Abstract

Whiteness is an important colorimetric characteristic for surface colors. The CIE whiteness formula, the most widely used formula, only characterizes the whiteness of a surface color under CIE standard D65 and requires a sample to be within a small chromaticity region. In this study, 20 observers evaluated the whiteness appearance of 88 samples under four light settings at different CCT levels (i.e., 3000, 4000, 5000, and 6500 K). The 88 samples were carefully selected and the spectral power distributions of the light settings were carefully designed using a spectrally tunable LED device, so that the chromaticities of the samples under each light settings uniformly covered a wide range along the yellow/blue direction in a color space, which had never been realized before. The results, together with the two recent studies, allowed the derivation of ellipsoids for classifying the whiteness appearance for surface colors. For the samples within the derived ellipsoids, though the Uchida whiteness formula with CAT02 (WUchida,CAT02) had a higher correlation to the perceived whiteness than the CIE whiteness formula with CAT02 (WCIE,CAT02), samples that were perceived as white and had a high chroma with a hue angle of blue due to the high violet/ultraviolet radiation in the illumination may had a negative WUchida,CAT02 value. A comprehensive whiteness formula that can accurately characterize the whiteness appearance for surface colors under an arbitrary light source by considering different conditions is still necessary and the work is undergoing.

© 2017 Optical Society of America

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References

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    [PubMed]
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    [PubMed]

2017 (3)

2015 (2)

M. Wei, K. W. Houser, A. David, and M. R. Krames, “Perceptual responses to LED illumination with color rendering indices of 85 and 97,” Light. Res. Technol. 47, 810–827 (2015).

K. A. Smet, G. Deconinck, and P. Hanselaer, “Chromaticity of unique white in illumination mode,” Opt. Express 23(10), 12488–12495 (2015).
[PubMed]

2014 (1)

K. W. Houser, M. Wei, A. David, and M. R. Krames, “Whiteness perception under LED illumination,” Leukos 10, 165–180 (2014).

2013 (2)

2012 (2)

M. Wei and K. W. Houser, “Status of solid-state lighting based on entries to the 2010 US DOE Next Generation Luminaire competition,” Leukos 8, 237–259 (2012).

J. Lin, R. Shamey, and D. Hinks, “Factors affecting the whiteness of optically brightened material,” J. Opt. Soc. Am. A 29(11), 2289–2299 (2012).
[PubMed]

2007 (1)

2006 (1)

M. R. Luo, G. Cui, and C. Li, “Uniform color spaces based on CIECAM02 color appearance model,” Color Res. Appl. 31, 320–330 (2006).

1998 (1)

H. Uchida, “A new whiteness formula,” Color Res. Appl. 23, 202–209 (1998).

1987 (1)

H. Uchida and T. Fukuda, “Estimation of whiteness of fluorescent whitened objects,” J. Color Sci. Assoc. Jpn. 11, 113–120 (1987).

1986 (1)

M. Cheung and B. Rigg, “Color-difference ellipsoids for five CIE color centers,” Color Res. Appl. 11, 185–195 (1986).

1979 (1)

1976 (1)

1971 (1)

E. Ganz, “Whiteness measurement,” J. Color Appearance 1, 33–41 (1971).

1936 (1)

D. B. Judd, “A method for determining whiteness of paper II,” Paper Trade Journal 103, 38–44 (1936).

1935 (1)

D. B. Judd, “A method for determining whiteness of paper,” Paper Trade Journal 100, 40–42 (1935).

Chen, S.

M. Wei and S. Chen, “Impact of spectral power distribution of daylight simulators on whiteness specification for surface colors,” Color Res. Appl.in press.

Cheung, M.

M. Cheung and B. Rigg, “Color-difference ellipsoids for five CIE color centers,” Color Res. Appl. 11, 185–195 (1986).

Cui, G.

P. A. García, R. Huertas, M. Melgosa, and G. Cui, “Measurement of the relationship between perceived and computed color differences,” J. Opt. Soc. Am. A 24(7), 1823–1829 (2007).
[PubMed]

M. R. Luo, G. Cui, and C. Li, “Uniform color spaces based on CIECAM02 color appearance model,” Color Res. Appl. 31, 320–330 (2006).

David, A.

