| 9470808 |
Micro-geophone |
— |
2016-10-18 |
| 9297916 |
Micro-geophone |
— |
2016-03-29 |
| 8976627 |
Micro-geophone |
— |
2015-03-10 |
| 8947980 |
Micro-geophone |
— |
2015-02-03 |
| 8208347 |
Geophone having improved damping control |
— |
2012-06-26 |
| 8098546 |
Geophone having improved sensitivity |
— |
2012-01-17 |
| 8050144 |
Vertical geophone having improved distortion characteristics |
— |
2011-11-01 |
| 7369716 |
High pressure and high temperature acoustic sensor |
Arne Berg, Sverre Knudsen, Geir Bjarte Havsgard, James Dunphy |
2008-05-06 |
| 7116850 |
Hydrophone mandrel for precise placement of gratings |
— |
2006-10-03 |
| 7082079 |
Pressure compensated hydrophone |
— |
2006-07-25 |
| 7013729 |
Highly sensitive accelerometer |
Sverre Knudsen, Arne Berg, James Dunphy |
2006-03-21 |
| 6882595 |
Pressure compensated hydrophone |
— |
2005-04-19 |
| 6789424 |
Highly sensitive accelerometer |
Sverre Knudsen, Arne Berg, James Dunphy |
2004-09-14 |
| 6575033 |
Highly sensitive accelerometer |
Sverre Knudsen, Arne Berg, James Dunphy |
2003-06-10 |
| 5555222 |
Low distortion geophone spring |
— |
1996-09-10 |
| 5469408 |
High resolution geophone |
— |
1995-11-21 |
| 5450375 |
Geophone shock absorber |
— |
1995-09-12 |
| 5134594 |
Geophone spring |
— |
1992-07-28 |
| 5119345 |
Geophone |
James C. Woodall |
1992-06-02 |