Inventor · disambiguated record
Fumihiko Yokogawa
Also filed as: YOKOGAWA FUMIHIKO
52 granted patents·2 pending applications·1,122 citations·filing 1978–2004
99Inventor score
Files withPIONEER ELECTRONIC CORP45PIONEER CORP4HITACHI LTD2MATSUSHITA ELECTRIC INDUSTRIAL CO LTD1PIONEER ELECTRIC CORP1
Top patents by PatentIndex Score
54 records- 0198US5608715AMulti-layered recording disk and recording/reproducing system using the samePIONEER ELECTRONIC CORP·Filed 1995·Granted Mar 4, 1997·273 cites·26 claims
- 0291US5914920AConstant angular velocity type optical disk, double density recording method therefor, and reproducing method for such recorded optical diskPIONEER ELECTRONIC CORP·Filed 1993·Granted Jun 22, 1999·59 cites·17 claims
- 0391US4982110AClock generator circuit and a synchronizing signal detection method in a sampled format system and a phase comparator circuit suited for generation of the clockPIONEER ELECTRONIC CORP·Filed 1989·Granted Jan 1, 1991·46 cites·5 claims
- 0489US4872155AClock generator circuit and a synchronizing signal detection method in a sampled format system and a phase comparator circuit suited for generation of the clockPIONEER ELECTRONIC CORP·Filed 1988·Granted Oct 3, 1989·39 cites·3 claims
- 0584US6463210B1Video disc having an aspect ratio information and video disc player having an aspect ratio converting functionPIONEER CORP·Filed 2000·Granted Oct 8, 2002·22 cites·16 claims
- 0684US5646932AOptical disk, tracking error signal generating apparatus, and tracking control apparatusPIONEER ELECTRONIC CORP·Filed 1995·Granted Jul 8, 1997·36 cites·2 claims
- 0784US5111443AOptical recording apparatusPIONEER ELECTRONIC CORP·Filed 1991·Granted May 5, 1992·35 cites·8 claims
- 0884US4908811AMethod and apparatus for data recording and reproducing with error reductionPIONEER ELECTRONIC CORP·Filed 1988·Granted Mar 13, 1990·30 cites·5 claims
- 0983US4937809AOptical information recording apparatusPIONEER ELECTRONIC CORP·Filed 1988·Granted Jun 26, 1990·27 cites·11 claims
- 1082US5440532ADigital signal reproducing apparatus for reproducing digital signals from a recording mediumPIONEER ELECTRONIC CORP·Filed 1994·Granted Aug 8, 1995·30 cites·2 claims
- 1182US4637003AAmplitude modulated high frequency signal detection devicePIONEER ELECTRONIC CORP·Filed 1984·Granted Jan 13, 1987·23 cites·2 claims
- 1282US4540897ADigital modulation signal reading devicePIONEER ELECTRONIC CORP·Filed 1983·Granted Sep 10, 1985·25 cites·6 claims
- 1380US5917857ADigital modulation apparatus, a digital modulation method, and a recording medium thereforMATSUSHITA ELECTRIC INDUSTRIAL CO LTD·Filed 1996·Granted Jun 29, 1999·35 cites·6 claims
- 1480US5280462ADisc playing and recording apparatus having a pair of heads controlled to prevent interruptions during playPIONEER ELECTRONIC CORP·Filed 1990·Granted Jan 18, 1994·30 cites·7 claims
- 1578US4977553AMethod and apparatus for identifying the type of servo system to be used with a given discPIONEER ELECTRONIC CORP·Filed 1988·Granted Dec 11, 1990·22 cites·11 claims
- 1677US4929917APhase-locked loop circuitPIONEER ELECTRONIC CORP·Filed 1988·Granted May 29, 1990·26 cites·5 claims
- 1776US4701902AAutomatic loading disc playerPIONEER ELECTRONIC CORP·Filed 1985·Granted Oct 20, 1987·20 cites·2 claims
- 1875US5065384AClock signal generating circuit for a data storing and reproducing systemPIONEER ELECTRONIC CORP·Filed 1988·Granted Nov 12, 1991·20 cites·3 claims
- 1974US4933922AApparatus for generating a tracking error signalPIONEER ELECTRONIC CORP·Filed 1988·Granted Jun 12, 1990·19 cites·2 claims
- 2071US5987066ADigital data transmitting methodTOSHIBA KK·Filed 1996·Granted Nov 16, 1999·60 cites·14 claims
- 2169US4860271AServo circuit for generating a tracking error signal for optical disk playerPIONEER ELECTRONIC CORP·Filed 1988·Granted Aug 22, 1989·17 cites·7 claims
- 2267US5434840ANon-linear reflectance optical information recording layer irradiated by a light beam controlled with an amplitude filterPIONEER ELECTRONIC CORP·Filed 1993·Granted Jul 18, 1995·18 cites·3 claims
- 2366US5246758AOptical recording mediumPIONEER ELECTRONIC CORP·Filed 1992·Granted Sep 21, 1993·16 cites·13 claims
- 2466US4879705AAutomatic loading disc playerPIONEER ELECTRONIC CORP·Filed 1988·Granted Nov 7, 1989·15 cites·12 claims
