“Every time I go into a convenience store, I have to swap my sunglasses off”
People with a prescription who own a pair of prescription sunglasses often end up using them like this: sunglasses on while walking, swap back to regular glasses in the convenience store, swap again on the way out, five or six times in a morning, until they give up, put the sunglasses in the bag and squint the rest of the way.
Without a prescription, sun protection just means putting sunglasses on and taking them off. With a prescription, every time you take them off you need another pair to see clearly. That’s where the hassle comes from.
Four routes to sun protection with a prescription
Photochromic lenses: one pair all day, with trade-offs in the car and in summer
Photochromic lenses darken in UV light and slowly clear again indoors, so one pair works from morning to night with no swapping. Their drawbacks are just as consistent: the windshield blocks most UV, so they barely darken in the car; the hotter it is, the faster they fade, so at summer midday they’re lighter than in winter; and coming indoors, they take a while to clear. Why this happens is explained in how photochromic lenses work.
Prescription sunglasses: polarized or tinted, a second pair to swap
A separate pair of prescription sunglasses gives the most complete sun protection outdoors, at the cost of the scene above: swapping every time you go in and out. The lenses can be polarized or plain tinted. Polarized lenses reduce glare off roads and water and increase contrast; tinted lenses reduce light overall, with more color choices.
Clip-ons and magnetic sun lenses: attached to the pair you have
A clip-on is a sun lens that clips onto the front of your existing glasses; a magnetic sun lens attaches with magnets to a matching frame. Put it on outdoors and take it off indoors, with no second prescription pair needed, and clip-ons come in polarized versions too. The trade-off is appearance and fit: an extra layer is always a bit bulkier, and the fit against the frame and the light leaking in from the sides aren’t as good as a full pair of sunglasses. Magnetic sun lenses are matched to their frame, so a new frame means a new set.
Putting prescription lenses into non-prescription sunglasses you like
If you fall for a pair of ready-made non-prescription sunglasses in the shop, in most cases the lenses can be swapped for prescription ones. Non-prescription, fashion sunglasses are general consumer goods in Taiwan, not medical devices; once prescription lenses go in, those lenses are corrective lenses and an eye exam comes first. The more curved the frame and the stronger the prescription, the more it needs assessing first.
One pair or two: work these out first
How often you go in and out each day
The more often you go in and out, the more photochromic lenses pay off. Sales reps, delivery riders and parents on school runs, going in and out a dozen times a day, rarely keep up with swapping two pairs. If you only meet the sun on your commute and spend the rest of the day indoors, one extra pair of sunglasses kept in a fixed place is simpler.
How much you drive
If driving is your main sun-protection need, photochromic lenses won’t help much, because UV is blocked inside the car. Frequent drivers who wear photochromics day to day are still better off with a separate pair of prescription polarized sunglasses for driving.
How strong your prescription is and how curved a frame you want
With a stronger prescription, a large lens or a curved wraparound frame makes the lens edges thicker and the periphery more prone to distortion. If you want a curved sports frame, let our optometry staff assess it against your prescription first; if it can’t be done well, a clip-on or photochromic lenses may be the better route.
Photochromics, sunglasses and clip-ons compared
| Option | How it shades | Strength | Limitations | Better suited to |
|---|---|---|---|---|
| Photochromic lenses | UV triggers darkening | One pair all day, no swapping | Barely darken in the car, lighter in summer, take a while to clear indoors | People in and out of buildings many times a day |
| Prescription polarized sunglasses | Remove horizontally vibrating glare | Reduce road and water glare, increase contrast | Fixed dark tint, swap indoors; not for twilight or night driving | Frequent drivers, people often near water |
| Prescription tinted sunglasses | Reduce light overall | Wide choice of colors and frames | No glare filtering, no color change, swap indoors | People sensitive to sun who spend long weekends outdoors |
| Clip-ons / magnetic sun lenses | Attach to your existing pair | No second prescription pair needed | Extra layer on the front, less complete shading than a full pair | Occasional sun protection, keeping the pair you have |
Whichever you choose, check the UV spec, not the color
Whether a lens blocks UV depends on the material and coating specification, not on how dark it is; a very dark lens may not block it, and a clear lens can. Ask for the specification when you order.
Our Xinzhuang and Banqiao stores, and booking
All four routes are available at both our Xinzhuang and Banqiao stores. ZEISS and HOYA, the lens brands we carry, both have polarized and photochromic ranges, and tinting is available too, for myopia, hyperopia, astigmatism and progressives. Both stores sell clip-ons and magnetic sun lenses, including polarized clip-ons, and stock ready-made non-prescription sunglasses from brands such as Ray-Ban, which you can buy as they are or fit with prescription lenses. Beyond Visual does not currently offer lenses that combine polarized and photochromic in one, or photochromic lenses designed to darken inside a car.
Prescription lenses need an eye exam first; the exam itself takes about 45 to 60 minutes. Before you come, think about how often you go in and out each day, how many days a week you drive, and where you’d usually keep your sunglasses.
- Beyond Visual Optometry (BiYang Optometry Clinic), Xinzhuang store: No. 419-1, Zhongzheng Rd., Xinzhuang Dist., New Taipei City, near MRT Xinzhuang Station, +886-2-2206-6700, led by Optometrist YoYo
- Beyond Visual Optical (Beyond Visual Optometry Clinic), Banqiao store: No. 28, Ln. 47, Sec. 2, Shuangshi Rd., Banqiao Dist., New Taipei City, near MRT Jiangzicui Station, +886-2-2253-1246
Book a vision consultation, and bring the glasses you wear now and any sunglasses you already own.
Decide where the second pair will live before deciding which kind to get
People who decide on two pairs rarely think about where the second pair will spend its time. Yet whether a pair of glasses gets worn often has less to do with how good it is than with whether it happens to be within reach.
The pair kept in the car only comes out when you drive; walking, waiting for the bus or taking the kids to the park, it’s sitting in the car park. The pair in your bag has to be remembered and swapped, and by the fifth swap, most people stop. The pair in a drawer at home might as well not exist.
So think about it in reverse. First ask: where will the second pair live, and when will it come out? If the answer is “in the car,” get a pair of polarized sunglasses for driving and rely on your regular pair or photochromics day to day. If the answer is “it won’t stay anywhere,” one pair of photochromics or a clip-on may get used more than two pairs of glasses.
FAQ
Q: What are the drawbacks of photochromic lenses?
There are three main ones. They barely darken in the car, because the windshield blocks most UV; they’re lighter in summer than in winter, because heat makes them fade faster; and coming indoors, they take a while to clear, longer when it’s cold. After many years, how dark they get may also decrease. If you can live with these, they’re the least hassle; if driving is your main need, a separate pair of polarized sunglasses is more practical.
Q: Can clip-ons be polarized? Do they fit any frame?
Polarized clip-ons are available. Whether one sits securely depends on the shape and size of your current frame: the clip-on has to match the frame, since too small leaks light and too large presses on the bridge of the nose. Magnetic sun lenses are paired with a specific frame and can’t simply be moved to another. Bring the pair you wear and we’ll compare on the spot.
Q: Can someone with myopia get prescription sunglasses?
Yes. Myopia, hyperopia and astigmatism can all be made into prescription sunglasses, and so can progressives. If your prescription is strong and you want a large lens or a curved frame, lens edge thickness and peripheral distortion need assessing first. Prescription sunglasses are corrective lenses, so an eye exam comes first.
With a prescription, the hard part of sun protection has never been whether the lenses are dark enough, but whether that pair actually gets worn. Decide where it will live and when it will come out, then choose which kind to get.