Subject: How long does it take a light bulb to light up?

My question is something I have become interested in because of the new photo
redlight cameras that governments are mounting at intersections.  Driver's get a
photograph of them in an intersection and a number box that says the light has
been red for x seconds(some as low  as .4 seconds), so you ran the redlight. 
The device that measures this starts when the electricity switches on for the
redlight.  My question is once the electricity hits the bulb how long will it
take for the element to get hot enough for the bulb to transmit light at its
brightest?  

Re: How long does it take a light bulb to light up?