Issued Patents All Time
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4474440 | Slide projector having two image-projection systems which operate with a single slide tray | Albert S. Ballard | 1984-10-02 |
| 4466716 | Slide projector having two image-projection systems which operate with a single slide tray | Albert S. Ballard, Gideon A. Kramer | 1984-08-21 |
| 4416520 | Slide projector having two image-projection systems which operate with a single slide tray | — | 1983-11-22 |