When discussing light, a spectrum is a linear scale of spectral colours organised by wavelength.
- A visible spectrum of colours is produced naturally when light is refracted by a prism or by raindrops.
- The plural of spectrum is spectra.
- The continuous distribution of colours in a spectrum is a result of the fact that visible light consists of a range of wavelengths, rather than distinct, separate colours.
- A diagram of spectral colours is usually presented in the form of a spectrum, a linear band organised by wavelength with red at one end and violet at the other.
- Spectra are often shown in an elongated form so that as many different gradations of colour can be seen as possible.
- The process of separating light into its constituent colours is called dispersion.
Related diagrams
Each diagram below can be viewed on its own page with a full explanation.
