The nature of mensurations, terminologies and the importance of their uses are commented regarding numerical systems, logarithmic representations, units (with applications to measurements of the index of refraction, visual acuity and angles), orders of magnitude, scales, sensitivity, instrumental readings and interpolations, significant digits, precision and accuracy, reliability and significance (clinical and statistical).
Visual acuity; Refraction, ocular; Measures; Mathematics; Visual tests; Reproducibility of results; Models, theoretical