Inventor · disambiguated record
Koichi Maruyama
Also filed as: MARUYAMA KOICHI
139 granted patents·4 pending applications·2,461 citations·filing 1972–2022
99Inventor score
Top patents by PatentIndex Score
143 records- 0197US6118594AObjective lens for optical pick-upASAHI OPTICAL CO LTD·Filed 1999·Granted Sep 12, 2000·147 cites·11 claims
- 0296US8570668B2Imaging optical system and imaging apparatusTAKAKUBO YUTAKA·Filed 2011·Granted Oct 29, 2013·127 cites·10 claims
- 0395US6191889B1Objective lens for optical pick-upASAHI OPTICAL CO LTD·Filed 1999·Granted Feb 20, 2001·110 cites·7 claims
- 0494US10513968B2Refrigerant control valve apparatusAISIN SEIKI·Filed 2015·Granted Dec 24, 2019·10 cites·4 claims
- 0594US6807019B2Objective lens having diffractive structure for optical pick-upPENTAX CORP·Filed 2002·Granted Oct 19, 2004·43 cites·7 claims
- 0693US10072556B2Refrigerant control valve apparatusAISIN SEIKI·Filed 2015·Granted Sep 11, 2018·7 cites·3 claims
- 0793US6594222B2Objective lens for optical pick-upPENTAX CORP·Filed 2000·Granted Jul 15, 2003·40 cites·15 claims
- 0892US5629799AChromatic aberration correcting element and its applicationASAHI OPTICAL CO LTD·Filed 1993·Granted May 13, 1997·79 cites·4 claims
- 0991US11441690B2Valve device and assembly method of valve deviceAISIN CORP·Filed 2021·Granted Sep 13, 2022·3 cites·6 claims
- 1091US6344935B1Optical system of optical pick-upASAHI OPTICAL CO LTD·Filed 2000·Granted Feb 5, 2002·36 cites·11 claims
- 1190US7035193B2Objective lens for optical discPENTAX CORP·Filed 2005·Granted Apr 25, 2006·11 cites·18 claims
- 1289US10514103B2Refrigerant control valve apparatusAISIN SEIKI·Filed 2015·Granted Dec 24, 2019·6 cites·13 claims
- 1389US6480344B1Objective lens for optical pick-upASAHI OPTICAL CO LTD·Filed 2000·Granted Nov 12, 2002·28 cites·17 claims
- 1488US6791932B1Optical system of optical pick-upPENTAX CORP·Filed 2000·Granted Sep 14, 2004·26 cites·8 claims
- 1588US4142131AColor picture tubeHITACHI LTD·Filed 1977·Granted Feb 27, 1979·29 cites·15 claims
- 1687US5796520AChromatic aberration correcting element and its applicationASAHI OPTICAL CO LTD·Filed 1996·Granted Aug 18, 1998·32 cites·12 claims
- 1786US5838496ADiffractive multi-focal objective lensASAHI OPTICAL CO LTD·Filed 1996·Granted Nov 17, 1998·75 cites·8 claims
- 1885US6785203B2Optical lens for optical disc drive with aberration suppression for recording/reproducing for a plurality of optical disc typesPENTAX CORP·Filed 2001·Granted Aug 31, 2004·20 cites·14 claims
- 1984US5321550AOptical system of optical information recording/reproducing apparatusASAHI OPTICAL CO LTD·Filed 1993·Granted Jun 14, 1994·23 cites·16 claims
- 2084US5237457AApparatus for adjusting an optical axis including a laser beam source and a beam shaping prismASAHI OPTICAL CO LTD·Filed 1991·Granted Aug 17, 1993·27 cites·9 claims
- 2183US6760295B1Optical pick-upPENTAX CORP·Filed 1999·Granted Jul 6, 2004·40 cites·22 claims
- 2282US7738345B2Optical disc drive and objective lens for the sameHOYA CORP·Filed 2006·Granted Jun 15, 2010·5 cites·18 claims
- 2382US6624941B2Diffraction optical elementPENTAX CORP·Filed 2002·Granted Sep 23, 2003·24 cites·10 claims
- 2482US6545807B2Refractive-diffractive hybrid lensPENTAX CORP·Filed 2000·Granted Apr 8, 2003·16 cites·2 claims
- 2582US5297114AMagneto-optic recording/reproduction apparatus for minimizing variation in focusing error signals caused by variation in optical source wavelengthASAHI OPTICAL CO LTD·Filed 1991·Granted Mar 22, 1994·35 cites·7 claims
