| 20110063584 | High pressure discharge lamp lighting apparatus and projector - A discharge lamp lighting apparatus comprises a discharge lamp and a power supply the discharge lamp can be switched between a steady power lighting mode, which drives the discharge lamp by an alternating current in which first and second polarities are repeated by turns, and a low power lighting mode, which drives the discharge lamp at 50% or less of the alternating current of the steady power lighting mode, and the alternating current comprises a first time unit, which has a time width t | 03-17-2011 |
