Discharge lamp operation apparatus
US6963176B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 20, 2002 |
| Grant date | Nov 8, 2005 |
| Priority date | — |
| Expiry date | Jan 24, 2023 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S315/05
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A discharge lamp operation apparatus includes an AC power supply (10), a voltage converting circuit (11), an inverter circuit (13), a load circuit (15), a controller (1), and a pulse voltage superimposing section (3). The pulse voltage superimposing section (3) controls the switching elements (Q3, Q4) of the inverter circuit (13) to superimpose a pulse voltage to the voltage applied across the discharge lamp (LA). The period until the discharge lamp (LA) is lighted is divided into a preheating period to preheat the discharge lamp and a startup period to start the discharge lamp. During the startup period, the controller (1) raises gradually the output voltage (Vdc) of the voltage converting circuit (11), and the voltage superimposing section (3) superimposes the pulse voltage on the voltage applied across the discharge lamp (LA).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.