Nitrogen
If you mean which other element is used in a fluorescent light along with argon then the answer is xenon.
argon
Mercury Vapor
mercury
Argon(or nitrogen) and tungsten are used in incandescent light bulbs.
argon (Ar)
its used for light bulbs, radio tubes, and welding.
argon or noble gases
mainly in light bulbs, also to make a purple light.
They are known as CFL bulbs. It stands for Compact Fluorescent Lamps.
Light in fluorescent bulbs occurs when electricity excites the mercury vapor inside the tubular glass bulb.
used as filling for fluorescent lamps, electric light bulbs, incandescent lamps and for vacuum tube.