- 2681US6982838B2Objective lens for optical pick-upPENTAX CORP·Filed 2004·Granted Jan 3, 2006·15 cites·13 claims
- 2781US6819504B2High NA objective lens for optical pick-upPENTAX CORP·Filed 2002·Granted Nov 16, 2004·15 cites·11 claims
- 2881US6473387B1Optical disc apparatusASAHI OPTICAL CO LTD·Filed 2000·Granted Oct 29, 2002·19 cites·10 claims
- 2981US5969862AChromatic aberration correcting element and its applicationASAHI OPTICAL CO LTD·Filed 1997·Granted Oct 19, 1999·35 cites·4 claims
- 3081US5883744AChromatic aberration correcting element and its applicationASAHI OPTICAL CO LTD·Filed 1997·Granted Mar 16, 1999·21 cites·14 claims
- 3180US7839752B2Optical disc drive and objective lens for the sameHOYA CORP·Filed 2006·Granted Nov 23, 2010·4 cites·42 claims
- 3280US7430159B2Optical pick-up and objective lens for use with different types of optical discsHOYA CORP·Filed 2005·Granted Sep 30, 2008·4 cites·18 claims
- 3380US7054254B2High NA objective lens for optical pick-upPENTAX CORP·Filed 2002·Granted May 30, 2006·15 cites·10 claims
- 3480US6791934B2Objective lens optical system, optical head and optical information reproduction apparatusHITACHI LTD·Filed 2002·Granted Sep 14, 2004·13 cites·7 claims
- 3580US5278401AOptical disc apparatus having five light receiving areas for detecting focus error and tracking errorASAHI OPTICAL CO LTD·Filed 1992·Granted Jan 11, 1994·29 cites·11 claims
- 3679US8011352B2Gas introducing structure of intake pathAISIN SEIKI·Filed 2009·Granted Sep 6, 2011·10 cites·19 claims
- 3779US6667943B1Optical disc apparatusPENTAX CORP·Filed 2000·Granted Dec 23, 2003·15 cites·2 claims
- 3879US5461513AImage stabilizing apparatusASAHI OPTICAL CO LTD·Filed 1993·Granted Oct 24, 1995·40 cites·16 claims
- 3978US7742370B2Objective lens and optical information read/write deviceHOYA CORP·Filed 2006·Granted Jun 22, 2010·3 cites·47 claims
- 4078US6785215B2Astigmatic objective lens for optical headPENTAX CORP·Filed 2001·Granted Aug 31, 2004·15 cites·9 claims
- 4178US5991102ABeam protecting deviceASAHI OPTICAL CO LTD·Filed 1995·Granted Nov 23, 1999·46 cites·15 claims
- 4278US5642223ATilting lens systemASAHI OPTICAL CO LTD·Filed 1995·Granted Jun 24, 1997·15 cites·19 claims
- 4378US5039211AZoom lens capable of image blur compensationASAHI OPTICAL CO LTD·Filed 1989·Granted Aug 13, 1991·36 cites·27 claims
- 4478US4229675AColor picture tube with internal funnel shaped magnetic shieldHITACHI LTD·Filed 1978·Granted Oct 21, 1980·19 cites·10 claims
- 4577US6624942B2Objective lens for optical pick-upPENTAX CORP·Filed 2002·Granted Sep 23, 2003·18 cites·10 claims
- 4677US6487161B2Objective lens and optical head for optical disc driveHITACHI LTD·Filed 2001·Granted Nov 26, 2002·12 cites·9 claims
- 4777US4948233ABeam shaping optical systemASAHI OPTICAL CO LTD·Filed 1988·Granted Aug 14, 1990·37 cites·9 claims
- 4876US6822800B2Objective lens for optical pickupPENTAX CORP·Filed 2003·Granted Nov 23, 2004·11 cites·18 claims
- 4976US5657168AOptical system of optical information recording/ reproducing apparatusASAHI OPTICAL CO LTD·Filed 1995·Granted Aug 12, 1997·19 cites·11 claims
- 5076US5477386AOptical system for optical disc apparatus including anamorphic prismsASAHI OPTICAL CO LTD·Filed 1992·Granted Dec 19, 1995·24 cites·21 claims
Showing the top 50 of 143 patent records by PatentIndex Score.
Join the waitlist — get patent alerts
Get an alert when Koichi Maruyama files or is granted a new patent.
We store only your email — no account needed. See our privacy policy.
Identity basis: PatentsView inventor disambiguation (2025Q4-odp release). How scoring works →