Definition of diopter
: a unit of measurement of the refractive power of lenses equal to the reciprocal of the focal length in meters
Recent Examples of diopter from the Web
Monoyer invented the diopter, a unit of measurement that determines the distance someone must be from a text to read it.
Perhaps the glasses’ increasing diopters told a narrative.
These example sentences are selected automatically from various online news sources to reflect current usage of the word 'diopter.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.
Medical Definition of diopter
: a unit of measurement of the refractive power of a lens equal to the reciprocal of the focal length in meters
Learn More about diopter
Britannica.com: Encyclopedia article about diopter
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