DIOPTER
diopter
Noun
- A unit of measure of the power of a lens or mirror, equal to the reciprocal of its focal length in meters. Myopia is diagnosed and measured in diopters.
- Any lens system, such as a telescope.
- A theodolite or similar surveyor’s angle measuring device.
- An alidade.
- A surgical speculum.
- An instrument for drawing the skull by projections.
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