All LEDs, from LED kitchen lighting to outdoor LED fixtures are “instant-on” and “instant-off.” Anyone who has used halogen lights, fluorescent lights, or the smaller CFLs (compact fluorescent lights) will be familiar with the flickering, slow powering up of these other energy efficient lights. It is a common frustration. LEDs do not have this “warming up” problem, and reach full power and luminosity in a matter of milliseconds. They also turn off without the flickering and warming down that is common with other types of non-incandescent lighting.
The phrase “warm up” is a misnomer in the case of LEDs, as they generate very little heat, and don’t feel significantly warmer in temperature when they are activated than they do when switched off. This convenience stems from the same technology that makes them so energy efficient, as it does not have to push electricity through to excite any type of substance.