Granted Patent
Utility
US 5,108,177 · App. 07/581,237
Two-axis levelling instrument with a single pendulum for projecting a level laser beam
Inventor:
Michael Middleton
Patented Case
View Patent ↗
Granted: Apr 28, 1992
Filed: Sep 12, 1990
Inventor
Michael Middleton
Assignee (at issue)
LASERLINE 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.