High-pressure discharge lamp and lighting method

A high-pressure discharge lamp comprising:

• an outer envelope of light-translucent material;
• a plurality of arc tubes enclosed in said outer envelope and electrically connected in parallel with each other;
• and
• a plurality of ignition aids available for assisting operating of respective arc tubes, wherein said ignition aids are at different electrical potentials, and
• wherein said plurality of arc tubes have longitudinal axes and are disposed within said outer envelope such that said longitudinal axes form an angle with respect to one another.

An apparatus for operating a high-pressure discharge lamp comprising:

• an outer envelope incorporating a pair of electric terminals;
• a high-pressure discharge lamp comprising said outer envelope incorporating a pair of electric terminals, a plurality of arc tubes enclosed in said outer envelope and electrically connected to said pair of terminals in parallel, and a plurality of ignition aids for assisting operation of respective arc tubes, wherein said arc tubes have different electrical potentials;
• an AC power supply source for supplying an AC voltage;
• first and second power-supply means respectively connecting both terminals of said AC power supply source to said pair of terminals;
• a ballast being at least connected on either of said first and second power supply means;
• a pulse generating means generating at least positive or negative ignition pulses for superimposing on said AC voltage delivered from said AC power supply source;
• and
• a control means for selecting either positive or negative ignition pulses output from said pulse generating means for superimposing on said AC voltage.