RK

Ritsuo Koga

PR Prevent-Plus: 5 patents #6 of 68Top 9%
ZC Zero Lab Co.: 5 patents #1 of 2Top 50%
Overall (All Time): #496,696 of 4,157,543Top 15%
10
Patents All Time

Issued Patents All Time

Patent #TitleCo-InventorsDate
11769429 Magnetic erasing device 2023-09-26
11335487 Magnetic eraser, writing system and display device 2022-05-17
10997880 Magnetic erasing device 2021-05-04
10442236 Magnetic pen 2019-10-15
10046592 Magnetic pen 2018-08-14
6340237 Lamp cartridge Hideto Kubouchi 2002-01-22
6129437 Image display apparatus Hideto Kubouchi 2000-10-10
5803449 Automatic manuscript sheet feeder Kouichi Minami 1998-09-08
4979813 Opaque projector Kuroudo Hara 1990-12-25
4802014 Portable transfer apparatus 1989-01-31