Fig. 6.

Protan (P), deutan (D), and tritan (T) vector lengths for protanomalous and deuteranomalous subjects as a function of age. The filled triangles and open squares represent the protanomalous and deuteranomalous subjects, respectively. The solid lines are the normal mean, with dotted and dashed functions representing +1 and +2 SDs (as in Fig. 3). The thick solid horizontal lines represent the thresholds for each vector, as given by the developers of the CCT. For cases in which the protan or deutan vector measurement was not possible, the vector length was set as 1100 (four deuteranomalous subjects’ data points were plotted at 1080 or 1050 for clarity in the plot). Data points enclosed by a gray circle denote the deuteranomalous observer (discussed in the text).