Light Source Continuous Spectrum

Spectrum of light emitted by a deuterium lamp showing a discrete part tall sharp peaks and a continuous part smoothly varying between the peaks.

Light source continuous spectrum.

Truly white light like that emitted by some stars and moons is a perfect example of continuous spectrum. Similar phenomena occur in high pressure arc lamps in which broadening of spectral lines occurs owing to high collision rates. When an absorption spectrum and emission spectrum are combined you get a continuous spectrum with all the wavelengths. A good example of a almost exclusively single wavelength source of non incandescent visible light is the sodium vapor lamps commonly employed in street lighting.

As a consequence these sources do not produce the continuous spectrum of illumination that is characteristic of incandescent sources. The sun s light is also believed to produce continuous spectrum since we can see the rainbow. The smaller peaks and valleys may be due to measurement errors rather than discrete spectral lines. Stars and stellar spectra.

Broadband light sources then overlap and form a continuous i e nondiscrete spectrum. The term full spectrum is not a technical term but rather a marketing term implying a smooth and continuous spectral power distribution spd without the spikes and troughs in radiant energy common with most discharge light sources e g fluorescent and metal halide.