The startup time of a lamp is the time a light source needs to reach at least 60% of its total brightness. How long this takes depends on the type of lamp:

• Incandescent lamps, halogen lamps, and LED lamps reach full brightness almost immediately.

• Energy-saving lamps typically need 90 seconds to reach full brightness.

Practical example: are you looking for a lamp for a storage cupboard? Then the first three types (incandescent, halogen, or LED) are a better choice because you have immediate access to full light output.