Large-field color matching functions

Color-matching functions (CMFs) were derived with the Maxwell method for 10 subjects using two field conditions: (1) horizontally bisected circular 10° and (2) vertically bisected rectangular 102° (wide) × 50° (high). The primary set was composed of 453-533-601 nm components with a mean full-width at half maximum of 18.3 nm; the reference field was illuminated with daylight fluorescent lamplight. Field size had a significant effect on the shape of the resulting CMFs. Under the large-field conditions subjects were less sensitive to shorter wavelengths as characterized with the b̄ function and had higher sensitivities to the longer wavelengths as characterized with the r̄ function.