Inventor

Kenji Ohta

Inventor

Kitakatsuragi-gun, JP

Overview

1983–2020

Patent span

Physics

Primary field (CPC G)

Patents· 249 as inventor

Public. Assignee & technology derived from the patent record. Each patent links to its LexDana page.

G11Bprimary

G11BInformation storage based on relative movement between record carrier and transducer44%

Y10STechnical subjects covered by former uspc cross-reference art collections [xracs] and digests15%

Y10TTechnical subjects covered by former us classification8%

F02DControlling combustion engines3%

G03GElectrography2%

G03FPhotomechanical production of textured or patterned surfaces, e.g. for printing, for processing of semiconductor devices2%

H04BTransmission2%

C23CCoating metallic material2%

B41JTypewriters1%

B82YSpecific uses or applications of nanostructures1%

PatentTitleYear

10,532,906Image processing apparatus2020 10,093,509Image processing apparatus2018 9,342,007'Polyimide seamless belt for image forming apparatus'2016 9,192,024'Dimming console'2015 8,820,731'Image processing apparatus'2014 8,433,832'Control equipment with communication apparatus'2013 8,244,129'Monitoring apparatus and method for polarization scrambler and optical transmission apparatus'2012 D0665012'Copier'2012 D0664591'Operating panel for a copier'2012 D0658710'Cash register'2012 8,041,231'Supervisory controlling method and supervisory controlling system of optical repeater'2011 7,849,236'Control equipment with communication apparatus'2010 7,676,160'Supervisory controlling method and supervisory controlling system of optical repeater'2010 7,580,329'Optical recording medium recorded with information in depth direction, and method and apparatus of reproduction therefrom'2009 7,450,844'WDM optical transmission equipment with redundant configuration, and wavelength control method of light output in standby system'2008 D0570400'Cash register'2008 D0564499'Input/output terminal for computer'2008 7,284,424'Thermal air flow rate measuring apparatus and its flowmeter and internal combustion engine and thermal air flow rate measuring method using it'2007 7,283,893'Group robot system, and sensing robot and base station used therefor'2007 D0537864'Cash register'2007 7,113,460'Optical disk having pits of different depths formed therein, optical disk reproducing apparatus for reproducing the optical disk, and method of tracking the optical disk'2006 7,082,351'Group robot system, and sensing robot and base station used therefor'2006 7,079,313'Optical amplifying apparatus which routes pumping light to a raman amplification medium and a rare-earth-doped optical amplification medium'2006 7,050,383'Optical recording medium recorded with information in depth direction, and method and apparatus of reproduction therefrom'2006 7,027,385'Optical disk, disk substrate, and drive'2006 D0507592'Cash register'2005 D0507526'Battery charger for an input/output terminal of a computer'2005 6,876,603'Information write/read head including an optical slit having a light emitting section whose width is shorter than a light beam diffraction limit'2005 D0501207'Input/output terminal for a computer'2005 6,819,648'Optical sample and method of writing and reading information on the same'2004 6,804,822'Magnetic recording medium and magnetic recording apparatus using same'2004 6,687,216'Cartridge in which disk is stored'2004 6,665,235'Magneto-optical recording medium and recording and reproducing method and optical head designed for the magneto-optical recording medium'2003 6,661,745'Optical reproducing and recording method, recording medium, and optical device'2003 6,648,822'Communication apparatus and communication method for outputting an estimate of a patient\'s mental state'2003 6,504,679'Erasure prevention in disc cartridge'2003 6,483,785'Magneto-optical recording method using the relation of beam diameter and an aperture of converging lens'2002 6,457,353'Apparatus of diagnosing an internal combustion engine and a method of diagnosing of an internal combustion engine'2002 6,397,673'Air flow measuring apparatus'2002 6,379,864'Method for manufacturing an optical disk'2002 6,339,231'Gate commutated turn-off thyristor module'2002 6,321,165'Air flow measurement apparatus'2001 6,261,707'Magneto-optical recording medium and recording and reproducing method and optical head designed for the magneto-optical recording medium'2001 6,230,559'Thermal type flow measuring instrument and temperature-error correcting apparatus thereof'2001 D0435854'Disc cartridge'2001 6,143,436'Magnetic recording medium and information recording-reproduction method using the same'2000 6,067,285'Optical disc'2000 6,058,100'Optical recording medium having pit rows'2000 6,055,223'Optical memory apparatus'2000 D0423040'Copier'2000 6,001,467'Magneto-optic memory medium'1999 5,989,671'Optical recording medium and manufacturing method thereof'1999 5,962,126'Method