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(daɪˈɒptə) or


(Units) a unit for measuring the refractive power of a lens: the reciprocal of the focal length of the lens expressed in metres
[C16: from Latin dioptra optical instrument, from Greek, from dia- through + opsesthai to see]
diˈoptral adj
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.dioptre - a unit of measurement of the refractive power of a lens which is equal to the reciprocal of the focal length measured in meters; used by oculists
unit, unit of measurement - any division of quantity accepted as a standard of measurement or exchange; "the dollar is the United States unit of currency"; "a unit of wheat is a bushel"; "change per unit volume"


, (US) diopter
nDioptrie f


, dioptre
n. dioptría, unidad de medida de refracción de un lente.
References in periodicals archive ?
Scription technology, with accuracy to the nearest 1/100 dioptre.
A rubber-coated body and eyecups, centre focusing wheel, dioptre adjustment, carry case, straps and cleaning cloth complete the finishing touches to a truly quality piece of equipment.
6 Availability Of Spherical Equivalent Dioptre Range : Plus 5 Diopter To Plus 34 Diopter.