Inventor · disambiguated record
Keiji Koga
Also filed as: KOGA KEIJI
41 granted patents·4 pending applications·636 citations·filing 1986–2009
98Inventor score
Top patents by PatentIndex Score
45 records- 0195US5419938AMagnetic recording medium comprising two magnetic layers of hexagonal ferrite magnetic particles and binder wherein the easy axes of the particle is specifiedTDK CORP·Filed 1993·Granted May 30, 1995·111 cites·6 claims
- 0290US5565284ALithium secondary cellTDK CORP·Filed 1993·Granted Oct 15, 1996·89 cites·13 claims
- 0384US5589297ALithium secondary cellTDK CORP·Filed 1994·Granted Dec 31, 1996·71 cites·10 claims
- 0483US7825658B2Magnetic device and frequency detectorTDK CORP·Filed 2008·Granted Nov 2, 2010·11 cites·11 claims
- 0583US4772522AMagnetic recording mediumTDK CORP·Filed 1987·Granted Sep 20, 1988·28 cites·13 claims
- 0682US7991377B2Mixer and frequency converting apparatusTDK CORP·Filed 2009·Granted Aug 2, 2011·8 cites·7 claims
- 0780US4794042AMagnetic recording mediumTDK CORP·Filed 1986·Granted Dec 27, 1988·35 cites·3 claims
- 0879US7942192B2Vehicle air conditionerJAPAN CLIMATE SYSTEMS CORP·Filed 2006·Granted May 17, 2011·6 cites·9 claims
- 0978US5160761AMethod for making a magnetic diskTDK CORP·Filed 1992·Granted Nov 3, 1992·26 cites·3 claims
- 1077US6930911B2Magnetic memory device, method for writing on the same and method for reading from the sameTDK CORP·Filed 2003·Granted Aug 16, 2005·24 cites·26 claims
- 1177US5530609AMagnetic recording/reproducing method using a thin film magneticTDK CORP·Filed 1994·Granted Jun 25, 1996·26 cites·9 claims
- 1276US7808229B2Magnetic device and frequency analyzerTDK CORP·Filed 2007·Granted Oct 5, 2010·8 cites·7 claims
- 1375US5340698AOptical diskTDK CORP·Filed 1992·Granted Aug 23, 1994·22 cites·7 claims
- 1474US7886814B2Vehicle air conditionerJAPAN CLIMATE SYSTEMS CORP·Filed 2006·Granted Feb 15, 2011·4 cites·10 claims
- 1567US7209380B2Magnetic memory device and method of reading the sameTDK CORP·Filed 2004·Granted Apr 24, 2007·15 cites·16 claims
- 1665US7100675B2Air conditioner for vehicleJAPAN CLIMATE SYSTEMS CORP·Filed 2002·Granted Sep 5, 2006·11 cites·11 claims
- 1765US6996001B2Magnetic memory device, write current drive circuit, and write current drive methodTDK CORP·Filed 2003·Granted Feb 7, 2006·13 cites·39 claims
- 1863US5140486AMagnetic recording and reproductionTDK CORP·Filed 1990·Granted Aug 18, 1992·14 cites·5 claims
- 1962US7227771B2Magnetoresistive effect element and magnetic memory deviceTDK CORP·Filed 2004·Granted Jun 5, 2007·8 cites·2 claims
- 2061US7295460B2Magnetic memory cell, magnetic memory device, and method of manufacturing magnetic memory deviceTDK CORP·Filed 2004·Granted Nov 13, 2007·7 cites·50 claims
- 2161US4780366AMagnetic recording medium for image recordingTDK CORP·Filed 1986·Granted Oct 25, 1988·11 cites·1 claims
- 2260US7683446B2Magnetic memory using spin injection flux reversalTDK CORP·Filed 2006·Granted Mar 23, 2010·1 cites·5 claims
- 2360US7277320B2Magnetic memory device, sense amplifier circuit and method of reading from magnetic memory deviceTDK CORP·Filed 2004·Granted Oct 2, 2007·7 cites·14 claims
- 2458US7973375B2Spin transistor and method of manufacturing sameTDK CORP·Filed 2008·Granted Jul 5, 2011·1 cites·9 claims
- 2556US7471550B2Magnetic memoryTDK CORP·Filed 2007·Granted Dec 30, 2008·3 cites·5 claims
- 2655US4741977AMagnetic sheetTDK CORP·Filed 1986·Granted May 3, 1988·9 cites·5 claims
- 2753US7016221B2Magnetoresistive effect element, magnetic memory device and method of fabricating the sameTDK CORP·Filed 2003·Granted Mar 21, 2006·7 cites·31 claims
- 2852US7697323B2Magnetic storage deviceTDK CORP·Filed 2007·Granted Apr 13, 2010·2 cites·11 claims
- 2952US7649766B2Magnetic storage deviceTDK CORP·Filed 2007·Granted Jan 19, 2010·2 cites·7 claims
- 3051US7535757B2Magnetic memoryTDK CORP·Filed 2007·Granted May 19, 2009·2 cites·10 claims
- 3151US5219708AOptical diskTDK CORP·Filed 1991·Granted Jun 15, 1993·13 cites·6 claims
- 3251US5182693AMagnetic diskTDK CORP·Filed 1992·Granted Jan 26, 1993·8 cites·3 claims
- 3350US7796419B2Magnetic memoryTDK CORP·Filed 2006·Granted Sep 14, 2010·2 cites·16 claims
- 3447US7342822B2Magnetic memory device, write current driver circuit and write current driving methodTDK CORP·Filed 2004·Granted Mar 11, 2008·5 cites·21 claims
- 3546US7613033B2Magnetic storage deviceTDK CORP·Filed 2007·Granted Nov 3, 2009·2 cites·20 claims
- 3646US2008037820A1Sound Generating ApparatusKOGA KEIJI·Filed 2005·Application pending·0 cites
- 3745US7230843B2Magnetic memory device and writing method of the sameTDK CORP·Filed 2004·Granted Jun 12, 2007·4 cites·21 claims
- 3843US6493182B1Magnetic headTDK CORP·Filed 1998·Granted Dec 10, 2002·6 cites·38 claims
- 3943US2006203538A1Magnetoresistive effect element and magnetic memoryTDK CORP·Filed 2006·Application pending·0 cites
- 4043US2006279980A1Magnetic storage cell and magnetic memory deviceTDK CORP·Filed 2004·Application pending·0 cites
- 4141US5393584AMagnetic discTDK CORP·Filed 1993·Granted Feb 28, 1995·4 cites·6 claims
- 4236US7522450B2Magnetic storage cell, magnetic memory device and magnetic memory device manufacturing methodTDK CORP·Filed 2004·Granted Apr 21, 2009·0 cites·40 claims
- 4335US7470964B2Magnetic memory and manufacturing method thereofTDK CORP·Filed 2005·Granted Dec 30, 2008·0 cites·4 claims
- 4434US2006062075A1Magnetic memoryTDK CORP·Filed 2005·Application pending·0 cites
- 4531US4834213ANoise silencer for use in joint gap in highwayYAMAMOTO IKURO·Filed 1988·Granted May 30, 1989·10 cites·3 claims
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Identity basis: PatentsView inventor disambiguation (2025Q4-odp release). How scoring works →