and apparatus for reproducing data from a magneto-optical recording medium having a readout layer, transfer layer and recording layer'1999 5,946,290'Tamper-proof lid lock in disc cartridge'1999 5,932,364'Magneto-optical recording medium, method of recording and reproducing information in and from said magneto-optical recording medium and method of producing said mageto-optical recording medium'1999 5,926,454'Disc cartridge with slide shutter having catch pieces'1999 5,922,177'Magneto-optical recording medium and producing method thereof'1999 5,907,525'Magneto-optical disk, optical pickup, and magneto-optical disk drive'1999 5,903,541'Disc cartridge lid structure'1999 5,863,649'Magneto-optical recording medium'1999 5,847,416'Phototrigger thyristor'1998 5,828,649'Magneto-optical memory element'1998 5,824,426'Magneto-optical recording medium'1998 5,820,795'Manufacturing method of magneto-optical master disk'1998 5,809,005'Method for manufacturing a magneto-optical memory element'1998 5,804,841'Optical trigger thyristor and fabrication method'1998 5,777,953'Arrangement of magneto-optical recording medium which capable of reproducing an individual bit'1998 5,764,601'Method of manufacturing a magneto-optical recording medium having a readout layer with varying composition and curie temperature'1998 5,757,401'Ink jet head, method of using thereof and method of manufacturing thereof'1998 5,754,523'Optical memory medium with preformed pit arrangement'1998 5,740,153'Magneto-optical disk, optical pickup, and magneto-optical disk drive'1998 5,738,765'Magneto-optic memory device'1998 5,736,090'Method of in-mold coating'1998 5,737,105'Optical repeater'1998 5,719,831'Magneto-optical recording medium cartridge which employs magnets'1998 5,714,251'Magneto-optic memory device'1998 5,707,727'Magneto-optical recording medium'1998 5,705,286'Magneto-optical recording medium'1998 5,699,088'Recording head for a magnetic printer'1997 5,691,963'Magneto-optical recording device using light-modulated technic without an initial magnetic field'1997 5,684,519'Ink jet head with buckling structure body'1997 5,683,803'Magneto-optical recording medium and method of recording and reproducing using the same'1997 5,680,376'Optical recording medium, and apparatus and method for recording and reproducing information on the same'1997 5,676,854'Optical memory having narrowed track pitch'1997 RE035629'Magneto-optical memory element'1997 5,674,583'Optical recording medium and manufacturing method thereof'1997 5,673,250'Optical recording medium having pit rows on every other boundary and reproducing method thereof'1997 5,666,141'Ink jet head and a method of manufacturing thereof'1997 5,666,345'Optical memory medium with predetermined guide tracks and prepits'1997 5,665,467'Magneto-optical recording medium'1997 5,662,988'Magneto-optical recording medium'1997 5,656,385'Magnetic recording medium and information recording-reproduction method using the same'1997 5,648,162'Magneto-optical recording medium and a method of recording and/or reproducing using the same'1997 5,645,978'Method for manufacturing optical disk'1997 5,644,466'Power feed circuit for use in a submarine cable branching unit'1997 5,643,687'Magneto-optic memory medium and a method for producing the same'1997 5,644,566'Magneto-optical recording medium'1997 5,637,394'Magneto-optical recording medium and method of reproducing magneto-optical information using thereof'1997 5,635,296'Magneto-optical recording medium whereon overwriting is permitted by light intensity modulation'1997 5,631,096'Magneto optical memory device'1997 5,627,576'Ink jet head using excited progressive waves'1997 5,615,180'Magneto-optical recording medium and magneto-optical recording apparatus capable of performing a light-modulation overwriting operation'1997 5,615,182'Magneto-optical disk and the reproducing method thereof'1997 D0378099'Copier'1997 5,600,627'Optical disk and a method for recording, reproducing, and deleting information on and from the optical disk'1997 5,595,805'Magneto-optical recording medium'1997 5,587,994'Cartridge used for a disc-shaped recording medium'1996 5,586,109'Optical memory having narrowed track pitch'1996 5,581,538'Recording/reproducing apparatus with a probe to detect data recorded in pits and projections of a recording medium'1996 5,581,397'Optical-fiber amplifier'1996 5,570,336'Information recording and reproducing apparatus having a slider formal of single crystal silicon body and cantilever'1996 5,563,852'Magneto-optical recording medium having a readout layer with varying composition and curie temperature'1996 5,554,436'Magneto-optical recording medium'1996 5,546,364'Magneto-optical memory apparatus utilizing edges or recording mark to manage data'1996 5,544,149'Optical recording medium, and apparatus and method for recording and reproducing information on the same'1996 D0372227'Scanner'1996 