Flat Hi.ank … ToRic Blank KRYPTOKS are made of two jiieoes of optical ^lass of different substanceand hence of different foci, or strenoth, fused into a sino;le pieceof olass and oTountl as a sino-le lens.They differ from tlie cemented l>ifocal in that they have no distinct hue ofdemarcation between the…
Lenses · Eyeglasses
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