acing cylinder side, rotate the lens 5° for eachmillimeter it is to be set in. If lens is for Right eye, rotate disc toward left. If lens is for Left eye, rotate disc toward right. Then mark the axis on the side upon which the cylinder surface is to beground in the usual manner, using protractor.… … ULTEX Onepiece Bifocal Lenses show no marked line of separationbetween the distance and reading portions. They are single, solidlenses, althou<rh ground with two foci. Being of a single piece ofglass, they are free from disturl)ing color effects. Every Ultex bifocal lens of our manufacture has…
Lenses · Eyeglasses
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