What is broadband?

Broadband is an adjective used to describe light sources with a large wavelength range. While there is no clear cut numerical definition, hundreds of nanometers is usually called broadband. Many lamp sources, such as tungsten halogen lamps, are broadband. Lasers can also be broadband; Ti:sapphire lasers are an example of this. However, most common lasers have such a small wavelength range that they are considered monochromatic.