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Color and Light · entry 33 of 52
Purple and violet describe similar hues, though violet refers to a single wavelength of light.
The longer version
Violet is a spectral color: a single wavelength near the short end of the visible range, produced directly by light itself. Purple has no wavelength of its own. It appears only when red and blue cone signals are stimulated together, a mixture the visual system invents rather than measures.
That is why purple can be made on a screen by combining red and blue light, while violet cannot be synthesized the same way. The distinction matters in printing, where a violet ink and a purple ink behave differently under changing illumination. Most people use the words interchangeably, and the boundary between them is learned, not physical.
Where this entry sits
These facts explore how light behaves and how human eyes turn it into the colors we see. Along the way you meet rainbows, prisms, mirrors, shadows, lasers, and optical tricks that fool our vision every day. The full list sits on the Color and Light page, where every entry is listed in order.
More From Color and Light
Eight more entriesMany languages have fewer basic color words than English, sometimes grouping blue and green together.
Read 35Turquoise sits between blue and green on the spectrum and is named after a gemstone.
Read 36Gold and silver describe metallic surface appearances rather than one particular wavelength of light.
Read 37The color of a flame changes with temperature, shifting from red toward blue as it gets hotter.
Read 38Optical illusions trick the brain by exploiting the shortcuts it uses to interpret light and edges.
Read 39Afterimages appear when staring at a bright color fatigues the cone cells responding to that hue.
Read 40A gray square looks lighter on a black background than the same square on a white one.
Read 41Neon colors seem to glow because they reflect more light than ordinary dyes can.
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