Issued Patents 1989
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4840281 | Tamper evident optical device and article utilizing the same | Roger W. Phillips, Vernon C. Spellman, Wayne L. Gossett, Marc A. Kamerling | 1989-06-20 |
| 4838648 | Thin film structure having magnetic and color shifting properties | Roger W. Phillips | 1989-06-13 |