Granted Patent
Utility
US 5,990,608 · App. 08/975,248
Electron gun having a cathode with limited electron discharge region
Inventor:
Tetsuya Shiroishi
Patented Case
View Patent ↗
Granted: Nov 23, 1999
Filed: Nov 21, 1997
Inventor
Tetsuya Shiroishi
Assignee (at issue)
MITSUBISHI ELECTRIC CORPORATION
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.