[Spectral sensitivities on monochromatic backgrounds]

The spectral sensitivities of cone mechanisms were measured on monochromatic backgrounds and the results were compared with the Stiles II-mechanism. Narrow band interference filters with dominant wavelengths of 430 nm and 700 nm were used for background light. The pattern of the spectral sensitivity curve on a 430 nm background with a retinal illuminance of 530 photopic trolands was similar to that of the Stiles II 5-mechanism (long wavelength-sensitive cones). The pattern of the spectral sensitivity curve on a 700 nm background with a retinal illuminance of 530 photopic trolands showed two peaks. The peak in the short wavelength region coincided with that of the short wavelength-sensitive cones and the peak in the middle and long wavelength regions coincided with the Stiles II 4-mechanism (middle wavelength-sensitive cones). As a result, it was suggested that this method is useful to investigate color information processing in both normal and color-defective observers.