<P> The visible spectrum is the portion 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 . A typical human eye will respond to wavelengths from about 390 to 700 nm . In terms of frequency, this corresponds to a band in the vicinity of 430--770 THz . </P> <P> The spectrum does not, however, contain all the colors that the human eyes and brain can distinguish . Unsaturated colors such as pink, or purple variations such as magenta, are absent, for example, because they can be made only by a mix of multiple wavelengths . Colors containing only one wavelength are also called pure colors or spectral colors . </P>

What is the approximate wavelength range for visible light