The light from an incandescent light bulb is produced by a solid metal filament of Tungsten wire through which an
electric current is passed. The current heats the filament to an extremely high temperature (typically 2000 to 3000 K) producing a
thermal blackbody spectrum with a peak intensity in the near infrared (1000 - 1500 nm). Although the peak is not in the visible region,
there is still enough energy emitted at visible wavelengths to produce light useful to the eye (although this light is much "yellower" than the
white light of the Sun which has a temperature of about 5800 K).
Spectrum of Incandescent Light Bulb