Granted Patent
Utility
US 6,180,894 · App. 09/074,640
Dual mode digitizer tablet system
Inventors:
Ching-Chuan Chao, Chia-Jui Yeh
Patented Case
View Patent ↗
Granted: Jan 30, 2001
Filed: May 7, 1998
Inventors
Ching-Chuan Chao
Chia-Jui Yeh
Assignee (at issue)
Aiptek International GmbH
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.