chromaticity coordinates


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chromaticity coordinates

[‚krō·mə′tis·əd·ē kō′ȯrd·ən‚āts]
(optics)
The fractional amounts of the x, y, and z primary colors, specified by the International Committee on Illumination, in a color sample; more precisely, x = X /(X + Y + Z), y = Y /(X + Y + Z), z = Z /(X + Y + Z), where X, Y, and Z are the integrals over wavelength λ of the product of the amount of light emerging from the sample per unit wavelength, and the tristimulus values, (λ), (λ), and (λ), respectively.
References in periodicals archive ?
The chromaticity coordinates (r, g, b) is the cross point between vector signals (R, G, B) and r + g + b = 1, as shown in Fig.
The chromaticity coordinates x, y, and z have been developed and established by the Commission International de 1'Eclairage (CIE).
The CIE (Commission Internationale de I'Eclairage, 1931) chromaticity coordinates of GdV[O.sub.4]:[Sm.sup.3+] are presented in Figure 9.
(v) Conversion of XYZ tristimulus values to the (x, y) chromaticity coordinates and the relation to the FUI values, where x = X/(X + Y + Z) and y = Y/(X + Y + Z) defines the (x, y) chromaticity coordinates
where [L.sub.f], [a.sub.f], and [b.sub.f] are the lightness and chromaticity coordinates after the UV exposure, respectively, and [L.sub.i] [a.sub.i], and [b.sub.i] are the lightness and chromaticity coordinates before the UV exposure, respectively.
The samples were evaluated for luminosity from zero (black) to 100 (white), chromaticity coordinate [a.sup.*], whose negative value represents tendency to the green color and positive value, a tendency to the red color, and chromaticity coordinate [b.sup.*], whose negative value shows tendency to the blue color and positive value to the yellow color.
The changes of chromaticity coordinates ([a.sup.*] and [b.sup.*]) were quiet different among WPCs as shown in Figs.
And, suffice it to say, different spectral power distributions with the same luminance and correlated color temperature (even with identical chromaticity coordinates) can produce different experiences along the dimensions of brilliance and colorfulness.
The simulation program can predict not only the relative SPD, chromaticity coordinates, but also numbers of LED (N), drive currents ([I.sub.F]), the input power ([P.sub.in]), the luminous flux ([PHI]), and the luminous efficacy ([eta]) according to requirements of CRI, R9, CCT, and the distance from the Planckian locus on the CIE 1960 uv chromaticity diagram (dC), with polarity, plus (above the Planckian locus) or minus (below the Planckian locus) [15].
The chromaticity coordinates of the ZnO:YAG films at 1, 5, and 10wt% on Si substrate are presented in the CIE chromaticity diagram, as shown in Figure 6.
As illustrated in Figure 5, the emission color of CaFBr:[Eu.sup.3+] phosphor can be expressed by the Commission International de l'Eclairage (CIE) chromaticity coordinates. The prepared CaFBr:[Eu.sup.3+] phosphor exhibits red light, and its chromaticity coordinate is x = 0.65, y = 0.32.
The spectrometer transformed spectral data into lightness data (L) and chromaticity coordinates (redness [a] and yellowness [b]) on the basis of a D65 light source (CIE 1986).