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Glass was the first lens material used to make modern day eyeglasses. Its earliest use is documented back to the 13th century in Venice, Italy. It remained the only lens material choice for almost 600 years until the introduction of plastic lens materials in the mid 1900’s.

Glass lenses provide the best optics and clarity of vision. However, glass can be broken. Glass lenses are available in an almost limitless variety of designs, from single vision, multifocals, progressive lenses and occupational designs. These lenses must be tempered for impact resistance.

• Provide the best optics and clarity of vision
• The most scratch resistance of all
• Can be made to a very high index (1.8)

• Very heavy– much heavier than plastic
• Breakable thus can cause injury
• Uncomfortable
• Poor impact resistance as compared to high index plastic and poly




Developed  60 years ago this is the most commonly used lens material today. Plastic is available in a wide variety of lens designs, from single vision to progressive lenses. Approximately 50% lighter than glass, it is far less scratch resistant than glass and often must be coated to improve its scratch resistant characteristics.


• Lighter than glass
• Readily tintable
• Less likely to fog
• Low coat


• Susceptible to scratches (correctable by coating)
• Lower index of refraction makes it less suitable for higher-powered prescriptions



Polycarbonate was the original high index lens material and was introduced in 1983. It provided the ability to make thinner and lighter lenses. It has great impact resistance, but poor optical qualities as compared to newer technological breakthroughs, such as high index polyurethane plastic.

Polycarbonate is lighter than normal plastic. It has a less tendency to irritate your nose or leave red marks on your nose where the glasses touch your nose. Polycarbonate also blocks UVA and UVB rays, is shatter resistant and is used in sport glasses and glasses for children and teenagers. Because polycarbonate is soft and will scratch easily, scratch resistant coating is typically applied.  Along with trivex and hi index, polycarbonate is an excellent choice for rimless eyeglasses.

• Lighter and thinner than plastic or glass
• Highly impact resistant
• UVA and UVB protection

• Poor optical qualities
• More lens distortion than glass, plastic or hi index
• Susceptible to stress fractures in drill mounts
• Less scratch resistant than other hi index lenses
• Does not readily accept tint



Trivex is a relative newcomer that possesses the UV blocking properties and shatter resistance of polycarbonate while at the same time offers far superior optical quality. However, it may have a slightly thicker lens than polycarbonate. Along with poly and the various hi-index, trivex is a lab favorite for use in drill frames, due to the ease with which it can be drilled as well as its resistance to cracking around the drill holes. Another advantage that trivex has over polycarbonate is that it can be easily tinted.

• Highly impact resistant
• UV protection
• Excellent choice for drill mounts

• Lens availability is limited
• Slightly higher in cost than poly


HI INDEX (1.60, 1.67, 1.70 & 1.74)


Hi index typically refers to products with an index higher than 1.58 and has become a catchall phrase encompassing 1.60, 1.67, 1.70 and 1.74 index lenses. While all lenses have some curvature, high index lenses require flatter curves than plastic and polycarbonate, resulting in thinner and lighter lenses. Most lens manufactures recommend an anti-reflective coating for these lenses to reduce internal and external reflections.

Furthermore, these are readily available in aspheric lenses. Aspheric lenses reduce spatial distortion, reduce magnification and further help maintain a thin and flat lens profile. While not necessarily lighter in weight, they offer the thinnest lens profiles and are available in a variety of lens designs.


• Superior optical qualities
• Thinner computer-designed lenses eliminate distortion
• Greatly enhanced cosmetic appearance
• Lighter weight for unsurpassed comfort
• Better scratch resistance than polycarbonate
• Impact resistance is five times that of conventional plastic or glass


• Susceptible to backside and inner surface reflections (correctable with AR coating)
• Easier to scratch than glass
• Slightly higher cost than polycarbonates
• Impact resistance is slightly less than polycarbonate