Evolution of Contact Lenses

In 1508, Leonardo da Vinci conceived the concept of the contact lens. It was not until 1887 that scleral contact lenses were fabricated by Dr. A. E. Fick, a physician in Zurich; F. A. Mueller, a maker of prosthetic eyes in Germany; and Dr. E. Kalt, a physician in France. Muller, Obrig, and Gyorry fabricated contact lenses made from polymethyl methacrylate (PMMA) in the late 1930s. K. Tuohy filed the patent for contact lens design in 1948, which were made of PMMA material (371). Although they were safe and effective, these lenses were uniformly uncomfortable, thus suppressing their potential growth for contact lens wear. Lenses made from polyhydroxyethyl methacrylate (HEMA), the so-called soft lenses or hydrophilic lenses were introduced in 1970. Since then, significant technological advances have been made in the lens materials, lens fabrication, and lens designs (372). Consequently, a phenomenal growth in lens wearers necessitated the need for, and development of, lens care products. Recent development in polymers has led to a broad acceptance of materials prepared by combining HEMA with silicone (silicone hydrogels) (373). Such materials are considered to improve oxygen permeability required to maintain healthy cornea.

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