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A unified formula for light-adapted pupil size  (2012)
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The size of the pupil has a large effect on visual function, and pupil size depends mainly on the adapting luminance, modulated by other factors. Over the last century, a number of formulas have been proposed to describe this dependence. Here we review seven published formulas and develop a new unified formula that incorporates the effects of luminance, size of the adapting field, age of the observer, and whether one or both eyes are adapted. We provide interactive demonstrations and software implementations of the unified formula.
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adaptation, age, contrast, diameter, function, illuminance, light, miosis, pupil, reflex, retinal, senile, sensitivity
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Journal of Vision (2012) 12(10):12, 1-16
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Adobe PDF Icon  watson_formula_pupilsize.pdf (Download Acrobat Reader Click to download Adobe Acrabat Reader)
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Curator: Phil So
NASA Official: Alonso Vera
Last Updated: August 15, 2019