Inventor · Tokyo, JP

Koichi Maruyama

139Patents
19h-index
101Co-inventors
89Inventor score

Filing activity: Nov 29, 1972 → Feb 9, 2021

Most-cited inventions

PatentTitleAreaCited byStatus
US8570668B2 Imaging optical system and imaging apparatus Physics 118 Active
US6118594A Objective lens for optical pick-up Physics 81 Expired
US6191889A Objective lens for optical pick-up Physics 55 Expired
US5838496A Diffractive multi-focal objective lens Physics 50 Expired
US5629799A Chromatic aberration correcting element and its application Physics 47 Expired
US5991102A Beam protecting device Physics 35 Expired
US5461513A Image stabilizing apparatus Physics 29 Expired
US5039211A Zoom lens capable of image blur compensation Physics 28 Expired
US5297114A Magneto-optic recording/reproduction apparatus for minimizing variation in focusing error signals caused by variation in optical source wavelength Physics 27 Expired
US4948233A Beam shaping optical system Physics 25 Expired
US5280387A Image stabilizing apparatus Physics 25 Expired
US4848883A Telephoto zoom lens system having four lens groups Physics 24 Expired
US5796520A Chromatic aberration correcting element and its application Physics 23 Expired
US5825555A Beam projecting apparatus Physics 22 Expired
US6807019B2 Objective lens having diffractive structure for optical pick-up Physics 22 Expired
US5121978A Image blur compensating telephotographic lens Physics 21 Expired
US6130785A Eyepiece lens system Physics 20 Expired
US5321550A Optical system of optical information recording/reproducing apparatus Physics 19 Expired
US6594222B2 Objective lens for optical pick-up Physics 19 Expired
US6760295B1 Optical pick-up Physics 18 Expired
US6344935B1 Optical system of optical pick-up Physics 18 Expired
US4142131A Color picture tube Electricity 17 Expired
US6101035A Triplet lens system with diffractive lens features Physics 17 Expired
US5173809A Objective lens system of optical information recording/reproducing apparatus Physics 17 Expired
US5278401A Optical disc apparatus having five light receiving areas for detecting focus error and tracking error Physics 17 Expired

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