M. Wei, K. W. Houser, A. David, and M. R. Krames, “Perceptual responses to LED illumination with color rendering indices of 85 and 97,” Light. Res. Technol. 47, 810–827 (2015).

K. W. Houser, M. Wei, A. David, and M. R. Krames, “Whiteness perception under LED illumination,” Leukos 10, 165–180 (2014).

A. David, M. R. Krames, and K. W. Houser, “Whiteness metric for light sources of arbitrary color temperatures: proposal and application to light-emitting-diodes,” Opt. Express 21(14), 16702–16715 (2013).
[PubMed]

M. Wei, K. W. Houser, A. David, and M. R. Krames, “Blue-pumped White LEDs Fail to Render Whiteness,” in Proceedings of CIE 2014 Lighting Quality & Energy Efficiency, (2014), 150–159.

Deconinck, G.

Freyssinier, J. P.

M. S. Rea and J. P. Freyssinier, “White lighting,” Color Res. Appl. 38, 82–92 (2013).

Fukuda, T.

H. Uchida and T. Fukuda, “Estimation of whiteness of fluorescent whitened objects,” J. Color Sci. Assoc. Jpn. 11, 113–120 (1987).

Ganz, E.

García, P. A.

Hanselaer, P.

Hinks, D.

Houser, K. W.

M. Wei, K. W. Houser, A. David, and M. R. Krames, “Perceptual responses to LED illumination with color rendering indices of 85 and 97,” Light. Res. Technol. 47, 810–827 (2015).

K. W. Houser, M. Wei, A. David, and M. R. Krames, “Whiteness perception under LED illumination,” Leukos 10, 165–180 (2014).

A. David, M. R. Krames, and K. W. Houser, “Whiteness metric for light sources of arbitrary color temperatures: proposal and application to light-emitting-diodes,” Opt. Express 21(14), 16702–16715 (2013).
[PubMed]

M. Wei and K. W. Houser, “Status of solid-state lighting based on entries to the 2010 US DOE Next Generation Luminaire competition,” Leukos 8, 237–259 (2012).

M. Wei, K. W. Houser, A. David, and M. R. Krames, “Blue-pumped White LEDs Fail to Render Whiteness,” in Proceedings of CIE 2014 Lighting Quality & Energy Efficiency, (2014), 150–159.

Huertas, R.

Judd, D. B.

D. B. Judd, “A method for determining whiteness of paper II,” Paper Trade Journal 103, 38–44 (1936).

D. B. Judd, “A method for determining whiteness of paper,” Paper Trade Journal 100, 40–42 (1935).

Krames, M. R.

M. Wei, K. W. Houser, A. David, and M. R. Krames, “Perceptual responses to LED illumination with color rendering indices of 85 and 97,” Light. Res. Technol. 47, 810–827 (2015).

K. W. Houser, M. Wei, A. David, and M. R. Krames, “Whiteness perception under LED illumination,” Leukos 10, 165–180 (2014).

A. David, M. R. Krames, and K. W. Houser, “Whiteness metric for light sources of arbitrary color temperatures: proposal and application to light-emitting-diodes,” Opt. Express 21(14), 16702–16715 (2013).
[PubMed]

M. Wei, K. W. Houser, A. David, and M. R. Krames, “Blue-pumped White LEDs Fail to Render Whiteness,” in Proceedings of CIE 2014 Lighting Quality & Energy Efficiency, (2014), 150–159.

Li, C.

M. R. Luo, G. Cui, and C. Li, “Uniform color spaces based on CIECAM02 color appearance model,” Color Res. Appl. 31, 320–330 (2006).

Lin, J.

Lin, Y.

W. Xu, M. Wei, A. K. G. Smet, and Y. Lin, “The prediction of perceived color differences by color fidelity metrics,” Light. Res. Technol.in press.

Luo, M.

M. Wei, S. Ma, and M. Luo, “The necessity of a whiteness scale for FWA-enhanced whites,” in Proceedings of 24th Color and Imaging Conference (2016), pp. 237–241.

Luo, M. R.

Ma, S.

M. Wei, S. Ma, Y. Wang, and M. R. Luo, “Evaluation of whiteness formulas for FWA and non-FWA whites,” J. Opt. Soc. Am. A 34(4), 640–647 (2017).
[PubMed]

M. Wei, S. Ma, and M. Luo, “The necessity of a whiteness scale for FWA-enhanced whites,” in Proceedings of 24th Color and Imaging Conference (2016), pp. 237–241.

