Contact lenses are made of ________? 

The correct answer is Silicon Hydrogel.

Key Points 

• The contact lens is a device worn in the eye to correct vision, although some people wear colored contact lenses to enhance or change their eye color.
• Silicon Hydrogel is a newer material that has become increasingly popular in recent years.
• It is a type of soft contact lens that allows more oxygen to pass through to the cornea compared to traditional hydrogel lenses.
• This increased oxygen permeability can help reduce the risk of eye infections and other complications.
• The conventional hard contact lenses were made of a hard plastic material called polymethyl methacrylate also known as Lucite. 
• Hard contact lenses are made of some variant of polymethyl methacrylate (PMMA).
• Soft contact lenses are made of a polymer such as poly hydroxyethyl methacrylate (pHEMA) that has hydrophilic qualities, that is, it can soak up water and still retain its shape and optic functions.
• The science of lens material is always being updated by lens manufacturers, and the specific material of any contact lens may differ depending on the maker.