LYCOS RETRIEVER 
Lens: Materials
built 605 days ago
In this case, since the plastic bottle isn't the same size as a typical Russky lens, the cut has to be slightly concave to make the fit perfect. When you're faced with the same problem, you make sure to cut the material properly for a perfect fit.
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Different lens materials may ... be used to minimize chromatic aberration, such as specialized coatings or lenses made from the crystal fluorite. This naturally occurring substance has the highest known Abbe number, indicating that the material has low dispersion.
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A contact lens is a medical device. If it's not properly prescribed, you may not see well. More importantly, a poorly fitting lens — or one made from a material not well-suited to your eyes — could result in discomfort, inflammation, swelling, abrasion, or another problem that could, in rare cases, result in permanent eye tissue damage.
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