Melgosa, M.

Noel, M.

J. C. Zwinkels and M. Noel, “CIE whiteness assessment of papers: impact of LED illumination,” in Proceedings of the 27th Session of the CIE (2011), pp. 323–330.

Pechova, M.

M. Vik, M. Vikova, and M. Pechova, “Evaluation of whiteness in case of highly tinted white materials,” in Proceedings of Asia and Africa Science Platform Program Seminar Series 10 (2017).

Rea, M. S.

M. S. Rea and J. P. Freyssinier, “White lighting,” Color Res. Appl. 38, 82–92 (2013).

Rigg, B.

M. Cheung and B. Rigg, “Color-difference ellipsoids for five CIE color centers,” Color Res. Appl. 11, 185–195 (1986).

Shamey, R.

Smet, A. K. G.

W. Xu, M. Wei, A. K. G. Smet, and Y. Lin, “The prediction of perceived color differences by color fidelity metrics,” Light. Res. Technol.in press.

Smet, K. A.

Smet, K. A. G.

Uchida, H.

H. Uchida, “A new whiteness formula,” Color Res. Appl. 23, 202–209 (1998).

H. Uchida and T. Fukuda, “Estimation of whiteness of fluorescent whitened objects,” J. Color Sci. Assoc. Jpn. 11, 113–120 (1987).

Vik, M.

M. Vik, M. Vikova, and M. Pechova, “Evaluation of whiteness in case of highly tinted white materials,” in Proceedings of Asia and Africa Science Platform Program Seminar Series 10 (2017).

Vikova, M.

M. Vik, M. Vikova, and M. Pechova, “Evaluation of whiteness in case of highly tinted white materials,” in Proceedings of Asia and Africa Science Platform Program Seminar Series 10 (2017).

Wang, Y.

Wei, M.

M. Wei, S. Ma, Y. Wang, and M. R. Luo, “Evaluation of whiteness formulas for FWA and non-FWA whites,” J. Opt. Soc. Am. A 34(4), 640–647 (2017).
[PubMed]

M. Wei, K. W. Houser, A. David, and M. R. Krames, “Perceptual responses to LED illumination with color rendering indices of 85 and 97,” Light. Res. Technol. 47, 810–827 (2015).

K. W. Houser, M. Wei, A. David, and M. R. Krames, “Whiteness perception under LED illumination,” Leukos 10, 165–180 (2014).

M. Wei and K. W. Houser, “Status of solid-state lighting based on entries to the 2010 US DOE Next Generation Luminaire competition,” Leukos 8, 237–259 (2012).

M. Wei, S. Ma, and M. Luo, “The necessity of a whiteness scale for FWA-enhanced whites,” in Proceedings of 24th Color and Imaging Conference (2016), pp. 237–241.

W. Xu, M. Wei, A. K. G. Smet, and Y. Lin, “The prediction of perceived color differences by color fidelity metrics,” Light. Res. Technol.in press.

M. Wei and S. Chen, “Impact of spectral power distribution of daylight simulators on whiteness specification for surface colors,” Color Res. Appl.in press.

M. Wei, K. W. Houser, A. David, and M. R. Krames, “Blue-pumped White LEDs Fail to Render Whiteness,” in Proceedings of CIE 2014 Lighting Quality & Energy Efficiency, (2014), 150–159.

Xu, W.

W. Xu, M. Wei, A. K. G. Smet, and Y. Lin, “The prediction of perceived color differences by color fidelity metrics,” Light. Res. Technol.in press.

Zhai, Q.

Zwinkels, J. C.

J. C. Zwinkels and M. Noel, “CIE whiteness assessment of papers: impact of LED illumination,” in Proceedings of the 27th Session of the CIE (2011), pp. 323–330.

Appl. Opt. (2)

Color Res. Appl. (4)

M. S. Rea and J. P. Freyssinier, “White lighting,” Color Res. Appl. 38, 82–92 (2013).

H. Uchida, “A new whiteness formula,” Color Res. Appl. 23, 202–209 (1998).

M. Cheung and B. Rigg, “Color-difference ellipsoids for five CIE color centers,” Color Res. Appl. 11, 185–195 (1986).

M. R. Luo, G. Cui, and C. Li, “Uniform color spaces based on CIECAM02 color appearance model,” Color Res. Appl. 31, 320–330 (2006).

