Inventor · Yawata, JP

Nobuo Akahira

69Patents
21h-index
32Co-inventors
88Inventor score

Filing activity: Nov 18, 1976 → Feb 27, 2006

Most-cited inventions

PatentTitleAreaCited byStatus
US6456584B1 Optical information recording medium comprising a first layer having a phase that is reversibly changeable and a second information layer having a phase that is reversibly changeable Physics 99 Expired
US5097464A Optical recording medium and optical recording/reproducing apparatus Physics 91 Expired
US5568461A Optical information recording and reproducing apparatus Physics 71 Expired
US5764619A Optical recording medium having two separate recording layers Physics 70 Expired
US5109373A Optical information recording method Physics 69 Expired
US5216657A Method and apparatus for timing variable optical information recording Physics 52 Expired
US5745475A Optical information recording medium Physics 51 Expired
US5150351A Optical information recording apparatus for recording an input signal having variable width pulse duration and pulse spacing periods Physics 43 Expired
US5412626A Method of recording optical information with selective correction in pulse waveform and a recording system therefor Physics 39 Expired
US5635267A Optical information recording medium of phase change type having variably grooved tracks depending on their radial locations Emerging Cross-Sectional Technologies 38 Expired
US5811217A Optical information recording medium and optical information recording/reproducing method Emerging Cross-Sectional Technologies 35 Expired
US5493561A Optical information recording medium and information recording and reproducing method thereof Physics 34 Expired
US5545454A Optical information recording medium and method of designing its structure Emerging Cross-Sectional Technologies 33 Expired
US5898394A Code conversion method and apparatus, code recording medium, code recording apparatus and code reproducing apparatus Electricity 27 Expired
US4278734A Optical information recording material and method of recording and reproducing information using same material Emerging Cross-Sectional Technologies 26 Expired
US5305297A Method for determining optimum irradiation conditions in optical data recording Physics 26 Expired
US5249175A Optical information recording medium and information recording and reproducing method therefor Physics 25 Expired
US5154957A Optical information recording medium Emerging Cross-Sectional Technologies 25 Expired
US6031814A Optical disk with stop-pulse generating means in a guide groove Physics 25 Expired
US6487151B1 Optical information recording and reproducing system with overwrite capability and recording medium for use therewith Physics 25 Expired
US5272667A Optical information recording apparatus for recording optical information in a phase change type optical recording medium and method therefor Physics 23 Expired
US5289453A Optical information recording method Physics 21 Expired
US5348783A Optical information recording medium Emerging Cross-Sectional Technologies 21 Expired
US5424106A Optical information recording medium and method of designing its structure Emerging Cross-Sectional Technologies 20 Expired
US5410534A Optical information recording medium Physics 20 Expired

Source: USPTO / EPO open patent data. Inventor disambiguation is heuristic; counts are objective bibliographic measures.