Original: Black light CFLs , those with UVA generating phosphor , are much more efficient than incandescent black light lamps , since the amount of UV light that the filament of the incandescent lamp produces is only a fraction of the generated spectrum .
Simplified: The purchase price of a CFL is often much higher than an incandescent lamp of the same output , and the light from CFLs looks different to light from incandescent lamps .