Patent ID: 8067903

Claim:
A method for driving a gas discharge lamp in at least a first and a second operation modes, the method comprising applying an alternating voltage to the gas discharge lamp, the alternating voltage having a first polarity during a first time interval and a second polarity opposite to the first polarity during a second time interval, the first time interval and the second time interval being repeated alternately, wherein in the second operation mode, the electrical power being provided to the gas discharge lamp is smaller compared to the first operation mode, and the duration of the first time interval is at least a multiple of the duration of the second time interval, and wherein, in the second operation mode, the electrical power being provided to the gas discharge lamp is reduced to a level leading to temperature and/or pressure levels inside an arc tube of the gas discharge lamp that enable to turn off the gas discharge lamp completely, while maintaining the ability to re-ignite the gas discharge lamp essentially immediately.