A discharge lamp lighting device includes a control unit adapted to control a frequency of the AC electric current supplied to a discharge lamp by a feeding unit, in different manners within a first term and a second term which are alternately repeated, the control unit is adapted to control the frequency of the AC electric current such that, within the first term, the frequency of the AC electric current becomes at least one frequency out of plural set frequencies, and is further adapted to control the frequency of the AC electric current, based on a predetermined frequency and an electric current within the previous first term, such that, within the second term, the frequency of the AC electric current becomes a frequency lower than this predetermined frequency.

There is provide a discharge lamp lighting apparatus that comprises a discharge lamp and a power supply device configured to drive a regular lighting mode and the low electric power lighting mode in a switchable manner. The power supply device configured to control a power supply to the discharge lamp such that, in the low electric power lighting mode, after a secondary protrusion forming process in which an alternating current having a frequency equal to or greater than the basic frequency in the regular lighting mode is supplied, the low electric power lighting mode transitioning to a secondary protrusion maintaining process in which a high frequency alternating current having a frequency higher than the basic frequency in the regular lighting mode, and a low frequency alternating current having a frequency lower than the frequency of the high frequency alternating current is alternately supplied.

A method for lighting a high-pressure discharge lamp that is configured to change a power to be supplied to the high-pressure discharge lamp in accordance with a luminance parameter of an image content is disclosed. In the method, halogen is encapsulated in an internal space of an arc tube part of the high-pressure discharge lamp with an excessive volume with respect to a capacity of the internal space such that a halogen cycle is established when part of mercury deposits without vaporizing, and the internal space is configured to be kept at a higher temperature than a blackening temperature that is lower than a deposition temperature of the mercury and causes remarkable blackening on an inner wall of the arc tube part.