Issued Patents All Time
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 6552485 | Electron tube comprising a semiconductor cathode | Frederik C. Gehring, Tom Van Zutphen | 2003-04-22 |
| 6236154 | Electron tube with a cesium source | Tom Van Zutphen, Frederik C. Gehring | 2001-05-22 |
| 6198210 | Electron tube having a semiconductor cathode with lower and higher bandgap layers | Tom Van Zutphen, Erwin Hijzen | 2001-03-06 |
| 6166485 | Electron gun with heat dissipation elements | Maarten H. Zonneveld, Edwin Heijman, Arnold Sinke | 2000-12-26 |
| 6064074 | Semiconductor cathode and electron tube comprising a semiconductor cathode | Tom Van Zutphen, Frederik C. Gehring, Mark A. De Samber, Erwin Hijzen | 2000-05-16 |
| 5880481 | Electron tube having a semiconductor cathode with lower and higher bandgap layers | Tom Van Zutphen, Erwin Hijzen | 1999-03-09 |