Eyeglass Lenses Advantages and Problems

High-index Thinnest and lightest most attractive plastic and comfortable for strong prescrip- 

Glass The most scratch-resistant causes the least distortion of vision. 

Thickest of all lenses not as scratch-resistant and abrasion-resistant as glass doesn t block all ultraviolet light. 

Less shatter-resistant than allyl resin plastic may cause distortion of peripheral vision, especially in strong prescriptions highly susceptible to scratches and abrasions unless specially coated most expensive. 

Can blur and cause color fringes on peripheral vision images, especially in strong prescriptions not available in some styles, including some progressive bifocals can be damaged by solvents like nail polish remover or dry-cleaning fluid. 

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