Property, Performance, and Product

There are plastics that are transparent and translucent in the unpiginented state. They have a range of optical properties that make them interesting for a wide spectrum of optical applications that extends from windows to lens systems to sophisticated applications involving action via polarized light. Used for over a half century are aircraft canopies (thermoformed) and windows in many different structures. 

The application for plastics most widely known, based on the transparency and clarity of plastics, is their use as a window or 

The ophthalmic applications for plastics lenses include contact lenses which are now made of acrylic plastics. Another material for this application is a special hydrophillic acrylic polymer used in soft contact lenses. These lenses are much more comfortable than rigid contact lenses. 

Important applicable definitions that concern this subject follows  

Refractive index is the ratio of the velocity of light in free space to the velocity of light in the medium. 

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