Granted Patent
Utility
US 4,884,939 · App. 07/138,301
Self-contained laser-activated depth sensor for excavator
Inventor:
Edward G. Nielsen
Patented Case
View Patent ↗
Granted: Dec 5, 1989
Filed: Dec 28, 1987
Inventor
Edward G. Nielsen
Assignee (at issue)
Laser Alignment, Inc.
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.