IP Library Granted Patent US 6,820,489
Granted Patent Utility
US 6,820,489 · App. 10/646,368

Optical differential pressure sensor

Inventors: Mark R. Fernald, Timothy J. Bailey, Matthew B. Miller, James M. Sullivan, James Dunphy, Michael A. Davis, Christopher J. Wright, Alan D. Kersey, Martin A. Putnam, Robert N. Brucato, Paul E. Sanders
Patented Case View Patent ↗
Granted: Nov 23, 2004 Filed: Aug 22, 2003
Inventors
Mark R. Fernald
Timothy J. Bailey
Matthew B. Miller
James M. Sullivan
James Dunphy
Michael A. Davis
Christopher J. Wright
Alan D. Kersey
Martin A. Putnam
Robert N. Brucato
Paul E. Sanders
Assignee (at issue)
Weatherford/Lamb, 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.

Order Certified Copies
Most orders are placed with the USPTO same day — all within 24 business hours.
Order via The Patent Place →
Pre-filled with this patent's details
Quick Facts
Patent No.
US 6,820,489
App. No.
10/646,368
Filed
2003-08-22
Granted
2004-11-23
Kind
B2