P

Inventor

YONEZAWA SEIJI

JP48 patents
⚠️ This page may combine multiple inventors who share the name “YONEZAWA SEIJI”. Patents are grouped by organization below to help distinguish them — per-person disambiguation is on the roadmap.

HITACHI LTD

44 patents
US5959943ASep 28, 1999

Information recording medium with clock information therein

HITACHI LTD69 citations96
US5150339ASep 22, 1992

Optical disk medium and its application method and system

HITACHI LTD87 citations96
US4866688ASep 12, 1989

Composite tracking servo system for optical disc apparatus with track offset correction

HITACHI LTD111 citations96
US4791627ADec 13, 1988

Wobbled pit recording method and device of optical recording medium utilizing a plurality of time different signal waveforms

HITACHI LTD77 citations96
US4748609AMay 31, 1988

Method and apparatus for composite tracking servo system with track offset correction and rotary optical disc having at least one correction mark for correcting track offset

HITACHI LTD119 citations96
US4707816ANov 17, 1987

Method and apparatus for composite wobbled and push-pull tracking servo system

HITACHI LTD98 citations96
US4357616ANov 2, 1982

Recording medium

HITACHI LTD72 citations96
US4333173AJun 1, 1982

Optical information processor with prismatic correction of laser beam shape

HITACHI LTD61 citations96
US5296995AMar 22, 1994

Method of magnetically recording and reading data, magnetic recording medium, its production method and magnetic recording apparatus

HITACHI LTD58 citations95
US5348837ASep 20, 1994

Projection exposure apparatus and pattern forming method for use therewith

HITACHI LTD73 citations94
US5134426AJul 28, 1992

Optical device for generating pattern having uniform light intensity distribution

HITACHI LTD29 citations93
US4759628AJul 26, 1988

Wavelength scanning interferometry and interferometer employing laser diode

HITACHI LTD25 citations93
US4785442ANov 15, 1988

Light spot position control system and method by sampling servo

HITACHI LTD38 citations92
US4703408AOct 27, 1987

Apparatus and record carrier for optically writing information

HITACHI LTD27 citations92
US4564929AJan 14, 1986

Information recording and reproducing apparatus with tracking control by sampling

HITACHI LTD30 citations92
US4392219AJul 5, 1983

Method and device for recording and reproducing tracking information

HITACHI LTD33 citations92
US4748611AMay 31, 1988

Information recording medium and method for reproducing the same

HITACHI LTD29 citations89
US4067044AJan 3, 1978

Information recording and retrieval apparatus

HITACHI LTD59 citations89
US5170383ADec 8, 1992

Magneto-optical data recording system

HITACHI LTD13 citations82
US4949325AAug 14, 1990

Method and associated apparatus and medium for optical recording and reproducing information

HITACHI LTD22 citations82
US4857744AAug 15, 1989

Optical projection printing apparatus wherein wafer mark has a grating pitch in the sagittal plane of the first optical system

HITACHI LTD22 citations82
US4411500AOct 25, 1983

Optical system for reproducing information

HITACHI LTD22 citations82
US4364118ADec 14, 1982

Optical disk and optical information processor

HITACHI LTD24 citations82
US4238803ADec 9, 1980

Information recording methods using lasers

HITACHI LTD27 citations82
US5886958AMar 23, 1999

Information recording apparatus and method for modulated magneto-optical recording medium

HITACHI LTD3 citations74
US5726955AMar 10, 1998

Magneto optical recording medium apparatus and method utilizing light pulse magnetic modulation recording

HITACHI LTD4 citations74
US5473581ADec 5, 1995

Magneto-optical data recording system continuously irradiating optical pulsers

HITACHI LTD7 citations74
US4872152AOct 3, 1989

Light spot position control system and method by sampled servo

HITACHI LTD18 citations74
US4688880AAug 25, 1987

Hologram lens

HITACHI LTD11 citations74
US4646279AFeb 24, 1987

Optical disk cutting apparatus using multiple beams

HITACHI LTD8 citations74
US4504937AMar 12, 1985

Optical information tracking apparatus

HITACHI LTD11 citations74
US4407880AOct 4, 1983

Substrate of member for recording information with light and method of manufacturing the same

HITACHI LTD13 citations74
US4348461ASep 7, 1982

Recording member

HITACHI LTD7 citations74
US4296419AOct 20, 1981

Member for recording information

HITACHI LTD7 citations74
US4235507ANov 25, 1980

Optical system to condense light from a semiconductor laser into a circular spot

HITACHI LTD10 citations74
US4710909ADec 1, 1987

Phase compensation apparatus for an optical information recording and reproducing system

HITACHI LTD11 citations73
US4223187ASep 16, 1980

Method and apparatus for recording and reproducing a video-disc with an oscillated track

HITACHI LTD17 citations73
US4541082ASep 10, 1985

Device for optically tracking information

HITACHI LTD8 citations72
US6205098B1Mar 20, 2001

Optical reproduction method and optical information apparatus

HITACHI LTD3 citations63
US5579292ANov 26, 1996

Magneto-optical data recording apparatus using a sample-servo system for applying heating pulses to record data

HITACHI LTD2 citations63
US4847822AJul 11, 1989

Optical information recording and reproducing apparatus with tracking control by sampling

HITACHI LTD4 citations63
US4241240ADec 23, 1980

Optical information recording apparatus

HITACHI LTD3 citations62
US6614737B2Sep 2, 2003

Optical reproduction method and optical information device

HITACHI LTD1 citations52
US6442120B2Aug 27, 2002

Optical reproduction method and optical information device

HITACHI LTD0 citations52

COMETS INC

2 patents

(unassigned)

1 patent

YONEZAWA SEIJI

1 patent