Inventor
KAKU TOSHIMITSU
JP72 patents
Patents
50 patentsUS4949331AAug 14, 1990
Apparatus and record carrier for optical disc memory with correction pattern and master disc cutting apparatus
HITACHI LTD128 citations99
US6088307AJul 11, 2000
Wobble signal detecting circuit, wobble abnormality detecting circuit, information processing apparatus using these circuits and method and recording medium used in the apparatus or method
HITACHI LTD129 citations98
US5732061AMar 24, 1998
Recording method using trial write test pattern
HITACHI LTD114 citations98
US5642343AJun 24, 1997
Magnetooptic disc apparatus and recording medium
HITACHI LTD117 citations98
US6483791B1Nov 19, 2002
Laser drive integrated circuit and optical disk apparatus using the same
HITACHI LTD52 citations96
US6414932B1Jul 2, 2002
Information recording/reproducing apparatus with laser driver
HITACHI LTD48 citations96
US5974021AOct 26, 1999
Determination of optimal recording power in optical disk recording and retrieving device
HITACHI LTD56 citations96
US5848045ADec 8, 1998
Method for recording and reading an optical disk
HITACHI LTD70 citations96
US5590111ADec 31, 1996
Method of controlling recording of optical records
HITACHI LTD73 citations96
US4866687ASep 12, 1989
Optical disc access method and optical disk storage using coarse and fine actuators
HITACHI LTD100 citations96
US4866688ASep 12, 1989
Composite tracking servo system for optical disc apparatus with track offset correction
HITACHI LTD111 citations96
US4663751AMay 5, 1987
Optical information processor for compensating offset
HITACHI LTD58 citations96
US5703855ADec 30, 1997
Optical disk apparatus and recording and reading method for an optical disk using the same
HITACHI LTD61 citations95
US5513165AApr 30, 1996
Method for controlling the farm of a magnetic domain of a magneto-optical disk using pre-write testing
HITACHI LTD90 citations95
US6721261B2Apr 13, 2004
Information recording/reproducing apparatus with laser driver
HITACHI LTD20 citations93
US6654328B2Nov 25, 2003
Information recording/reproducing apparatus with laser driver
HITACHI LTD27 citations93
US6552987B1Apr 22, 2003
Optical disk apparatus wherein recording clock signal is stopped being supplied to semiconductor laser drive circuit on optical pickup during reproduction operation
HITACHI LTD25 citations93
US6345023B1Feb 5, 2002
Optical disc apparatus with different frequencies of wobble signal and clock signal for rotation control
HITACHI LTD39 citations93
US5457666AOct 10, 1995
Light modulation method for forming a mark in magneto-optical recording system
HITACHI LTD53 citations93
US5270987ADec 14, 1993
Magneto-optical recording and reproducing method, magneto-optical memory apparatus and magneto-optical recording medium therefor
HITACHI LTD22 citations93
US5084860AJan 28, 1992
Apparatus for optical disc memory with correction pattern and master disc cutting apparatus
HITACHI LTD31 citations93
US4879703ANov 7, 1989
Magneto-optic memory apparatus with defect detection of recording medium during erasing operation
HITACHI LTD25 citations93
US4819242AApr 4, 1989
Semiconductor laser driver circuit
HITACHI LTD27 citations93
US4807210AFeb 21, 1989
Optical information processing apparatus
HITACHI LTD28 citations93
US4751695AJun 14, 1988
Method and apparatus for tracking servo system
HITACHI LTD27 citations93
US4730289AMar 8, 1988
Magnetic-optical disc memory system and apparatus for switching header and data information
HITACHI LTD27 citations93
US4622564ANov 11, 1986
Optical information recording apparatus
HITACHI LTD51 citations93
US4532522AJul 30, 1985
Optical recording apparatus
HITACHI LTD31 citations93
US6687208B2Feb 3, 2004
Laser drive integrated circuit and optical disk apparatus using the same
HITACHI LTD24 citations92
US6674702B2Jan 6, 2004
Laser drive integrated circuit and optical disk apparatus using the same
HITACHI LTD18 citations92
US6442118B1Aug 27, 2002
Information recording and reproducing apparatus having semiconductor laser drive circuitry in its pickup
HITACHI LTD38 citations92
US5629913AMay 13, 1997
Optical disk recording control method and apparatus for recording user data based on test signal
HITACHI LTD43 citations92
US5497361AMar 5, 1996
Information reproducing apparatus with a DC level correcting capability
HITACHI LTD32 citations92
US4450547AMay 22, 1984
Focal position detecting optical apparatus
HITACHI LTD53 citations92
US4742218AMay 3, 1988
Focus error detection apparatus utilizing focusing an front and rear sides of focal planes
HITACHI LTD44 citations91
US6636472B2Oct 21, 2003
Laser drive unit and information recording/reproducing apparatus
HITACHI LTD26 citations90
US6487154B1Nov 26, 2002
Laser drive unit and information recording/reproducing apparatus
HITACHI LTD32 citations90
US5339319AAug 16, 1994
Rotary type storage apparatus and control method thereof
HITACHI LTD20 citations89
US7227818B1Jun 5, 2007
Magneto-optical data recording/reproducing method
HITACHI LTD11 citations84
US6493297B1Dec 10, 2002
Multibeam optical disk record and reproduction apparatus and method
HITACHI LTD18 citations84
US6301211B1Oct 9, 2001
Information recording/reproducing apparatus
HITACHI LTD12 citations82
US4656618AApr 7, 1987
Optical information recording and reproducing apparatus
HITACHI LTD22 citations82
US4525826AJun 25, 1985
Optical track position detecting apparatus and optical information processor using the same
HITACHI LTD22 citations82
US6954410B2Oct 11, 2005
Information recording and reproducing apparatus for updating the waveform of a laser based on position information
HITACHI LTD10 citations74
US6442117B1Aug 27, 2002
Reading/reproducing apparatus having retry arrangement upon failed reading/writing of a signal
HITACHI LTD12 citations74
US6246661B1Jun 12, 2001
Optical disk recording and retrieving device
HITACHI LTD12 citations74
US6125093ASep 26, 2000
Optical disk recording and retrieving device
HITACHI LTD7 citations74
US5644554AJul 1, 1997
Magnetic head load/unload device, method and a magneto-optical disk apparatus using the same
HITACHI LTD11 citations74
US5412632AMay 2, 1995
Information reproducing apparatus with a DC level correcting capability
HITACHI LTD14 citations74
US5105409AApr 14, 1992
Method and apparatus for optical recording and reproduction with tracking servo reducing track offset
HITACHI LTD12 citations74
Showing the top 50 of 72 patents by PatentIndex Score.