Universal human visual pigment curves from psychophysical data

A universal spectral absorption curve for visual pigments was used to estimate, first, the visual pigment spectra corresponding to both the photopic psychophysical data of Smith and Pokorny and the scotopic CIE V'λ, and, second, the maximum effective optical density of the visual pigments in each photoreceptor of the “averaged human observer.” These were used to determine improved corrections for light losses in the eye of that averaged observer. The same revised correction held for both long‐wavelength‐ and middle‐wave‐length‐sensitive cones, a different correction was necessary for short‐wavelength‐sensitive cones. To demonstrate the method, the sensitivity spectrum at the cornea for an assumed anomalous middle‐wavelength‐sensitive cone was calculated from these revisions.