With computers, smartphones and contact lenses now essential to modern life, many — one out of every 10 Japanese people — suffer dry eye disease.
The tear film performs various functions, including maintaining a smooth surface for light refraction, lubricating the cornea and conjunctiva, and supplying the cornea with oxygen and nutrients. Many might think tears are merely water, but actually the tear film is composed of three basic layers: mucin, water and lipids, the latter of which helps prevent water evaporation from the ocular surface and protects against infection.
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