Visible spectrum

Electromagnetic Spectrum

The visible spectrum (or sometimes called the optical spectrum) is the part of the electromagnetic spectrum that is visible to the human eye. Electromagnetic radiation in this range of wavelengths is called visible light or simply light.

Laser beams with visible spectrum

A typical human eye will react to wavelengths in air from about 380 to 750 nm.

The familiar colors of the rainbow in the spectrum include all those colors that can be produced by visible light of a single wavelength only, the pure spectral or monochromatic colors.

But there are no clear boundaries between one color and the next.

Color display spectrum

Color	Wavelength	Frequency	Photon energy
violet	380–450 nm	668–789 THz	2.75–3.26 eV
blue	450–495 nm	606–668 THz	2.50–2.75 eV
green	495–570 nm	526–606 THz	2.17–2.50 eV
yellow	570–590 nm	508–526 THz	2.10–2.17 eV
orange	590–620 nm	484–508 THz	2.00–2.10 eV
red	620–750 nm	400–484 THz	1.65–2.00 eV

Color display spectrum. The narrow red, green and blue bars show the relative mixture of the three primary colors used to produce the color directly above.

Color displays (e.g., computer monitors or televisions) mix red, green, and blue color to approximate the color spectrum. In the illustration, the narrow red, green and blue bars show the relative mixture of these three colors used to produce the color directly above.

Visible Spectrum Media

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  White light is dispersed by a glass prism into the colors of the visible spectrum.

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  Newton's observation of prismatic colors (David Brewster 1855)

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  Photopic (black) and scotopic (green) luminous efficiency functions. The horizontal axis is wavelength in nm. See luminous efficiency function for more info.

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  Earth's atmosphere partially or totally blocks some wavelengths of electromagnetic radiation, but in visible light it is mostly transparent