diopter

(redirected from dioptral)
Also found in: Dictionary, Thesaurus, Encyclopedia.

diopter

 [di-op´ter]
a unit of refractive power of lenses: the reciprocal of the focal length in meters is the refractive power in diopters. Symbol D.

di·op·ter (D),

(dī-op'tĕr),
The unit of refracting power of lenses, denoting the reciprocal of the focal length expressed in meters.
[G. dioptra, a leveling instrument]

di·op·ter

(D, Δ, δ) (dī-op'tĕr)
The unit of refracting power of lenses, denoting the reciprocal of the focal length expressed in meters.
[G. dioptra, a leveling instrument]

Diopter (D)

Unit describing the amount of focusing power of a lens.