5,535,586'Engine ignition period controller'1996 5,529,043'Signal processor'1996 5,530,685'Magneto-optical recording apparatus having paired devices for applying external magnetic fields'1996 5,500,850'Optical disk with grooves and pits of different depths'1996 5,499,229'Track scanning for reproducing address information by crosstalk'1996 5,491,500'Ink jet head'1996 5,490,131'Optical disk'1996 5,486,395'Magneto-optical disk'1996 5,477,528'Magneto-optical disk and the reproducing method thereof'1995 5,477,524'Optical memory medium with preformed pit arrangement'1995 5,475,658'Magneto-optical recording device for improving C/N ratio'1995 5,474,049'Engine fuel injection controller'1995 5,470,694'Optical memory element and manufacturing method thereof'1995 5,459,711'Optical recording element and driving system'1995 5,457,006'Method of manufacturing photo-mask and photo-mask manufactured thereby'1995 5,453,975'Optical disc with surface coating and manufacturing method therefor'1995 5,453,884'Magneto-optical recording medium'1995 5,452,272'Magneto-optical recording and reproducing device having light interrupting forming main robe and side robe light beam portions'1995 5,438,561'Method for recording and reproducing information using an optical memory'1995 5,428,585'Magneto-optical recording medium comprising first, second and third magnetic layers and method of recording on same'1995 5,427,833'Magneto-optical recording medium and method for processing the surface'1995 5,425,349'Engine fuel injection controller'1995 5,425,008'Magneto-optical memory device whereon overwriting operation can be carried out through light intensity modulation and method for recording and erasing using it'1995 5,422,865'Light modulation method for magneto-optical recording device'1995 5,414,652'Magneto-optical memory element'1995 5,412,630'Tracking system for optical disc memory using tracking error signals from main beam and auxiliary beams'1995 5,404,862'Engine fuel injection controller'1995 5,403,683'Photo-mask'1995 5,402,408'Magneto-optical recording method of overwriting without requiring an initialization magnet'1995 5,399,461'Optical disk for use in optical memory devices'1995 5,398,011'Microrelay and a method for producing the same'1995 5,386,400'Magneto-optical head device having a lubricated member'1995 5,383,176'Optical disk'1995 5,353,278'Magneto-optical disk and method of manufacturing the same'1994 5,347,510'Method of manufacturing a master plate where its guide groove has an inclined angle'1994 5,343,448'External magnetic field device for a magnetooptical information recording and reproducing apparatus'1994 5,341,362'Optical memory device having guide tracks shaped for increasing the quality of information signals'1994 5,338,646'Optical memory device having an improved light reflection or optical memory layer'1994 5,336,531'Magneto-optical disk and manufacturing methods thereof'1994 5,334,879'Feeding system and feeding method for a submarine cable communication system'1994 5,335,220'Optical recording element and driving system'1994 5,331,625'Optical disc with antistatic coating containing tin oxide and phosphorous'1994 5,331,612'Magneto-optical recording apparatus using the magnetic field modulation method'1994 5,328,740'Magneto-optical recording medium and method for processing the surface'1994 5,328,256'Anti-skid brake control device'1994 5,325,344'Magneto-optical recording and reproducing device having integrally formed recording and reproducing magnetic heads'1994 5,317,555'Optical head device utilizing partially overlapping light spots to read information from a readout layer'1994 5,313,357'Magnetic storage device and manufacturing method thereof'1994 5,305,300'Magneto optical storage device using a multi-layer film of Pt/Co laminated sections'1994 5,305,254'Magneto-optic memory device'1994 5,303,100'Magnetic disk device with floating-type magnetic head'1994 5,293,359'Magnetic recording and reproducing apparatus having a ferrimagnetic recording medium, a magnetic head and first and second light sources'1994 5,286,583'Method of manufacturing a photomask for an optical memory'1994 5,278,810'Magneto-optical recording medium whereon recording is carried out with an overwriting function'1994 5,270,995'Method for recording and reproducing information by varying a work function of a recording medium and device for the same'1993 5,270,994'Magneto-optical recording and reading method'1993 5,260,150'Photo-mask with light shielding film buried in substrate'1993 5,233,597'Magneto-optical disk having a layer of varying thickness'1993 5,231,613'Magneto-optical recording device'1993 5,224,068'Recording method for magneto-optic memory medium'1993 5,214,636'Optical recording element having a plurality of thin film filtering layers and optical recording element having an electrically conductive layer'1993 5,202,862'Magneto-optical recording