Discharge-lamp control device
US7218059B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 20, 2005 |
| Grant date | May 15, 2007 |
| Priority date | — |
| Expiry date | Nov 11, 2025 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05B41/2822
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A discharge-lamp control device for lighting a discharge-lamp includes two electrodes, first and second driving units to supply power to the discharge-lamp through the electrodes, respectively. Each driving unit includes a transformer having primary and secondary coils and a capacitor connected in parallel to the secondary coil. The first driving unit has impedance characteristics with a minimum impedance at a first frequency and a maximum impedance at a second frequency lower than the first frequency. The second driving unit has impedance characteristics having a minimum impedance at a third frequency and a maximum impedance at a fourth frequency lower than the third frequency. The first frequency is set to be higher than the third frequency. The second frequency is set to be lower than the fourth frequency. An operating frequency of the driving circuit is selected within a frequency bandwidth from the fourth frequency to the third frequency.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.