Eyeglass lenses can be made out of many different types of materials from organic plastics to even regular old glass.
Eyeglass Lenses: What They’re Made of
The lens market has constantly changed over the years. Back in the 50’s and 60’s, Glass was the most commonly used material for lenses. Then, starting in the late 50′s and early 60’s, plastic CR-39 lenses came out and started to eat at the market share of Glass—by the mid 70’s CR-39 was the more popular, dominant material.
The only obstacle for CR-39 lenses had was the Corning Photogray Extra lenses (Glass Transition), which were very popular at the time. But then PPG developed Transition lenses back in the late 80’s, and it was all over for glass by mid-90’s: the plastic transition market took off and glass lenses were reduced to a very minimal amount of the eyeglasses market.
Currently in the market today Glass has about 2% of the market, while CR-39 still has the largest chunk of at about 40%. But in the past 10 years, Polycarbonate, High Index Lenses, and now Trivex are really picking up steam in the industry.
CR-39 is the cheapest plastic currently on the market. It has good optical quality, decent scratch resistance, and it is a lightweight product. Polycarbonate, on the other hand, has a higher index and much better impact resistance to CR-39, but the optical quality and scratch resistance is sub-par. The cost of polycarbonate is also slightly higher than CR-39 but much less than high index or Trivex.
High index lenses now are offered in indexs of 1.60, 1.67, 1.70, 1.71 and 1.74, with the cost going up in proportion to the index. In general the high index lenses are very close in nature to the CR-39, except the price range runs from 10 to 20 times the cost of the CR-39 lenses. Because of this prohibitive pricing, high index is only used when needed due to the high nature of the prescription they are trying to produce.
The final lens material to discuss is Trivex. It is a new product made from cast nylon, only on the market for about 5 years and growing in popularity. It has the scratch resistance and optical qualities of CR-39 lenses while offering the impact resistance of polycarbonate. The price of the Trivex lenses has begun to come down, and as this happens, the popularity of the lenses keep growing. So it is not unthinkable that in the future it could be Trivex that leads the pack in the race to be the most popular lens material on the market.
If you have any questions about the materials that might be right for you, please leave us a question or comment below. We are here to help you find what you need.
Learn more about CR-39 lenses.