Granted Patent
Utility
US 6,597,642 · App. 09/709,929
Photodetector unit, and optical pickup, optical reproduction apparatus, and optical recording apparatus equipped with the same
Inventors:
Shinichi Ijima, Shoichi Takasuka, Hideyuki Nakanishi, Akio Yoshikawa
Patented Case
View Patent ↗
Granted: Jul 22, 2003
Filed: Nov 10, 2000
Inventors
Shinichi Ijima
Shoichi Takasuka
Hideyuki Nakanishi
Akio Yoshikawa
Assignee (at issue)
SUMITOMO ELECTRIC INDUSTRIES, LTD.
This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.