SY

Seiji Yonezawa

HI Hitachi: 4 patents #64 of 2,935Top 3%
Overall (1989): #3,791 of 140,708Top 3%
4
Patents 1989

Issued Patents 1989

Showing 1–4 of 4 patents

Patent #TitleCo-InventorsDate
4872152 Light spot position control system and method by sampled servo Toshiaki Tsuyoshi, Masatoshi Ohtake, Wasao Takasugi 1989-10-03
4866688 Composite tracking servo system for optical disc apparatus with track offset correction Masatoshi Ohtake, Toshiaki Tsuyoshi, Kazuo Ichino, Yukio Fukui, Takashi Takeuchi +2 more 1989-09-12
4857744 Optical projection printing apparatus wherein wafer mark has a grating pitch in the sagittal plane of the first optical system Keiji Kataoka, Toshiei Kurosaki, Soichi Katagiri 1989-08-15
4847822 Optical information recording and reproducing apparatus with tracking control by sampling Wasao Takasugi, Toshiaki Tsuyoshi, Masatoshi Ohtake 1989-07-11