J. Color Appearance (1)

E. Ganz, “Whiteness measurement,” J. Color Appearance 1, 33–41 (1971).

J. Color Sci. Assoc. Jpn. (1)

H. Uchida and T. Fukuda, “Estimation of whiteness of fluorescent whitened objects,” J. Color Sci. Assoc. Jpn. 11, 113–120 (1987).

J. Opt. Soc. Am. A (3)

Leukos (2)

M. Wei and K. W. Houser, “Status of solid-state lighting based on entries to the 2010 US DOE Next Generation Luminaire competition,” Leukos 8, 237–259 (2012).

K. W. Houser, M. Wei, A. David, and M. R. Krames, “Whiteness perception under LED illumination,” Leukos 10, 165–180 (2014).

Light. Res. Technol. (1)

M. Wei, K. W. Houser, A. David, and M. R. Krames, “Perceptual responses to LED illumination with color rendering indices of 85 and 97,” Light. Res. Technol. 47, 810–827 (2015).

Opt. Express (4)

Paper Trade Journal (2)

D. B. Judd, “A method for determining whiteness of paper,” Paper Trade Journal 100, 40–42 (1935).

D. B. Judd, “A method for determining whiteness of paper II,” Paper Trade Journal 103, 38–44 (1936).

Other (13)

Y. J. Cho, L.C. Ou, G. Cui, and M. R. Luo, “New color appearance scales for describing saturation, vividness, blackness, and whiteness,” Color Res Appl., published online (2017).

CIE, “Colorimetry,3rd edition,” in CIE15:2004, CIE, Vienna, Austria, (2004).

ISO, “Paper and board - determination of CIE whiteness, D65/10° (outdoor daylight),” in ISO 11475:2004 (ISO, Jersey City, NJ, USA, 2004).

ISO, “Paper and board - determination of CIE whiteness, C/2° (indoor illumination conditions),” in ISO 11476:2010 (ISO, Jersey City, NJ, USA, 2004).

M. Wei, K. W. Houser, A. David, and M. R. Krames, “Blue-pumped White LEDs Fail to Render Whiteness,” in Proceedings of CIE 2014 Lighting Quality & Energy Efficiency, (2014), 150–159.

M. Wei and S. Chen, “Impact of spectral power distribution of daylight simulators on whiteness specification for surface colors,” Color Res. Appl.in press.

J. C. Zwinkels and M. Noel, “CIE whiteness assessment of papers: impact of LED illumination,” in Proceedings of the 27th Session of the CIE (2011), pp. 323–330.

S. Ma, M. Wei, J. Liang, B. Wang, Y. Chen, M. Pointer, and M. R. Luo, “Evaluation of whiteness metrics,” Lighting Res Technol., published online (2016).

M. Wei, S. Ma, and M. Luo, “The necessity of a whiteness scale for FWA-enhanced whites,” in Proceedings of 24th Color and Imaging Conference (2016), pp. 237–241.

M. Vik, M. Vikova, and M. Pechova, “Evaluation of whiteness in case of highly tinted white materials,” in Proceedings of Asia and Africa Science Platform Program Seminar Series 10 (2017).

CIE, “CIE Research Strategy” (Accessed Jun 26, 2017) http://www.cie.co.at/index.php/Research+Strategy .

W. Xu, M. Wei, A. K. G. Smet, and Y. Lin, “The prediction of perceived color differences by color fidelity metrics,” Light. Res. Technol.in press.

