Inventor · disambiguated record
Keiji Sakai
Also filed as: SAKAI KEIJI
48 granted patents·7 pending applications·1,021 citations·filing 1989–2020
98Inventor score
Files withSHARP KK24HITACHI LTD5KOBELCO CONSTR MACH CO LTD3HITACHI HIGH TECH CORP2KAWASAKI STEEL CO2
Top patents by PatentIndex Score
55 records- 0197US7098055B2Apparatus and method for testing defectsHITACHI HIGH TECH CORP·Filed 2005·Granted Aug 29, 2006·36 cites·7 claims
- 0296US7940383B2Method of detecting defects on an objectHITACHI LTD·Filed 2009·Granted May 10, 2011·42 cites·20 claims
- 0396US7639350B2Apparatus and method for testing defectsHITACHI LTD·Filed 2007·Granted Dec 29, 2009·25 cites·20 claims
- 0496US6411377B1Optical apparatus for defect and particle size inspectionHITACHI LTD·Filed 1999·Granted Jun 25, 2002·174 cites·29 claims
- 0593US7443496B2Apparatus and method for testing defectsHITACHI LTD·Filed 2007·Granted Oct 28, 2008·16 cites·15 claims
- 0692US7037735B2Apparatus and method for testing defectsHITACHI HIGH TECH CORP·Filed 2002·Granted May 2, 2006·43 cites·18 claims
- 0791US7692779B2Apparatus and method for testing defectsHITACHI LTD·Filed 2005·Granted Apr 6, 2010·12 cites·20 claims
- 0891US6328166B1Bill arrangerLAUREL BANK MACHINE CO·Filed 2000·Granted Dec 11, 2001·33 cites·12 claims
- 0989US6540090B1Bill arrangerLAUREL BANK MACHINES COMPANY L·Filed 2000·Granted Apr 1, 2003·99 cites·15 claims
- 1088US6868055B2Optical pickupSHARP KK·Filed 2001·Granted Mar 15, 2005·26 cites·37 claims
- 1188US5502457AFiber optic face plate for a seamless modular displaySHARP KK·Filed 1994·Granted Mar 26, 1996·77 cites·7 claims
- 1288US5465315ADisplay apparatus having a plurality of display devicesSHARP KK·Filed 1992·Granted Nov 7, 1995·76 cites·15 claims
- 1387US5013494AProcess for preparing blazed hologramsSHARP KK·Filed 1989·Granted May 7, 1991·56 cites·11 claims
- 1484US7106682B2Optical pickupSHARP KK·Filed 2005·Granted Sep 12, 2006·6 cites·8 claims
- 1582US10184872B2Viscosity/elasticity measurement device and measurement methodSAKAI KEIJI·Filed 2012·Granted Jan 22, 2019·7 cites·19 claims
- 1682US5719834AObjective lens driving apparatus and method including visco-elastic support for a magnetic circuit which allows translation of the magnetic circuit without pivoting or rotating there ofSHARP KK·Filed 1996·Granted Feb 17, 1998·36 cites·24 claims
- 1781US8365582B2Device for measuring viscosity/elasticity and method for measuring viscosity/elasticityUNIV TOKYO·Filed 2009·Granted Feb 5, 2013·7 cites·17 claims
- 1880US6406558B1Method for manufacturing magnetic steel sheet having superior workability and magnetic propertiesKAWASAKI STEEL CO·Filed 2000·Granted Jun 18, 2002·14 cites·4 claims
- 1978US5279924AManufacturing method of optical diffraction grating element with serrated gratings having uniformly etched groovesSHARP KK·Filed 1992·Granted Jan 18, 1994·47 cites·12 claims
- 2076US7486403B2Droplet shape measuring method and apparatusCANON KK·Filed 2007·Granted Feb 3, 2009·9 cites·5 claims
- 2174US6339562B1Optical pickup deviceSHARP KK·Filed 1998·Granted Jan 15, 2002·27 cites·7 claims
- 2273US8727592B2Light source module and electronic apparatus provided with sameISHIZAKA TAKUYA·Filed 2010·Granted May 20, 2014·5 cites·10 claims
- 2372US9372141B2Viscosity measuring apparatusYASUDA MASANORI·Filed 2012·Granted Jun 21, 2016·2 cites·17 claims
- 2469US7483360B2Optical pickup device using polarizing hologram element and hologram laser thereforSHARP KK·Filed 2004·Granted Jan 27, 2009·8 cites·16 claims
- 2569US5602808AObjective lens driving apparatusSHARP KK·Filed 1994·Granted Feb 11, 1997·16 cites·1 claims
- 2669US5408264AThree-dimensional image display apparatus for optically synthesizing images formed on different surfaces on a display screenSHARP KK·Filed 1992·Granted Apr 18, 1995·27 cites·6 claims
