Why do fluorescent lights take so long to warm up?
One of the byproducts of mercury vapor and argon gas is
luminescence or light. The bulb is full of gas and when you turn on
the switch, the starter will fire an electrical charge on both ends
of the bulb exciting the gas inside and a small amount of mercury
emits vapor and the gas molecules collide and excite more molecules
nearby until the entire contents are excited. This makes the bulb
get brighter until it reaches its maximum brightness. The white
phosphorous coating inside the bulb increases illumination. If It
didnt have this powder coating, It would be a black light. In
cooler temperatures, you can see the pulses of the light as it goes
from one end to the other in waves. Tha average bulb reaches full
brightness in about 15-20 seconds on average.