Inventor · disambiguated record
Seiji Kumagai
Also filed as: KUMAGAI SEIJI
22 granted patents·6 pending applications·273 citations·filing 1985–2024
95Inventor score
Files withSONY CORP12SUMITOMO ELECTRIC INDUSTRIES8DOWA ECO SYSTEM CO LTD2MITSUBISHI SHINDO KK2DEXERIALS CORP1
Top patents by PatentIndex Score
28 records- 0192US8089716B2Magnetic tape, magnetic tape apparatus, servo pattern recording apparatus, magnetic tape producing method, and magnetic tape recording methodTAKAYAMA JUN·Filed 2008·Granted Jan 3, 2012·25 cites·21 claims
- 0291US12068788B2Receiver circuit for optical communicationSUMITOMO ELECTRIC INDUSTRIES·Filed 2022·Granted Aug 20, 2024·2 cites·13 claims
- 0391US11486760B2Receiving circuit and optical receiving circuitSUMITOMO ELECTRIC INDUSTRIES·Filed 2021·Granted Nov 1, 2022·2 cites·8 claims
- 0488US11405111B2Receiving circuit and optical receiverSUMITOMO ELECTRIC INDUSTRIES·Filed 2020·Granted Aug 2, 2022·2 cites·12 claims
- 0576US10436964B2Inorganic polarizing plate, method of manufacturing the same, and optical instrumentDEXERIALS CORP·Filed 2018·Granted Oct 8, 2019·2 cites·16 claims
- 0672US6213650B1Method of making optical moduleSUMITOMO ELECTRIC INDUSTRIES·Filed 1999·Granted Apr 10, 2001·38 cites·5 claims
- 0772US5667752ACopper alloy sheet for connectors and connectors formed of sameMITSUBISHI SHINDO KK·Filed 1996·Granted Sep 16, 1997·23 cites·4 claims
- 0869US6519123B1Method to manufacture magnetic tunneling elements using inductively coupled plasmaSONY CORP·Filed 1999·Granted Feb 11, 2003·30 cites·12 claims
- 0965US6365948B1Magnetic tunneling junction deviceSONY CORP·Filed 1997·Granted Apr 2, 2002·22 cites·6 claims
- 1065US4974716ADevice for feeding can barrelsHOKKAI CAN·Filed 1989·Granted Dec 4, 1990·24 cites·3 claims
- 1164US2025357566A1Recycled positive-electrode material, method for producing same, method for using recycled positive-electrode material, recycled positive electrode, and lithium ion secondary batteryDOWA ECO SYSTEM CO LTD·Filed 2023·Application pending·0 cites
- 1262US2024332273A1Optical module and flexible substrateSUMITOMO ELECTRIC INDUSTRIES·Filed 2024·Application pending·0 cites
- 1361US6535364B1Magnetic resistance element having four magnetization states and a magnetic device using the sameSONY CORP·Filed 2000·Granted Mar 18, 2003·10 cites·31 claims
- 1461US5515222AMagnetic head core arrangement having medium facing surface sides formed of single-crystal ferriteSONY CORP·Filed 1994·Granted May 7, 1996·13 cites·4 claims
- 1561US2025113429A1Optical module and flexible printed circuit boardSUMITOMO ELECTRIC INDUSTRIES·Filed 2024·Application pending·0 cites
- 1658US2024195370A1Receiver circuit and optical receiver circuitSUMITOMO ELECTRIC INDUSTRIES·Filed 2023·Application pending·0 cites
- 1757US5737154ARotary magnetic head apparatus with circuitry for driving head and circuitry for transmitting output signals in noncontact fashion disposed on rotary drumsSONY CORP·Filed 1996·Granted Apr 7, 1998·13 cites·10 claims
- 1857US2024387892A1Recycled cathode material precursor, recycled cathode material, method for manufacturing them, and recycled lithium ion secondary batteryDOWA ECO SYSTEM CO LTD·Filed 2022·Application pending·0 cites
- 1952US6219213B1Magnetic head with magnetic tunnel element in which induced magnetic field changes relative angle of magnetization which affects tunnel currentSONY CORP·Filed 1998·Granted Apr 17, 2001·10 cites·6 claims
- 2051US6312840B1Magnetic tunneling element and manufacturing method thereforSONY CORP·Filed 1999·Granted Nov 6, 2001·15 cites·19 claims
- 2149US4668471ACopper alloy lead material for leads of a semiconductor deviceMITSUBISHI SHINDO KK·Filed 1985·Granted May 26, 1987·18 cites·17 claims
- 2248US11394352B2Transimpedance amplifier circuitSUMITOMO ELECTRIC INDUSTRIES·Filed 2020·Granted Jul 19, 2022·0 cites·8 claims
- 2344US6103406AMagnetic tunnel deviceSONY CORP·Filed 1998·Granted Aug 15, 2000·11 cites·4 claims
- 2443US2007230090A1Capacitor and electronic circuitEUDYNA DEVICES INC·Filed 2007·Application pending·0 cites
- 2536US5475551AMagnetic headSONY CORP·Filed 1994·Granted Dec 12, 1995·3 cites·8 claims
- 2635US6452892B1Magnetic tunnel device, method of manufacture thereof, and magnetic headSONY CORP·Filed 1999·Granted Sep 17, 2002·6 cites·19 claims
- 2734US5867887AManufacturing method for magnetic headSONY CORP·Filed 1996·Granted Feb 9, 1999·2 cites·9 claims
- 2832US5936815AMagnetic headSONY CORP·Filed 1997·Granted Aug 10, 1999·2 cites·9 claims
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Identity basis: PatentsView inventor disambiguation (2025Q4-odp release). How scoring works →