Lens Materials

Plastic (CR-39):

An extremely common lens type that is a safe and reliable alternative to glass lenses is plastic CR-39. Columbian Resin #39 is a plastic polymer that was introduced in the 1950’s. Plastic lenses transmit visible light and absorb ultraviolet light better then glass lenses, making plastic the preferred choice by optometrists. Due to the physical properties of plastic lenses they can provide a greater index of refraction that allows these lenses to correct a multitude of vision irregularities.



Polycarbonate lenses are arguably the #1 recommended lenses by optometrists and opticians practicing today. These lenses are often 20% thinner and lighter than plastic CR-39 lenses and have far better optical properties. This lens is a necessity for children’s glasses and for any individual that lives an active lifestyle because polycarbonate lenses are extremely impact resistant.


Therefore these lenses are recommended to people with very strong prescriptions, sports players, kids, anyone who wants something light weight and all individuals who are safety conscious. With built in UV protection and basic scratch protection, this lens is recommended to almost all individuals.


High Index:

High Index lenses are a special type of lens that is typically used for stronger prescriptions in order to minimize the thickness of the lens. With non-high index lenses, the stronger the prescription, the thicker the lens needs to be in order to refract visible light into the eye. High index lenses feature a higher index of refraction so that light can have increased refraction with out increased thickness lens material. The index of glass lenses is 1.52 while the index for plastic lenses is 1.50. 


High index lenses are available in various indexes from 1.53 to 1.74 thus allowing for high prescriptions with thin lenses. The thinner the material the lighter the lens and this is a must have for anyone with a strong prescription. Overall these lenses are great for strong prescriptions, they are durable and cosmetically more acceptable. Say goodbye to heavy lenses that magnify your eyes and say hello to high index!


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