims
- 1475US12347468B2Energy-assisted magnetic recording data storage device with opportunistic boosted laser pre-biasingWESTERN DIGITAL TECH INC·Filed 2023·Granted Jul 1, 2025·0 cites·20 claims
- 1573US8023220B2Method for writing servo data to a disk and disk drive configured to write servo data utilizing the methodHITACHI GLOBAL STORAGE TECH NL·Filed 2009·Granted Sep 20, 2011·2 cites·18 claims
- 1672US8531794B2Patterned media with an alternating series of concentric servo zones and overlap zonesNONAKA KEIICHIRO·Filed 2011·Granted Sep 10, 2013·3 cites·24 claims
- 1770US10923146B1Data storage device employing triangle-like dither to spread track squeezeWESTERN DIGITAL TECH INC·Filed 2020·Granted Feb 16, 2021·1 cites·19 claims
- 1870US8670207B2Servo pattern compatible with planarization constraints of patterned media and use of a single master templateNONAKA KEIICHIRO·Filed 2011·Granted Mar 11, 2014·2 cites·20 claims
- 1970US6999261B2Magnetic disk device and servo write methodHITACHI GLOBAL STORAGE TECH·Filed 2002·Granted Feb 14, 2006·8 cites·13 claims
- 2068US8625219B2Patterned media with an alternating series of concentric servo zones and overlap zonesNONAKA KEIICHIRO·Filed 2011·Granted Jan 7, 2014·2 cites·35 claims
- 2164US12512122B2Data storage device with servo burst signal correction for mitigating effects of servo pattern distortionWESTERN DIGITAL TECH INC·Filed 2024·Granted Dec 30, 2025·0 cites·20 claims
- 2264US12431161B1Data storage device with track pitch determination for mitigating effects of servo pattern distortionWESTERN DIGITAL TECH INC·Filed 2024·Granted Sep 30, 2025·0 cites·21 claims
- 2364US8526132B2Servo patterning compatible with planarization of patterned magnetic disksALBRECHT THOMAS R·Filed 2010·Granted Sep 3, 2013·1 cites·20 claims
- 2464US6636385B2Magnetic disc apparatus having actuator for head positioning mechanismHITACHI LTD·Filed 2001·Granted Oct 21, 2003·5 cites·6 claims
- 2563US12277957B1Data storage device with embedded mode hop predictor patternsWESTERN DIGITAL TECH INC·Filed 2023·Granted Apr 15, 2025·0 cites·20 claims
- 2658US8085489B2Method for writing servo patterns and disk drive including a controller for writing servo patterns according to the methodHATTORI RYOHHEITA·Filed 2009·Granted Dec 27, 2011·1 cites·16 claims
- 2755US8873183B2Disk drive and method of writing servo write tracks to a diskYASUNA KEI·Filed 2010·Granted Oct 28, 2014·1 cites·14 claims
- 2851US7116509B2Magnetic disk apparatus and servo signal recording methodHITACHI GLOBAL STORAGE TECH·Filed 2003·Granted Oct 3, 2006·2 cites·13 claims
- 2947US8743496B2Servo pattern compatible with planarization constraints of patterned media and use of a single master templateNONAKA KEIICHIRO·Filed 2011·Granted Jun 3, 2014·0 cites·31 claims
- 3046US2009009904A1Method for forming servo pattern and magnetic disk driveYASUNA KEI·Filed 2008·Application pending·0 cites
- 3145US8559126B2Method and apparatus for positioning a magnetic-recording headYASUNA KEI·Filed 2009·Granted Oct 15, 2013·0 cites·8 claims
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Identity basis: PatentsView inventor disambiguation (2025Q4-odp release). How scoring works →