Granted Patent
Utility
US 4,837,582 · App. 07/138,947
Method and apparatus for detecting electromagnetic waves generated by the earth's crust under strain
Inventors:
Kozo Takahashi, Yoshihisa Masuda, Hisao Inuki
Patented Case
View Patent ↗
Granted: Jun 6, 1989
Filed: Dec 29, 1987
Inventors
Kozo Takahashi
Yoshihisa Masuda
Hisao Inuki
Assignees (at issue)
Communications Research Laboratory, Inc.
Ministry of Posts and Telecommunications
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.