Abstract

The color of a material, such as solution of a dye, can change by changing parameters like pH, temperature, illumination direction, and illumination type. Dichromatism—a color change due to the difference in thickness of the material—has long been known as a property of only a few materials. Here we show that dichromatism is a common property of many substances and materials, and we introduce a method for its quantification. We defined dichromaticity index (DI) as the difference in hue angle $\left(\Delta h_{ab}\right)$ between the color of the sample at the dilution, where the chroma is maximal, and the color of four times more diluted (or thinner) and four times more concentrated (or thicker) sample. The two hue angle differences are called dichromaticity index toward lighter $\left({\mathrm{DI}}_{\mathrm{L}}\right)$ and dichromaticity index toward darker $\left({\mathrm{DI}}_{\mathrm{D}}\right)$, respectively. High dichromaticity was found for materials that were previously known as dichromatic (pumpkin oil, bromophenol).

© 2009 Optical Society of America

Computerized simulation of color appearance for dichromats

Hans Brettel, Françoise Viénot, and John D. Mollon
J. Opt. Soc. Am. A 14(10) 2647-2655 (1997)

Color constancy for daylight illumination changes in anomalous trichromats and dichromats

Stacey Aston, Gabriele Jordan, and Anya Hurlbert
J. Opt. Soc. Am. A 40(3) A230-A240 (2023)

Evolutionary models of color categorization. I. Population categorization systems based on normal and dichromat observers

Kimberly A. Jameson and Natalia L. Komarova
J. Opt. Soc. Am. A 26(6) 1414-1423 (2009)

Color rendering of art paintings under CIE illuminants for normal and color deficient observers

João Manuel Maciel Linhares, Paulo Daniel Araújo Pinto, and Sérgio Miguel Cardoso Nascimento
J. Opt. Soc. Am. A 26(7) 1668-1677 (2009)

Corresponding-pair procedure: a new approach to simulation of dichromatic color perception

Pascual Capilla, Marı́a Amparo Dı́ez-Ajenjo, Marı́a José Luque, and Jesús Malo
J. Opt. Soc. Am. A 21(2) 176-186 (2004)