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Encyclopedia > Spectral color

A spectral color is a color that is evoked by the optical spectrum; every wavelength of light yields a different spectral color, in a continuous spectrum. The visible spectrum is the portion of the optical spectrum (light or electromagnetic spectrum) that is visible to the human eye. ...


The photons themselves have no color. Color is an effect created by the mind to make us aware of differences in photon wavelength.


The spectrum is often divided up into named colors, though any division is somewhat arbitrary: the spectrum is continuous. Traditional colors include:

  1. Red
  2. Orange
  3. Yellow
  4. Green
  5. Cyan
  6. Blue
  7. Indigo
  8. Violet

Indigo is often omitted as simply a shade of blue/violet, and cyan was not included historically. The first division was by Newton, in his color wheel, and he used Red, Orange, Yellow, Green, Blue, Indigo, Violet; a mnemonic is ROYGBIV. Red is any of a number of similar colors evoked by light consisting predominantly of the longest wavelengths of light discernible by the human eye, in the wavelength range of roughly 625–750 nm. ... See also Orange (disambiguation) for other meanings of the word. ... A yellow Tulip. ... Mossy, green fountain in Wattens, Austria. ... Cyan (from Greek κυανοs, meaning blue) may be used as the name of any of a number of a range of colors in the blue/green part of the spectrum. ... YOU SUCK!!!!! ... Indigo (or spectral indigo) is the color on the spectrum between 440 and 420 nanometres in wavelength, placing it between blue and violet. ... Violet (named after the flower violet) is used in two senses: first, referring to the color of light at the short-wavelength end of the visible spectrum, approximately 380–420 nanometres (this is a spectral color). ... Sir Isaac Newton, (4 January 1643 – 31 March 1727) [ OS: 25 December 1642 – 20 March 1727][1] was an English physicist, mathematician, astronomer, natural philosopher, and alchemist, regarded by many as the greatest figure in the history of science. ... In the arts of painting, graphic design, and photography, color theory is a body of practical guidance to color mixing and the visual impact of specific color combinations. ... Wikiquote has a collection of quotations related to: English mnemonics A mnemonic (pronounced in RP, [nɪmɑnɪk] in GA) is a memory aid, and most serve an educational purpose. ... Wikiquote has a collection of quotations by or about: English mnemonics#Colour ROYGBIV, pronounced like the name Roy G. Biv, is a popular mnemonic device used for memorizing the traditional optical spectrum, though some believe that cyan belongs between green and blue. ...


Among some of the colors that are not spectral colors are:

  • Grayscale colors, such as White, Silver, Gray, and Black
  • Any color obtained by mixing a grayscale color and a spectral color, such as brown - mixture of yellow and black obtained contrast.
  • Purple (similarly, magenta), which is a mixture of Blue and red

In the CIE xy chromaticity diagram, the spectral colors are the horseshoe shape curve on the outside. All other colors are not spectral: the bottom straight line is the line of purples, while the interior are unsaturated colors: a mixture of a spectral color and a grayscale color. This article is about the color. ... Silver is the metallic shade of the color gray closest to that of polished silver. ... Gray or grey is a color seen commonly in nature. ... Black cat, thought by some to cause bad luck Black is the shade of objects that do not reflect light in any part of the visible spectrum. ... Brown, when used as a general term, is a color which is a dark orange, red or rose, of very low intensity. ... An African Daisy of almost psychedelic purple Purple is any shades of color occurring between blue and red; this color is sometimes confused with the more narrowly-defined spectral color violet. ... Magenta is a color made up of equal parts of red and blue light. ... Blue (from Old High German blao shining) is one of the three primary additive colors; blue light has the shortest wavelength (about 470 nm) of the three primary colors. ... Red is any of a number of similar colors evoked by light consisting predominantly of the longest wavelengths of light discernible by the human eye, in the wavelength range of roughly 625–750 nm. ... In the study of the perception of color, one of the first mathematically defined color spaces was the CIE XYZ color space (also known as CIE 1931 color space), created by the International Commission on Illumination (CIE) in 1931. ...


The visible spectrum as a combination of spectral colors

Visible light is a blend of (normally) all spectral colors, leading to a common understanding of visible light as "white"; however, depending upon the specific light source, the relative intensity of each color varies. This phenomenon explains why there exists a tinge of color perceived in certain light sources themselves. For example, high pressure sodium and some fluorescent sources have an off-white color. This phenomenon is important in evaluating the effects of light upon humans from light sources that are not matched well to the specrum of natural sunlight. The study of these health effects is dealt with in the field of over-illumination. A sodium vapor lamp is a gas discharge lamp which uses sodium in an excited state to produce light. ... Fluorescence induced by exposure to ultraviolet light in vials containing various sized cadmium selenide (CdSe) quantum dots. ... Prism splitting light High Resolution Solar Spectrum Sunlight in the broad sense is the total spectrum of the electromagnetic radiation given off by the Sun. ... This cosmetics store has lighting levels over twice recommended levels and sufficient to trigger headaches and other health effects Over-illumination is the presence of lighting intensity (illuminance) beyond that required for a specified activity. ...


  Results from FactBites:
 
Color (361 words)
In a rainbow or the separation of colors by a prism we see the continuous range of spectral colors (the visible spectrum).
This works well for spectral colors but it is found that many different combinations of light wavelengths can produce the same perception of color.
The inherently distinguishable characteristics of color are hue, saturation, and brightness.
Color - MSN Encarta (1019 words)
Color, physical phenomenon of light or visual perception associated with the various wavelengths in the visible portion of the electromagnetic spectrum (see Electromagnetic Radiation; Spectrum).
The color of light of a single wavelength or of a small band of wavelengths is known as a pure spectral color or hue.
An example of the mixing of subtractive primaries is in color photography and in the printing of colored pictures in magazines, where magenta, yellow, fl, and cyan inks are used successively to create natural color.
  More results at FactBites »

 
 

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