The best sunglasses lens material depends on what you ask of the lens. Glass gives the sharpest optics and resists scratches best, but it is heavy and can shatter. Polycarbonate is light and very impact-resistant, but it scratches easily and has more colour fringing. Nylon (polyamide) sits between them: light, flexible and clear. CR-39 and Trivex are two more plastics worth knowing. Lens material does not decide UV protection, so check the label whatever you buy.
Below we go through each material, compare them side by side, and match them to travel, sport and everyday wear.
TL;DR
- Glass: best clarity and scratch resistance, but heavy and the least impact-resistant. Poor fit for sport, kids or a bag that gets tossed around.
- Polycarbonate: light and the most impact-resistant, with a lower optical clarity. It needs a scratch-resistant coating.
- Nylon: light, flexible and clearer than polycarbonate. A strong pick for wraparound and performance frames.
- CR-39 and Trivex: plastics with higher clarity than polycarbonate. Trivex is also tough.
- UV protection: Health Canada says price, colour or darkness do not show how much UV a pair blocks. Look for a UVA and UVB label.
Table of Contents
- The main sunglasses lens materials at a glance
- Glass lenses
- Polycarbonate lenses
- Nylon (polyamide) lenses
- CR-39, Trivex and TAC
- Side-by-side comparison
- Which lens material suits you
- What the lens material does not decide: UV protection
- Our perspective on lens materials
- Foldable sunglasses with polarized UV protection
- FAQ
- Sources
The main sunglasses lens materials at a glance
Most sunglasses lenses are one of five things: glass, polycarbonate, nylon, CR-39 or Trivex. A sixth, TAC (tri-acetate cellulose), appears mostly in polarized film layers and budget lenses.
Health Canada puts the basic split simply: plastic lenses are tougher than glass and less likely to shatter, and it recommends a scratch-resistant coating on them. That one line explains why plastic dominates the market, and why coatings matter.
Three properties do most of the work when you compare materials:
- Optical quality. How sharp and colour-true the view is. Opticians describe this with the Abbe value: a higher number means less colour fringing.
- Impact resistance. Whether the lens survives a drop, a stray ball or a knock.
- Weight and scratch resistance. What you feel after eight hours, and how the lens looks after a year in a bag.
You rarely get all three at once. The choice is deciding which one you can live without.
Glass lenses
Glass is the benchmark for optics. The EyeWiki lens materials reference from the American Academy of Ophthalmology describes glass as having superior optical quality and the most scratch-resistant surface, but being heavy with low impact resistance.
That last point matters more than people expect. For protective eyewear, the University of Toronto’s safety standard states that current glass lenses do not meet CSA Z94.3 impact criteria and are not recommended for safety spectacles. If a lens can fail badly when hit, you do not want it near a bike, a trail or a child’s face.
Choose glass if: you wear sunglasses mostly for driving, café patios and walking around town, and you care about the cleanest image.
Skip it if: you hike, run, paddle, travel light, or toss your glasses in a bag.
Polycarbonate lenses
Polycarbonate is the workhorse of sport and safety eyewear. An aviation-safety brochure from the FAA notes that polycarbonate lenses are lighter than CR-39 and the most impact-resistant lenses available, with built-in UV protection. A Canadian optometry clinic, Mayfair Optometric, calls it especially suitable for sports, safety glasses and children’s eyewear, while noting somewhat less optical clarity and more scratch susceptibility than glass or CR-39.
The clarity gap comes from a low Abbe value. EyeWiki explains that polycarbonate’s low Abbe value means greater chromatic aberration, with colour fringing most noticeable in strong prescriptions. Patent literature gives the typical figures: about 30 for polycarbonate against 58 for CR-39. For plano (non-prescription) sunglasses the difference is usually subtle. For a strong prescription, you will notice it more.
Polycarbonate scratches easily, so a hard coating is not optional. Our own deeper look at how scratch-resistant coatings and materials compare covers what to expect from them.
Choose polycarbonate if: impact is the priority, as with kids, cycling, running, or any sport with flying objects.
