Inventor
KOYANAGI HIROAKI
JP15 patents
⚠️ This page may combine multiple inventors who share the name “KOYANAGI HIROAKI”. Patents are grouped by organization below to help distinguish them — per-person disambiguation is on the roadmap.
HITACHI LTD
14 patentsUS5018072AMay 21, 1991
Optically readable mail system with general and receiver specific information
HITACHI LTD133 citations97
US5701221ADec 23, 1997
Magnetoresistive thin-film magnetic head and method of fabrication thereof
HITACHI LTD41 citations92
US5471358ANov 28, 1995
Thin film magnetoresistive head which includes a domain suppressing layer and method for manufacturing the same
HITACHI LTD20 citations92
US5177717AJan 5, 1993
Optical memory medium and its information recording and erasing method and apparatus
HITACHI LTD32 citations92
US4978187ADec 18, 1990
Optical element, optical disc and rotary encoder with the optical element
HITACHI LTD41 citations92
US4937808AJun 26, 1990
Intergrated optical head with flexible substrate portion
HITACHI LTD40 citations92
US4811328AMar 7, 1989
Optical recording and reproducing device
HITACHI LTD30 citations92
US4773060ASep 20, 1988
Optical information recording device
HITACHI LTD44 citations92
US5894380AApr 13, 1999
Recording/reproducing separation type magnetic head
HITACHI LTD17 citations89
US4718053AJan 5, 1988
Optical information apparatus and method of recording and erasing information
HITACHI LTD23 citations81
US5110792AMay 5, 1992
Method and apparatus of optical modulation using superconductive oxide material
HITACHI LTD16 citations74
US4862440AAug 29, 1989
Optical head with optical beam control using acoustic wave device
HITACHI LTD12 citations74
US5897969AApr 27, 1999
Method of fabricating a magnetoresistive thin-film magnetic head
HITACHI LTD14 citations73
USRE37785EJul 9, 2002
Recording/reproducing separation type magnetic head
HITACHI LTD3 citations59