- 2563US4829502AAutomatic loading disc playerPIONEER ELECTRONIC CORP·Filed 1987·Granted May 9, 1989·12 cites·3 claims
- 2662US4974081AClock pulse generating circuitPIONEER ELECTRONIC CORP·Filed 1990·Granted Nov 27, 1990·21 cites·5 claims
- 2760US4520282AElectronic impedance circuit including a compensation arrangement for d.c. offsetHITACHI LTD·Filed 1982·Granted May 28, 1985·10 cites·1 claims
- 2858US4787078AOptical data recording and reproducing system with control of high frequency superposed signal applied to semiconductor laserPIONEER ELECTRONIC CORP·Filed 1987·Granted Nov 22, 1988·10 cites·4 claims
- 2957US5629924AOptical disk having synchronous marks and data marks to satisfy certain criteriaPIONEER ELECTRONIC CORP·Filed 1996·Granted May 13, 1997·10 cites·5 claims
- 3057US5600626AOptical disk of sampled servo type having synchronization a marks for simple synchronization detectionPIONEER ELECTRONIC CORP·Filed 1994·Granted Feb 4, 1997·10 cites·1 claims
- 3156US5163036ADuty factor control circuit with variable output pulse width functionPIONEER ELECTRONIC CORP·Filed 1991·Granted Nov 10, 1992·10 cites·8 claims
- 3256US4866691AAC amplifying RF signal processing circuit for optical disk playerPIONEER ELECTRONIC CORP·Filed 1988·Granted Sep 12, 1989·10 cites·4 claims
- 3355US4145664AAudio signal compression and expansion systemPIONEER ELECTRONIC CORP·Filed 1978·Granted Mar 20, 1979·8 cites·3 claims
- 3454US5740152ASpindle servo circuit in an apparatus for playing an optical disk having synchronous marks and data marks satisfying certain criteriaPIONEER ELECTRONIC CORP·Filed 1997·Granted Apr 14, 1998·9 cites·2 claims
- 3551US5617406AOptical disc with heat blocking bands between tracksPIONEER ELECTRONIC CORP·Filed 1995·Granted Apr 1, 1997·9 cites·9 claims
- 3651US5089900ASpindle control device in optical disk recording/reproducing apparatusPIONEER ELECTRIC CORP·Filed 1990·Granted Feb 18, 1992·8 cites·5 claims
- 3750US7190664B2High density optical recording medium and method for reproducing thereofPIONEER CORP·Filed 2001·Granted Mar 13, 2007·1 cites·6 claims
- 3848US6968121B2Video disc having an aspect ratio information and video disc player having an aspect ratio converting functionPIONEER ELECTRONIC CORP·Filed 2002·Granted Nov 22, 2005·0 cites·16 claims
- 3948US4513242AElectronic impedance device for providing a variable impedancePIONEER ELECTRONIC CORP·Filed 1982·Granted Apr 23, 1985·7 cites·10 claims
- 4047USRE40312EDigital data transmitting methodPIONEER ELECTRONIC CORP·Filed 2004·Granted May 13, 2008·0 cites·14 claims
- 4146US5471448ATracking servo apparatus for use in an optical disk playerPIONEER ELECTRONIC CORP·Filed 1994·Granted Nov 28, 1995·6 cites·3 claims
- 4242US5434836AOptical disk, tracking error signal generating apparatus, and tracking control apparatusPIONEER ELECTRONIC CORP·Filed 1993·Granted Jul 18, 1995·4 cites·4 claims
- 4341US5430700AApparatus for playing optical recording medium with combination tracks and plural beams tracking servoPIONEER ELECTRONIC CORP·Filed 1994·Granted Jul 4, 1995·6 cites·2 claims
- 4440US5376422AOptical recording medium and apparatus for playing such a mediumPIONEER ELECTRONIC CORP·Filed 1992·Granted Dec 27, 1994·5 cites·5 claims
- 4540US5124808ASpindle control device in optical disk recording/reproducing apparatusPIONEER ELECTRONIC CORP·Filed 1990·Granted Jun 23, 1992·4 cites·6 claims
- 4640US5103441ADuty factor control circuit with variable output pulse width functionPIONEER ELECTRONIC CORP·Filed 1991·Granted Apr 7, 1992·4 cites·4 claims
- 4740US2003086360A1Optical disk, copy preventive method, and recordable optical diskPIONEER CORP·Filed 2002·Application pending·0 cites
- 4839US5583846AOptical disc and system for generating a tracking error signal for the optical discPIONEER ELECTRONIC CORP·Filed 1995·Granted Dec 10, 1996·4 cites·6 claims
- 4938US2002080713A1Optical disc having pits of desired taper anglePIONEER CORP·Filed 2001·Application pending·0 cites
- 5036US4737696AActuator drive circuitPIONEER ELECTRONIC CORP·Filed 1987·Granted Apr 12, 1988·5 cites·28 claims
Showing the top 50 of 54 patent records by PatentIndex Score.
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Identity basis: PatentsView inventor disambiguation (2025Q4-odp release). How scoring works →