Nylon (polyamide) lenses
Nylon is the material many shoppers have not heard of, and it gets few searches, but it is common in performance sunglasses. According to ZEISS Sunlens, nylon lenses are lightweight, flexible and clearer than polycarbonate, which suits wraparound, cycling, running and fashion-forward designs. The same guide says polycarbonate is more impact-resistant than nylon, which makes it better for high-impact sport and safety.
SunDefeat’s guide agrees on the character of each: nylon offers clarity, flexibility and toughness, while polycarbonate is the lightweight workhorse whose lower Abbe value can produce more chromatic distortion. Both of those are manufacturers’ own guides, so treat the exact figures as indicative and ask a retailer for the specification of a specific pair.
If you are weighing these two head to head, we go further in nylon vs polycarbonate for foldable frames.
Choose nylon if: you want a lens that bends rather than breaks, sharper vision than polycarbonate, and a curved, sporty frame.
CR-39, Trivex and TAC
CR-39 is the original optical plastic. It has a low refractive index (about 1.49) but a high Abbe value of about 58, according to the same patent reference, so its optics are excellent for a plastic. It is heavier than polycarbonate and less impact-resistant. The FAA brochure notes polycarbonate’s scratch-resistant coating is stronger than the one applied to CR-39. CR-39 is a good choice for fashion sunglasses where impact is a lesser concern.
Trivex is a newer plastic that combines clear optics with strong impact resistance. Our write-up on Trivex versus polycarbonate gives Abbe values around 43 to 45 for Trivex against roughly 30 for polycarbonate. It is usually a prescription-lab option, so ask your optician for it by name.
TAC is a thin cellulose film. It is mostly used to protect a polarizing layer sandwiched inside a lens, and on its own it is a budget material with modest optics. Treat it as a feature of a lens construction rather than a premium material.
Side-by-side comparison
This table summarizes how the materials compare, based on the sources above. “Moderate” means in the middle of the group rather than a measured value.
| Material | Optical clarity | Weight | Impact resistance | Scratch resistance (uncoated) |
|---|---|---|---|---|
| Glass | Best | Heaviest | Lowest | Best |
| Polycarbonate | Lower (Abbe about 30) | Light | Highest | Low, needs coating |
| Nylon | Higher than polycarbonate | Light | Strong, below polycarbonate | Needs coating |
| CR-39 | High (Abbe about 58) | Moderate | Moderate | Moderate, coated |
| Trivex | High (Abbe about 43 to 45) | Light | High | Needs coating |
Which lens material suits you
Travellers and commuters
You want light, tough and forgiving. Glasses live in a bag, a jacket pocket or a carry-on, and they get squeezed. Polycarbonate or nylon is the sensible choice here, and the frame matters as much as the lens. Lightweight frames cut fatigue on long days, as we explain in TR90 versus acetate for all-day travel. If you are going somewhere sunny, our guide to packable UV400 sunglasses for high-UV destinations is a useful next step.
Runners, hikers and cyclists
Nylon is attractive for runners and hikers because it flexes and stays clear. For cycling and triathlon, where a crash or flying gravel is a real risk, polycarbonate’s impact rating counts for more. If you are shopping for that kind of gear, a specialist page on sports eyewear for triathlon and cycling shows what the category looks like. On the trail, grip and stability matter too: see our notes on foldable trail sunglasses for technical runs.
Golfers and casual outdoor players
On the course, the lens is rarely the first thing to fail. The scratch usually comes from loose storage. A flat, padded spot in the bag solves most of it, and this piece on keeping sunglasses flat in a golf bag covers the practical side. Pair a scratch-coated plastic lens with good storage and it lasts.
Drivers and city wearers
Glass or CR-39 give the cleanest image for long drives. Add polarization: Health Canada notes that polarizing lenses cut reflected glare and suit driving and outdoor activities on snow or water. For water in particular, see our checklist of specs for packable polarized water sports sunglasses.
