Most patients can enjoy NXT lenses in their general purpose sunglasses, sport sunglasses, or any recreational eyewear.
NXT lenses are made from Trivex material but they are designed and sold as sun lenses.
THE PRO ATHLETE Professional athletes all over the world wear NXT lenses because of the enhanced visual and physical experiences NXT lenses provide. These highly technological lenses feature proprietary tint technology with refined peripheral vision. This gives athletes a visual edge over their opponents.
Candidates for NXT lens material include just about anyone who enjoys spending time outdoors.

NXT lenses may be made with Trivex material but they can stand on their own merits.

I bet you’ve heard of Trivex lens material, right? Sure, nearly every ECP has. Not as many ECPs are aware of Trivex’s sibling however, a product known as NXT. This material has many qualities and advantages and it fits nicely into most practices. NXT is a registered trademark of Intercast Europe S.r.l. which is an Essilor International company.

Trivex lens material has been around for over a decade and its popularity has been increasing because of its impact and scratch resistance, along with its high Abbe value, clarity, and good chemical resistance. It’s also exceptionally popular for rimless eyewear because of its light weight and lens stability. Trivex material is unique because it combines the advantages of CR-39, polycarbonate, and a mid-index lens.

The material we call Trivex today got its start in the military where it was originally used for Apache helicopter windshields and later used for eyeglass lenses under combat conditions. In 2001, PPG Industries, Inc. introduced the material to the ophthalmic world and Trivex lenses were born. Lenses made with Trivex material provide extreme impact resistance, optical purity, and ultra lightweight qualities.

NXT lenses are made from Trivex material so they have all the features and benefits that Trivex lenses have. The difference is Trivex lenses are sold in the prescription eyewear channel while NXT lenses are designed and sold as sun lenses. This means that NXT lens technology focuses on providing performance sunwear lenses that deliver an array of benefits through the lens material’s features and a variety of lens tints, coatings, and other options. You’ll find them used in many plano sunwear brands but they’re also made in prescription lens form for those wanting Rx lenses. PPG sold the NXT business to Essilor this past April.

NXT has impressive ballistic-type impact resistance since it was originally designed for military use. It was created to protect chopper pilots and combat troops from harmful situations like shrapnel from a hand grenade. While Intercast doesn’t advertise it as meeting ballistic-level standards, early demonstrations of the material used a block of the material with shotgun pellets embedded in it to illustrate the kind of impact resistance it had. NXT lenses are capable of passing the stringent Z87.1 high velocity lens test, which means they are the most impact-resistant industrial safety eyewear lenses sold.

Intercast touts that NXT lenses have excellent optical clarity, even when the lens power is high. This is because the Trivex material used to make NXT lenses is very clear. It also has a relatively high Abbe value (falling between 43 and 45, depending on the lens brand) so chromatic aberration is not a problem for NXT lenses. That’s good news for those eyeglass wearers who want sunglasses with their prescription in them. It is the best lens material for mild-to-moderate prescriptions.

While NXT is super impact resistant, it’s surprisingly lightweight. In fact, NXT is the lightest commonly used ophthalmic lens material weighing in at 1.11g/cm3. Compare this to 1.21 g/cm3 for polycarbonate, 1.36 g/cm3 for 1.67, and 1.32 g/cm3 for CR-39 (and other ADC materials), and you’ll understand its lightness. When comparing the same mass of materials, these values indicate that NXT is 9% lighter than polycarbonate and 22% lighter than 1.67 and CR-39. That means NXT lenses provide the comfort sunglass wearers want.

NXT lenses are also chemically resistant so they are not affected by common solvents found in the office, home, and recreational environments, which can damage some other lens materials. Your patients will also be pleased to know that when they’re outdoors, their NXT lenses are protecting their eyes by providing 100% UV absorption. Since the lens material inherently absorbs UV radiation, no dye or coating is needed to obtain this protection.

NXT lenses are ideal for rimless eyewear creations because they are not sensitive to stress cracking. This means that when they are drilled, they do not develop stress cracks around the drill hole, which is often responsible for the lenses cracking during wear. NXT lenses also resist hole elongation. Over time, polycarbonate lenses are known to have their drill holes stretch (elongate) in rimless eyewear over time and the lenses “rattle” on the mounting. NXT lenses resist this problem and thereby keep drilled lenses secure.

These lenses dye easily and hold their color well over time. This gives ECPs the flexibility to provide just about any color and get creative with special color options like unique gradients, triple tints, etc.

NXT’s main focus is on the plano market and because of its properties, it’s ideal for fashion sunwear and sports performance plano sunwear. It’s also a terrific Rx sun lens. NXT works best with Rx’s that fall between +3.00D and -3.00D. This Rx range represents 85% of all prescription lens wearers in the U.S. so it covers nearly nine out of 10 of your Rx lens patients. Using aspheric design lenses and depending on frame design, some ECPs will use it up to +/-5.00D.

Candidates for NXT lens material include just about anyone who walks into your practice and enjoys spending time outdoors such as bus drivers, police officers, letter carriers, skiers, boaters, etc.

NXT lenses are very versatile so they come in an array of lens designs and options. You’ll find them in clear form so that you can dye them to your patient’s favorite color. There are also available in fixed tints as well as photochromic, polarized, and photochromic/polarized options. In addition, some sun lens manufacturers have developed special proprietary tints, treatments, and options for their sunwear so NXT will appear in these special configurations too. This means that most patients can enjoy them in their general purpose sunglasses, sport sunglasses, or almost any type of special recreational eyewear.

In addition, NXT lenses come in stock and semi-finished versions. This makes them ready for most prescriptions and different lens designs so you can fit your patients. Since it surfaces well, NXT is suitable for creating free-form progressives and single vision lens designs. With NXT, your Rx sun lens patients can have the latest in free-form lens technology and won’t have to accept some lesser progressive lens design because they want Rx sun lenses. It also makes NXT ideal for wrap sunwear.

Trivex lens material might have the limelight in the Rx lens market but NXT is a sun lens that every ECP should know about. Its many properties make it a terrific sun lens choice.

Robert Martinez is a licensed optician and owner of Palo Alto Eyeworks, Palo Alto, CA.

Ed De Gennaro is Director, Professional Content of First Vision Media Group.


Intercast USA


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