Issued Patents All Time
Showing 1–20 of 20 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 6239556 | Long life discharge lamp operating circuit with reduced lamp flicker | Gunther Hans Derra, Hanns E. Fischer, Thomas Krücken, Holger Moench, Rob Snijkers | 2001-05-29 |
| 6232725 | Circuit arrangement for operating a high-pressure discharge lamp | Gunther Hans Derra, Hanns E. Fischer, Thomas Krücken, Holger Moench, Rob Snijkers | 2001-05-15 |
| 6111765 | Discharge lamp operating circuit using piezoelectric transformer and protective device | Dieter Leers, Klaus Lohn, Martin Ossmann, Pieter Postma | 2000-08-29 |
| 6104141 | Inventer-ballast using a piezoelectric transformer | Dieter Leers, Klaus Lohn, Martin Ossmann, Pieter Postma | 2000-08-15 |
| 5689156 | Circuit arrangement for detecting the amount of deposited electrode material on the wall of a lamp vessel | Gunther Hans Derra, Hanns E. Fischer, Holger Monch | 1997-11-18 |
| 5608294 | High pressure lamp operating circuit with suppression of lamp flicker | Gunther Hans Derra, Hanns E. Fischer, Holger Monch | 1997-03-04 |
| 5262701 | Circuit arrangement for operating a high pressure sodium lamp | Gunther Hans Derra, Hans Peter Stormberg | 1993-11-16 |
| 5025197 | Circuit arrangement for A.C. operation of high-pressure gas discharge lamps | Ralf Schafer, Hans Peter Stormberg | 1991-06-18 |
| 4994716 | Circuit arrangement for starting and operating gas discharge lamps | Ralf Schafer, Hans Peter Stormberg | 1991-02-19 |
| 4937501 | Circuit arrangement for starting a high-pressure gas discharge lamp | Hans Peter Stormberg | 1990-06-26 |
| 4891563 | Circuit arrangement for adjusting the operating voltage of high-pressure gas discharge lamps | Ralf Schafer, Hans Peter Stormberg | 1990-01-02 |
| 4888524 | Circuit for operating gas discharge lamps with a periodically alternating lamp current | Ralf Schafer, Hans Peter Stormberg | 1989-12-19 |
| 4839560 | Heatable electrode for high-pressure gas discharge lamps | Ralf Schafer, Hans Peter Stormberg | 1989-06-13 |
| 4816721 | Circuit arrangement for operating a high-pressure gas discharge lamp | Ralf Schafer, Hans Peter Stormberg | 1989-03-28 |
| 4748381 | Circuit arrangement for A.C. operation of gas discharge lamps | Ralf Schafer, Hans Peter Stormberg | 1988-05-31 |
| 4714862 | Circuit arrangement for igniting and operating gas discharge lamps | Horst Dannert, Ralf Schafer, Hans Peter Stormberg | 1987-12-22 |
| 4705991 | Method of operating a high-pressure metal vapor discharge lamp and circuit arrangement for carrying out this method | Reinhard Kersten, Rolf Schafer, Hans Peter Stormberg | 1987-11-10 |
| 4594531 | Circuit arrangement for operating high-pressure gas discharge lamps | Ralf Schafer, Hans Peter Stormberg | 1986-06-10 |
| 4539513 | Circuit arrangement for starting and operating a high-pressure gas discharge lamp | Ralf Schafer, Hans Peter Stormberg | 1985-09-03 |
| 4471269 | Circuit arrangement for operating a high-pressure gas discharge lamp | Ralf Sch/a/ fer, Hans Peter Stormberg | 1984-09-11 |