Issued Patents All Time
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5274401 | Electrostatic printhead | David E. Doggett, Gordon S. Mitchard | 1993-12-28 |
| 5148595 | Method of making laminated electrostatic printhead | David E. Doggett | 1992-09-22 |
| 5062002 | Electrostatic printer with color hue or grey level controlled by the level and/or duty cycle of voltages applied to each styli | David E. Doggett, Gordon S. Mitchard | 1991-10-29 |
| 4672399 | Contrast control for an electrostatic printer | — | 1987-06-09 |