Issued Patents All Time
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5117679 | Testing apparatus and method | Kenneth Lewtas, Edwin William Lehmann, John N. Mears, Brian Wiggins | 1992-06-02 |
| 5113375 | Method and apparatus for testing geophones | — | 1992-05-12 |