astigmatic difference

astigmatic difference

[¦a·stig‚mad·ik ′dif·rəns]
(optics)
The distance between the primary and secondary foci of an astigmatic optical system.
The difference between the reciprocals of the distances of the primary and secondary foci from an astigmatic thin lens or mirror.
References in periodicals archive ?
Naylor, "Astigmatic difference in refractive errors," British Journal of Ophthalmology, vol.