Inventor · Yokohama, JP

Yoshihiro Kumagai

20Patents
8h-index
38Co-inventors
75Inventor score

Filing activity: Feb 14, 1989 → Jun 29, 2021

Most-cited inventions

PatentTitleAreaCited byStatus
US6750941B2 Complex diffraction device Physics 169 Expired
US6327089A Laminated transparent structure for reflective display Emerging Cross-Sectional Technologies 113 Expired
US4909777A Tensioner or toothed belts Mechanical Engineering; Lighting; Heating 22 Expired
US6628369B2 Circular polarizer and liquid crystal display Physics 18 Expired
US6292295A Rear projection screen incorporating a prism Physics 18 Expired
US6282034A Optical device and Fresnel lens sheet Physics 14 Expired
US5724188A Lenticular lens sheet Physics 11 Expired
US6210872A Optical film Physics 8 Expired
US6108465A Optical pulse generator Electricity 7 Expired
US5432636A Rear-projection screen Physics 6 Expired
US6101021A Optical pulse generator Electricity 4 Expired
US7019804B2 Liquid crystal cell with twist angle from 180 to 270 degrees and twisted optical compensating element Physics 4 Expired
US7061676B2 Rear projection screen and rear projection display apparatus Physics 2 Expired
US8724101B2 Optical fiber characteristic measuring device and method Physics 2 Active
US9221214B2 Method for producing concave-convex substrate using sol-gel method, sol used in same, method for producing organic EL element using same, and organic EL element obtained thereby Performing Operations; Transporting 1 Active
US9109977B2 Optical fiber characteristics measurement device and method Physics 1 Active
US11402296B2 Optical fiber characteristics measurement apparatus and optical fiber characteristics measurement method Physics 1 Active
US7136224B2 Rear projection screen with shifted lens Physics 0 Expired
US12339144B2 Optical fiber characteristic measurement device, optical fiber characteristic measurement program, and optical fiber characteristic measurement method for measuring characteristics of optical fiber based on Brillouin gain spectrum Physics 0 Active
US5432249A Liquid crystalline polyesters Chemistry; Metallurgy 0 Expired

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