and reproducing device having integrally formed recording and reproducing magnetic heads'1993 5,202,860'Magneto-optic reproducing device using right and left circularly polarized light'1993 5,196,978'Cartridge case'1993 5,193,082'Optical/magnetic composite head having magnetic and optical heads in one integrated unit'1993 5,192,644'Optical memory device'1993 5,187,703'Magneto-optical multilayer recording disk and method of reproducing the same'1993 5,175,079'Optical memory device'1992 5,175,721'Magneto-optical recording and reading device with initilization'1992 5,170,390'Optical recording element and driving system'1992 5,160,572'Optical memory device and apparatus for manufacturing the same'1992 5,157,568'Floating type magnetic head device'1992 5,155,715'Reproducing apparatus'1992 D0328891'Memorandum input and output terminal'1992 5,128,922'Optical disk with glass substrate and method of producing same'1992 5,117,415'Optical card, a card holder and an apparatus for recording, reproducing and erasing information on and from the optical card'1992 5,112,727'Method of and photomask for manufacturing optical memory element'1992 5,107,471'Magnetic head having a rectangular configuration for use in a magneto-optical recording system'1992 5,107,486'Optical memory device with grooves and pits in selected dimensional relationship'1992 D0325571'Data input and output terminal'1992 5,095,350'Magneto-optic memory medium'1992 D0324513'Data input and output terminal'1992 5,092,420'Throttle valve position controlling apparatus and slip controlling apparatus'1992 D0324208'Data input and output terminal'1992 5,087,535'Method of manufacturing photo-mask and photo-mask manufactured thereby'1992 5,088,086'Optical recording medium and the method of recording, reading, and erasing information using it'1992 5,082,690'Process for manufacturing a magneto-optic disc'1992 5,083,301'Optical card recording and reproducing device'1992 5,081,614'Magneto-optical head utilizing central and peripheral portions of reflected light flux for different purposes'1992 5,079,113'Photo-mask'1992 5,077,714'Magneto-optical recording and reproducing device using the modulation of intensities of the magnetic field and light beam'1991 5,077,725'Optical memory device and apparatus for manufacturing the same'1991 5,068,841'Magneto-optical recording/reproducing device'1991 5,066,381'Target unit'1991 5,059,473'Optical recording medium and manufacturing method thereof'1991 5,053,611'Device for reducing mechanical vibrations when utilizing a magneto-optical card as a recording medium'1991 5,053,252'Method and apparatus for manufacturing optical memory devices'1991 5,002,813'Substrate with protective film and method of manufacturing optical memory device using the same'1991 4,985,885'Optical memory device'1991 4,982,710'Electronic throttle valve opening control method and system therefor'1991 4,956,243'Optical memory element'1990 4,946,730'Method of and photomask for manufacturing optical memory element'1990 4,944,375'Reduction gearing device for a windshield wiper motor including a unidirectional brake'1990 4,925,776'Optical memory element and manufacturing method thereof'1990 4,920,437'Disc clamping device'1990 4,917,751'Method of producing double sided optical memory disks'1990 4,911,125'Method and apparatus for controlling throttle valve in internal combustion engine'1990 4,881,216'Optical head in an optical memory device'1989 4,858,212'Recording method on magnetooptical disc with laser magnetic field'1989 4,839,251'Photo-mask for use in manufacturing an optical memory disc, a method for making the photo-mask and a method for manufacturing the optical memory disc'1989 4,818,648'Optical memory element'1989 4,792,474'Optical memory element'1988 4,787,076'Optical disc tracking system with switching of tracking error signals at boundary between track guide and track address'1988 4,786,559'Magnetooptical storage element'1988 4,778,747'Method of manufacturing optical memory element'1988 4,764,441'Photo-mask for production of substrate for optical memory element'1988 4,754,355'Optical head'1988 4,740,947'Dual surface optical memory disc'1988 4,719,137'Magneto-optic memory element'1988 4,717,628'Magnetooptical storage element'1988 4,695,514'Magneto-optical memory element'1987 4,677,601'Method of forming permanent memory locations in a magnetooptic memory medium'1987 4,658,393'Optical memory disc'1987 4,634,617'Optical memory disc'1987 4,610,912'Magneto-optic memory element'1986 4,573,149'Magneto-optical head assembly with improved detection means'1986 4,544,443'Method for manufacturing an optical memory element'1985 4,497,006'Magneto-optic recording/playback head assembly'1985 4,489,139'Magneto-optic memory medium'1984 4,467,383'Magnetooptic memory medium'1984 4,414,650'Magneto-optic memory element'1983 4,400,844'Wiper device'1983 4,390,600'Magneto-optic memory medium'1983

