Pupillary Distance Measurement
In the most common sense, a Pupilometer is a tool for measuring pupillary distance (PD). It is used for fitting eyeglasses so that the lenses are centered in the visual axis. This is the most common nomenclature. It may also be used to verify a PD measurement taken from a millimeter ruler placed across the bridge of a patient's nose for distance and near focus.
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Famous quotes containing the words distance and/or measurement:
“I do believe that the outward and the inward life correspond; that if any should succeed to live a higher life, others would not know of it; that difference and distance are one. To set about living a true life is to go on a journey to a distant country, gradually to find ourselves surrounded by new scenes and men; and as long as the old are around me, I know that I am not in any true sense living a new or a better life.”
—Henry David Thoreau (1817–1862)
“That’s the great danger of sectarian opinions, they always accept the formulas of past events as useful for the measurement of future events and they never are, if you have high standards of accuracy.”
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