Editing Violet (color) (section)

===Optics===
[[File:Linear visible spectrum.svg|center|400px]]
Violet is at one end of the [[Visible spectrum|spectrum of visible light]], between [[blue]] light, which has a longer wavelength, and [[ultraviolet]] light, which has a shorter wavelength and is not visible to humans. Violet wavelengths are between approximately 380 and 435 nanometers. The color violet appears dark because the S cones, which contribute very little to the perception of lightness, do not have a high sensitivity to violet light. The reason why to (typical [[trichromacy|trichromat]]) humans violet light appears slightly reddish compared to spectral blue (despite spectral red being at the other end of the visible spectrum) is, according to the [[opponent process|opponent process hypothesis of color vision]], that the S-[[cone cell|cone]] type (i.e. the one most sensitive to short wavelengths) contributes some red to the red-versus-green opponent channel (which at the longer blue wavelengths gets counteracted by the M-cone type).<ref name="Machado2009">{{citation | last1 = Machado | first1 = G.M. | last2 = Oliveira | first2 = M.M. | last3 = Fernandes | first3 = L. | title = A Physiologically-based Model for Simulation of Color Vision Deficiency | journal = IEEE Transactions on Visualization and Computer Graphics | publisher = Institute of Electrical and Electronics Engineers (IEEE) | date = November 2009 | volume = 15 | issue = 6 | pages = 1291–1298 | issn = 1077-2626 | doi = 10.1109/TVCG.2009.113 | pmid = 19834201 | hdl = 10183/27630 | s2cid = 6200253 | url = https://www.inf.ufrgs.br/~oliveira/pubs_files/CVD_Simulation/CVD_Simulation.html| hdl-access = free }} Figure 2 shows S-cones contributing +0.40 to the "r − g" opponent channel.</ref> Computer and television screens, using the [[RGB color model]], cannot produce spectral violet light and instead they combine blue light at high intensity with red light at less intensity.

Monochromatic lamps emitting spectral-violet wavelengths can be roughly approximated by the color named electric violet, which is a composed-light violet producing a similar effect to the human eye.{{Citation needed|date=September 2023}}