Career & activity timeline

Assembled from patent assignee/location history and declaration credentials.

1983–2020Patents assigned to SHARP KK (205)· patent assignee history

1983–2000Based in Yao, JP· patent location history

1988–2004Based in Nara, JP· patent location history

1990–2013Patents assigned to HITACHI LTD (10)· patent assignee history

1991–2009Based in Kitakatsuragi-gun, JP· patent location history

1992–2015Based in Osaka, JP· patent location history

1994–2012Patents assigned to FUJITSU LTD (9)· patent assignee history

1994–2012Based in Kawasaki, JP· patent location history

1999–2006Patents assigned to HITACHI MAXELL (7)· patent assignee history

2012–2016Patents assigned to OHTA KENJI (7)· patent assignee history

Inventor activity

Assignee and location history derived from the patent record.

Assignees

Assignee	Patents	Span
SHARP KK	205	1983–2020
HITACHI LTD	10	1990–2013
FUJITSU LTD	9	1994–2012
HITACHI MAXELL	7	1999–2006
OHTA KENJIself	7	2012–2016

Locations

Location	Patents	Span
Kitakatsuragi-gun, JP	90	1991–2009
Nara, JP	73	1988–2004
Yao, JP	23	1983–2000
Osaka, JP	18	1992–2015
Kawasaki, JP	9	1994–2012