Issued Patents 1989
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4864189 | Control plate for display devices | — | 1989-09-05 |
| 4838651 | Projection tube having an insulating layer of magnesium oxide and a high transmission metal grating | Jurgen Pottharst | 1989-06-13 |