Fig. 4.

(a) Correction coefficients plotted as a function of age to calculate the effective vector lengths (VLs) of the protan (red curves), deutan (green curves), and tritan (blue curves) vectors (Vs) on the protan, deutan, and tritan confusion lines. Lines denote coefficients calculated from the linear and bilinear model. The coefficients for the tritan vector length are the mean of two coefficients each associated with the protan or deutan vectors. (Panel T) Original tritan vector length data (filled circles) and corrected tritan vector length data (open circles) modified by the coefficients shown in Fig. 4(a). Black and gray solid lines denote the best bilinear fits of the original and corrected tritan vector lengths, respectively.