Abstract
IT has been recognized that, in the scotopic range, the spectral sensitivity of static pupil size demonstrates a curve similar to the CIE scotopic efficiency curve, and as does the pupil's dynamic threshold (1-2). On the other hand, in eyes adapted to light, Bouma measured the spectral energy from 425 to 660 nm, that evoked a 4 to 5 mm pupil contraction, and depicted that pupillary spectral sensitivity is enhanced in the blue wavelength region with a peak at 490 nm, a result quite different from the CIE photopic visibility function (3). To determine whether a blue-cone mediated contribution in the pupillary light reflex pathway is more dominant than in the luminance channel to the visual cortex, it will be of importance to re-investigate the static and dynamic pupillary behaviors in photopic, mesopic, and scotopic ranges.