Evaluation of the spectral power distribution of the illuminant in mesopic functional vision

Abstract

The visual response in mesopic adaptation depends strongly not only on the level of luminance but also on the
relative weight of the response of the cones and rods system. This highlights the importance of knowing the
spectral power distribution (SPD) of radiation, when evaluating the functional vision. For this reason, this work
proposes the measurement of mesopic contrast sensitivity, analyzing the impact of the SPD of the illuminant on
functional vision. In the experiment, two young subjects (25 and 30 years old) participated, with two levels of
photopic luminance adaptation (0.3 and 3 cd/m2), three spatial frequencies (1, 2 and 3 c/d), two different SPDs
one of them with a peak in the blues area (λ = 448 nm) and the other in the red area (λ = 616 nm), all of this in the
peripheral temporal zone of the retina. Differences were found between both SPDs in the interaction between
luminance and spatial frequency.