Granted Patent
Utility
US 4,889,409 · App. 07/156,185
Hemispherical retroreflector
Inventor:
Paul D. Atcheson
Patented Case
View Patent ↗
Granted: Dec 26, 1989
Filed: Feb 16, 1988
Inventor
Paul D. Atcheson
Assignee (at issue)
BALL 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.