Fig. 1From: Association of Photopic and Mesopic Contrast Sensitivity in older drivers with risk of motor vehicle collision using naturalistic driving dataIllustration of the contrast sensitivity function (CSF). The spatial contrast sensitivity function, defined as the reciprocal of the contrast threshold as a function of spatial frequency, can be described by four parameters: the peak contrast sensitivity, CSmax; the peak spatial frequency, SFmax; degree of curvature of the left and right branches of the asymmetric parabolic function, widthL and widthR. In addition, we can obtain a summary statistic of contrast sensitivity: area under log CSF (AULCSF) which represents the overall contrast sensitivity of the functionBack to article page