This article is from the Vision and Eye Care FAQ, by grants@research.canon.com.au (Grant Sayer) with numerous contributions by others.
Spectacle lenses, depending on the type of material will absorb varying
amounts of ultraviolet light. In order of best absorbing lens the materials
are polycarbonate, plastic and finally glass lenses. Different standards
define the amount of absorption required, and/or the definition of the
categories for spectacle lenses. The amount of UV absorption is also
influenced by tinting, dying and lens coatings.
 
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