trifocal lens /trīfō″kəl/ [Gk, treis, three; L, focus, hearth, lens, lentil] , an eyeglass lens ground with three foci to allow correction of near, intermediate, and far vision.
trifocal lens
trifocal lens /trīfō″kəl/ [Gk, treis, three; L, focus, hearth, lens, lentil] , an eyeglass lens ground with three foci to allow correction of near, intermediate, and far vision.