M. D. Fairchild, Color Appearance Models, 3rd ed. (John Wiley & Sons, 2013).

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Figures (11)

Fig. 1
Fig. 1 Illustration about how chromaticity shift introduces the change of color appearance and change of whiteness appearance.
Fig. 2
Fig. 2 Relative SPDs of the four light settings, as measured using a calibrated JETI specbos 1211TM spectroradiometer with a standard reflectance being placed at the center of the floor in the booth.
Fig. 3
Fig. 3 Distribution of the chromaticity coordinates (x,y) of the 88 samples under the 6500 K light settings at different luminance factor levels (Y), calculated using CIE 1964 CMFs. (a) the chromaticities of the 6500 K light setting, together with the 3-step and 7-step MacAdam ellipses; (b) 40<Y≤60; (c) 60<Y≤80; (d) 80<Y≤100; (e) 100<Y (the FWA samples are labelled with □; the non-FWA samples are labelled with ▲).
Fig. 4
Fig. 4 Correlation between the two evaluations—magnitude estimation (i.e., whiteness percentage) and forced choice—made by the observers
Fig. 5
Fig. 5 CAM02-UCS chroma versus hue angle, color labeled with the average whiteness percentage values evaluated by the observers, for samples under the 6500 K light setting. (a) samples outside the CIE limit and not perceived as white (n = 76); (b) samples outside the CIE limit but perceived as white (n = 107); (c) samples within the CIE limit and perceived as white (n = 165). The FWA-enhanced samples are labelled with square; the non-FWA samples are labelled with diamond.
Fig. 6
Fig. 6 CAM02-UCS chroma versus hue angle, color labeled with the average whiteness percentage values evaluated by the observers, for samples under the four levels of CCT. (a) for those that were not perceived as white; (b) for those that were perceived as white. The FWA-enhanced whites are labelled with square; the non-FWA whites are labelled with diamond. (Note: as the lightness of the samples cannot be plotted in this figure, the samples with same chroma and hue may have different lightness, causing different whiteness evaluations).
Fig. 7
Fig. 7 The chromaticity coordinates of the samples under each CCT level and the fitted ellipsoids of whiteness boundary of surface colors for each CCT level in xyY color space. Red: perceived as white; Blue: perceived as non-white. (a) xy plane; (b) xY plane. The FWA-enhanced samples are labelled with solid circles; the non-FWA samples are labelled with open circles.
Fig. 8
Fig. 8 The chromaticity coordinates of the samples and the fitted ellipses of the whiteness boundary of surface colors for different CCT levels in a’-J’ plane of CAM02-UCS. The FWA-enhanced samples are labelled with solid circles; the non-FWA samples are labelled with open circles. Red: perceived as white; Blue: perceived as non-white.
Fig. 9
Fig. 9 The chromaticity coordinates of the samples and the fitted ellipses of the whiteness boundary of surface colors for different CCT levels in a’-b’ plane of CAM02-UCS. The FWA-enhanced samples are labelled with solid circles; the non-FWA samples are labelled with open circles. Red: perceived as white; Blue: perceived as non-white.
Fig. 10
Fig. 10 Scatter plots of the perceived whiteness rated by the observers and the whiteness values calculated using the CIE whiteness formula and the Uchida whiteness formula with CAT02. Only the samples that were rated as white are plotted, with the FWA-enhanced samples being labelled in blue and non-FWA samples being labelled in red. The correlation coefficients are summarized in Table 3. Left: the CIE whiteness formula with CAT02; Right: the Uchida whiteness formula with CAT02.
Fig. 11
Fig. 11 Scatter plot of WUchida,CAT02 versus WCIE,CAT02 for the samples that were rated as white, color labeled with the average whiteness percentage values evaluated by the observers. The FWA-enhanced samples are labelled with square; the non-FWA samples are labelled with diamond.

Tables (3)

Tables Icon

Table 1 Summary of colorimetric characteristics of the four light settings

Tables Icon

Table 2 Summary of the ellipses in Fig. 9

Tables Icon

Table 3 Performance of WCIE,CAT02 and WUchida,CAT02 in terms of the correlation coefficients between the calculated and the perceived whiteness values.

Equations (7)

Equations on this page are rendered with MathJax. Learn more.

W = D Y + P x + Q y + C
W C I E = Y + 800 ( x n x ) + 1700 ( y n y )
T C I E = 1000 ( x n x ) 650 ( y n y )
T 10 , C I E = 900 ( x n , 10 x 10 ) 650 ( y n , 10 y 10 )
W U c h i d a = W C I E 2 ( T C I E ) 2
W U c h i d a = P W 2 ( T C I E ) 2
P W = ( 5 Y 275 ) { 800 [ 0.2742 + 0.00127 ( 100 Y ) x ] 0.82 1700 [ 0.2762 + 0.00176 ( 100 Y ) y ] 0.82 }

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