Granted Patent
Utility
US 5,083,240 · App. 07/694,466
Light guide
Inventor:
Ian K. Pasco
Patented Case
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Granted: Jan 21, 1992
Filed: May 1, 1991
Inventor
Ian K. Pasco
Assignee (at issue)
Technophone Limited
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.