- 2768US6428632B1Non-oriented electromagnetic steel sheet having reduced magnetic anisotropy in high frequency region and excellent press workabilityKAWASAKI STEEL CO·Filed 2000·Granted Aug 6, 2002·8 cites·5 claims
- 2867US7649825B2Splitting element, light emitter, and optical pickup apparatusSHARP KK·Filed 2004·Granted Jan 19, 2010·7 cites·8 claims
- 2965US7184384B2Optical pickupSHARP KK·Filed 2003·Granted Feb 27, 2007·6 cites·33 claims
- 3063US7625673B2Electrode material for electrochemical element and method for production thereof, and electrochemical elementHITACHI MAXELL·Filed 2001·Granted Dec 1, 2009·5 cites·10 claims
- 3159US7315502B2Light integration unit, optical pickup device using the unit, and optical disk deviceSHARP KK·Filed 2002·Granted Jan 1, 2008·4 cites·14 claims
- 3258USD438556SBank note sorterLAUREL BANK MACHINE CO·Filed 1999·Granted Mar 6, 2001·10 cites·1 claims
- 3358US5509094AMode splitter and a magneto-optical disk pick-up device having the mode splitterSHARP KK·Filed 1994·Granted Apr 16, 1996·17 cites·9 claims
- 3457US7019280B2Apparatus for detecting the tilt of a light reflector relative to the optical axis of input lightSHARP KK·Filed 2002·Granted Mar 28, 2006·8 cites·27 claims
- 3556US8757348B2Paper money input and output deviceYOSHIKAWA EIICHI·Filed 2006·Granted Jun 24, 2014·2 cites·13 claims
- 3655US8599447B2Illuminating apparatus, image reading apparatus, and image forming apparatusSUTO YASUHIRO·Filed 2009·Granted Dec 3, 2013·0 cites·12 claims
- 3751US12195310B2CraneKOBELCO CONSTR MACH CO LTD·Filed 2020·Granted Jan 14, 2025·0 cites·10 claims
- 3851US6388977B1Hologram laser unit and optical pickup device including the sameSHARP KK·Filed 1999·Granted May 14, 2002·9 cites·7 claims
- 3950US10168267B2Rotational speed detection device, viscosity measurement device using the device, rotational speed detection method, and rotating object used in the methodKYOTO ELECTRONICS MFG·Filed 2014·Granted Jan 1, 2019·0 cites·14 claims
- 4048US8051321B2Cluster system and node switching methodFUJITSU LIMITD·Filed 2009·Granted Nov 1, 2011·0 cites·5 claims
- 4147US9518908B2Fluid mechanical property measurement method and measurement deviceTHE FOUND FOR THE PROMOTION OF IND SCIENCE·Filed 2013·Granted Dec 13, 2016·0 cites·10 claims
- 4247US7136409B2Semiconductor laser device and optical pickup deviceSHARP KK·Filed 2004·Granted Nov 14, 2006·2 cites·13 claims
- 4345US11981542B2Hoisting implement, hoisting implement system, and method for using hoisting implement systemKOBELCO CONSTR MACH CO LTD·Filed 2019·Granted May 14, 2024·0 cites·8 claims
- 4445US7882942B2Coin bar storageLAUREL PREC MACHINES CO LTD·Filed 2008·Granted Feb 8, 2011·0 cites·3 claims
- 4545US5576149AMethod for producing a tapered waveguideSHARP KK·Filed 1994·Granted Nov 19, 1996·11 cites·12 claims
- 4644US10053159B2Cabin support deckKOBELCO CONSTR MACH CO LTD·Filed 2017·Granted Aug 21, 2018·0 cites·10 claims
- 4744US2008018969A1Optical Integrated Unit Including Hologram Element and Optical Pickup DeviceSHARP KK·Filed 2005·Application pending·0 cites
- 4844US2007159954A1Laser oscillation element and optical pickup deviceSHARP KK·Filed 2005·Application pending·0 cites
- 4944US2006018212A1Focus error detecting device and optical pickup apparatus provided with the sameSHARP KK·Filed 2005·Application pending·0 cites
- 5043US8189434B2Optical pickup unit and optical pickup device having same and information writing/reading device having sameMIYAZAKI OSAMU·Filed 2005·Granted May 29, 2012·0 cites·8 claims
Showing the top 50 of 55 patent records by PatentIndex Score.
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Identity basis: PatentsView inventor disambiguation (2025Q4-odp release). How scoring works →