Kids
Choose impact-resistant plastic. Mayfair Optometric lists children’s eyewear among the best uses for polycarbonate. Our comparison of glass and polycarbonate lenses for travel and kids goes through the trade-offs.
What the lens material does not decide: UV protection
This is the mistake we see most. Lens material does not tell you how much UV a pair blocks. Health Canada advises shoppers to look for a label stating UVA and UVB protection and says price, colour or lens darkness do not indicate how much UV protection you get.
A dark lens with no UV filter is worse than a light one with it, because your pupils open behind a dark lens and let in more unfiltered light. The FAA brochure adds that polycarbonate has built-in UV protection, but that is no reason to skip the label.
A quick routine before you buy:
- Find the UVA and UVB (or UV400) statement on the tag or product page.
- Check the coating: scratch-resistant for plastics.
- Decide on polarization if you drive, fish, paddle or ski.
- Look at the frame: does it fit your face and survive your bag?
For the details, see our guides to UVA versus UVB protection and confirming UV400 protection in five quick checks. If you work outdoors, remember your skin needs cover as well: this guide to sun protection for outdoor workers covers the skincare side.
Our perspective on lens materials
We design glasses that fold small, so we think about what happens to a lens when it is carried, not just worn. A lens spends more of its life in a pocket, a pouch or a carry-on than on your face. That changes the question from “which material is best” to “which one survives your real week”.
Our view is plain. For most active people, a lightweight plastic lens with a proper hard coating beats glass, because it removes the risk of shattering and the weight. Among plastics, nylon and polycarbonate each win a different job, and the honest answer is that clarity and impact resistance trade against each other. Whatever the material, UV protection should be a given, not an upgrade, and polarization is worth adding if you spend time near water, snow or roads.
That is also why we pair a screwless frame with a waterproof pouch. A lens is only as durable as the way it is stored, and a foldable frame that slips flat into a pocket gives it far less chance to get scratched or crushed.
— Thomas
Foldable sunglasses with polarized UV protection
If you want to carry good lenses without the bulk, our foldable frames use a patented micro hinge and a screwless build, and come with a waterproof pouch. Our sunglasses are polarized with UV protection, in several styles and materials. Browse the full foldable sunglasses collection, the wider sunglasses range, or our prescription eyeglasses.
To see how a clear-lens style looks, try the DEVON Gunmetal+Crystal frame, or compare the ACE Gunmetal+Crystal. Buying for a team? Our collections work well as employee gifts.
FAQ
Is polycarbonate or glass better for sunglasses?
It depends on the priority. Glass has the best optics and scratch resistance, but it is heavy and can shatter. Polycarbonate is light and far more impact-resistant, but it scratches easily and needs a hard coating. For active use, travel and kids, polycarbonate is usually the safer choice.
Is nylon better than polycarbonate for sunglasses?
Not across the board. Nylon is generally clearer and more flexible, which suits wraparound and performance styles. Polycarbonate wins on impact resistance, which suits high-impact sport and safety use. Pick nylon for clarity and comfort, polycarbonate for maximum protection against impact.
What is the best lens material for sunglasses?
There is no single best material. A lightweight plastic such as nylon, polycarbonate or Trivex fits most people who travel or exercise, and glass suits those who prioritize optical quality and rarely knock their glasses around. Whichever you choose, confirm UVA and UVB protection on the label.
Do darker or more expensive lenses block more UV?
No. Health Canada says price, colour and darkness do not indicate UV protection. Look for a label stating UVA and UVB protection instead.
Sources
- Sunglasses, Health Canada
- Lens Material Properties, EyeWiki
- Sunglasses for Pilots: Beyond the Image, FAA
- Ask the Doctor: Lens materials for sunglasses, Mayfair Optometric
- A complete guide to sunglass lens materials, ZEISS Sunlens
- Sunglass Lens Materials Guide, SunDefeat
- Protective Eye and Facewear Standard, University of Toronto
- Optical terpolymer patent with Abbe values for polycarbonate and CR-39, USPTO