265 East Main St.
East Hampstead, NH


Getting the right lenses and coating for your vision, fashion and eye protection needs is a complicated business. Fortunately for you, it’s OUR business to help you select lenses and coatings that fit your prescription, budget and lifestyle. Here’s a little info can help you understand your lens choices, and separate the gimmicks from the goods.

Basically, there are 5 types of materials that we make glasses with out there:

     Glass     CR-39     High-Index     Trivex     Polycarbonate

All eyeglass lenses must meet federal standards; some shops require theirs to pass even higher optical hurdles.

The cheapest and has the best optics of all the lenses, but it’s heavier and, even worse, can shatter.

The future’s plastic, and there are four types:

The standard lens used for prescriptions that aren’t too strong, plus or minus 3 and lower. (CR stands for “Columbia resin,” the material used for airplane windshields during World War II; 39 refers to the recipe number.) CRs usually cost about $89 to $119 for single-vision lenses, not including coatings that can add another $50 or so the total (we’ll get to coatings in a minute).

When you get into the “blind as a bat” category, higher than plus or minus 4, it’s time think about trading up to high-index lenses. (How in the world do eyeglasses work, and what do all these numbers mean? Find out.)

High-index lenses are made from a denser material than CRs, so they’re thinner and lighter. Not all high-index lenses are the same, though. Lenses with higher indexes of refraction (IORs) bend light more efficiently; the higher the IOR, the thinner the lenses and the steeper the price. High-index lenses cost about $70-$150 more than CRs depending on just how thin you want them.

Lenses made with Trivex are ultra-light; it blends
the benefits of lightness and thinness, often resembling the thinness
of a high index lens, but weighing even less than polycarbonate.

Trivex material also provides high impact resistance as well as blocking 100% of the sun’s harmful UV
rays. And it’s an excellent choice for
rimless (or drill-mount) frames and lightweight fashion frames.

The lens of choice for kids and athletes because it’s the most impact-resistant (it’s the same stuff used in bulletproof glass) and also has a high IOR, but not the best visual properties (???? Go figure – we put kids in a lenses that’s safe but has the worst optics of all materials??). State law requires us to sell ***ONLY*** polycarbonate to kids under 18.

A tip: Because the material is so flexible and soft, it is therefore highly scratchable; no coatings will really help reduce that issue. You can skip the UV protective coating too, since the material has built-in ultra-violet protection. With these lightweight, slim lenses, which are priced in the same ballpark as high-indexes, you’re primarily paying for the extra durability.

The downside of polys is that they have a lot more distortion than other thin lens options. So unless you spend more time on the basketball court than in your car, go with high index.