Issued Patents All Time
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 6698908 | Lighting fixture optical assembly including relector/refractor and collar for enhanced directional illumination control | Ronald L. Sitzema, Jr. | 2004-03-02 |
| RE38217 | Tubular skylight with improved dome | David A. DeBlock, Ronald L. Sitzema, Jr. | 2003-08-19 |