Metal halide lamps with fast run-up and methods of operating the same

An apparatus, comprising:

• a metal halide lamp, the metal halide lamp comprising:
• a discharge vessel comprising a discharge space;
• at least one electrode assembly extending into the discharge vessel in a sealed fashion to be in contact with the discharge space, the at least one electrode assembly comprising an electrode tip and a feedthrough, the electrode tip having a current rating C1;
• at least one fill gas in the discharge space;
• at least one fill material in the discharge space, the fill material comprising at least one first metal halide;
• and
• at least one volatile material other than the fill material in the discharge space, wherein the at least one volatile material has a higher vapor pressure than the at least one first metal halide
• wherein:
• the metal halide lamp has a first voltage Vi at ignition, a power Preq, a second voltage Vs, and a current Is during steady state operation;
• Preq=Vs*Is;
• Vs/Vi is less than or equal to about 3.33;
• and
• the electrode tip is sized or otherwise configured such that C1 is greater than or equal to Is.

A metal halide lamp, comprising:

• a discharge vessel comprising a discharge space;
• at least one electrode assembly extending into the discharge vessel in a sealed fashion to be in contact with the discharge space, the at least one electrode assembly comprising an electrode tip and a feedthrough, the electrode tip having a current rating C1;
• at least one fill gas in the discharge space;
• and
• at least one fill material in the discharge space, the fill material comprising at least one first metal halide;
• at least one volatile material in the discharge space, the at least one volatile material being selected from the group consisting of mercury, at least one second metal halide having a higher vapor pressure than the first metal halide, and combinations thereof
• wherein:
• the metal halide lamp has a first voltage Vi at ignition, a power Preq, a second voltage Vs, and a current Is during steady state operation;
• Preq=Vs*Is;
• Vs/Vi is less than or equal to about 3.33;
• and
• the electrode tip is sized or otherwise configured such that C1 is greater than or equal to Is.

A method of operating a metal halide lamp comprising:

• providing a metal halide lamp comprising:
• a discharge vessel comprising a discharge space;
• at least one electrode assembly extending into the discharge vessel in a sealed fashion to be in contact with the discharge space, the at least one electrode assembly comprising an electrode tip and a feedthrough, the electrode tip having a current rating C1;
• at least one fill gas in the discharge space;
• and
• at least one fill material in the discharge space, the fill material comprising at least one first metal halide;
• at least one volatile material in the discharge space, the at least one volatile material being selected from the group consisting of mercury, at least one second metal halide having a higher vapor pressure than the first metal halide, and combinations thereof;
• wherein:
• the metal halide lamp has a first voltage Vi at ignition, a power Preq, a second voltage Vs, and a current Is during steady state operation;
• Preq=Vs*Is;
• Vs/Vi is less than or equal to about 3.33;
• and
• the electrode tip is sized or otherwise configured such that C1 is greater than or equal to about Is;
• igniting the metal halide lamp;
• running up the metal halide lamp to steady state operation;
• and
• maintaining the metal halide lamp at steady state operation by applying Preq to the at least one electrode assembly.