Modeling wavelengths and spectral half-power bandwidths for Rayleigh equation anomaloscopes.

The recommended and required wavelengths for Rayleigh equation anomaloscopes are many and varied and without a numerical evidence base. The requirements for spectral half-power bandwidth in the German standard DIN 6160 also have no known evidence base. This paper provides data to establish requirements. The constraint on the short-wavelength limit of green was assessed by plotting chromaticities for wavelengths around the Nagel anomaloscope green and spectral half-power bandwidths up to 60 nm and identifying the combinations that lie within the first half confusion zone from the spectral locus of the deuteranope, being more restrictive than the protanopic zone. The other wavelength limits were assessed by modeling the match point and matching range using the normal and anomalous photopigment data of J. Opt. Soc. Am. A9, 1465 (1992)JOAOD60740-323210.1364/JOSAA.9.001465. The proposed wavelength limits are expressed as chromaticity, equivalent wavelength, and spectral half-power bandwidth limits. The wavelength limits are less restrictive than in DIN 6160.