FAQs
The basics
What is Lightsmart?
Lightsmart makes Halo, clothing that turns sunlight into red light. Every Halo is made with UV2RED, our patented fabric technology. In the sun, Halo gives you three things at once: 30%+ more red light, UPF 50+ sun protection, and 4°F+ cooler comfort.
No batteries, no charging, nothing to remember. You just wear it outside.
How does UV2RED work?
UV2RED is built into the fiber itself. When sunlight hits the fabric, it absorbs high-energy light, including UV and blue light, and re-emits part of that energy as red and near-infrared light, the wavelengths used in red light therapy.
Ordinary sun fabrics absorb that energy too, then pass much of it to you as heat. UV2RED puts it to work as light instead. Same sunlight, different job.
Can I see the light it makes?
Mostly, no. Much of what UV2RED makes is near-infrared, which the eye can't see. That's why we measure it with a spectrometer rather than ask you to take our word for it. See how we measure →
How do you know it works?
We test outdoors in real sun. A spectrometer reads the light under the fabric, with a filter on top that blocks the sun's own red and near-infrared, so whatever the sensor picks up, the fabric made.
In our latest test, Halo Skywave delivered 66% more red and near-infrared light at the skin than without UV2RED. Two more passes that afternoon measured 46% and 40%. We claim 30%+. The full method →
How is Halo different from an ordinary sun shirt?
Both protect you from the sun. An ordinary sun shirt blocks UV and turns much of that energy into heat. Halo blocks UV too, then converts part of that energy into red and near-infrared light.
In our side-by-side test in full sun, UV2RED fabric ran up to 12.4°F cooler than a comparable fabric dyed to match. Every Halo is UPF 50+.
How is Halo different from a red light panel?
A panel gives a set dose in a set session, indoors. Halo works passively, for as long as you're outside in the light, wherever you already are. It's a different way to get red light, not a replacement for a device.
How much light
How much red light do I actually get?
It depends on the sun, the time of day, the weather and your Halo's color. At any moment on a typical day, we've measured roughly 1 to 8 mW/cm².
What matters more is the total over a day, measured in joules (J/cm²). Our Daily Forecast estimates that total for your location, date and color, along with your best window. See today's forecast →
Why do colors make different amounts?
Dark dyes absorb light, which is what makes them dark. The more light the dye keeps for itself, the less is left for UV2RED to convert. So lighter colors make more red light, and darker colors make less.
If you want black, you'll give up some output, but the fabric is still making red and near-infrared light. An ordinary dark shirt lets a little sunlight through, but it doesn't make any extra.
Every color is UPF 50+. The Daily Forecast lets you compare colors side by side.
Does it work on cloudy days?
Yes, with less output. Clouds cut the light but don't shut it off, and an overcast day still delivers a lot of energy. The Daily Forecast factors in cloud cover where you are.
Does it work in winter?
Yes, with less to work with, because the sun sits lower and the days are shorter. The bigger factor is coverage. The fabric has to see the light, so wear Halo as your outer layer when you can. Under a jacket, it can't convert light that never reaches it.
Can I wear it indoors or at night?
You can wear it anywhere. It makes meaningful red light only in strong light, best in direct sun. Near a bright window it still works, at reduced output. At night it's simply a comfortable layer.
Wearing it
How does Halo fit?
Halo FS1: use your normal performance-shirt size. If you're between sizes, size up for a relaxed fit.
Halo OG1 is one size, adjustable.
Do I still need sunscreen?
On the skin Halo covers, Halo is your UPF 50+ protection. Use sunscreen on the skin it doesn't cover, like your face, neck and hands.
How do I care for it?
Machine wash and dry according to the care label, and skip bleach and high heat. UV2RED is in the fiber, not a coating, so it doesn't wash out.
Is it safe?
Yes. There are no electronics, batteries, wires or light source. The technology is in the fiber and powered by daylight.
Halo is general-wellness apparel and isn't intended to diagnose, treat, cure or prevent disease.
Health and research
What does the research say about red light?
Scientists have studied how red and near-infrared light interacts with the body for decades, under the name photobiomodulation. Research areas include skin, performance and recovery, and joints and muscles. Most of those studies used lasers and LED panels at controlled doses.
We report what our fabric produces and link to the research rather than promising outcomes. Explore the research library →
Has UV2RED fabric been studied?
Yes. In a 12-week pilot study published in the Journal of Dermatological Treatment, dermatology researchers at Wake Forest University School of Medicine studied red and near-infrared emitting fabric, the technology behind UV2RED. They reported improvement in disease severity among patients with mild psoriasis, polymorphous light eruption, and alopecia areata. Read the study →
It was a small pilot study, and Halo isn't a treatment for any condition. It sits within a much larger body of research on red and near-infrared light, known as photobiomodulation. Halo delivers that light differently: passively, at lower intensity, across your day.
Who is Halo for?
Anyone who spends time outside: runners, walkers, golfers, cyclists, boaters, outdoor workers, and anyone who'd like their time in the sun to do more. Halo OG1 brings the same technology to your head and scalp.
Can Halo replace medical treatment?
No. Halo is general-wellness apparel, not a medical treatment. If you have a health condition, including a skin or hair-loss condition, talk to your healthcare provider.
Buying
What styles are available?
Halo FS1, a full-sleeve top for men and women, and Halo OG1, a cap. More styles are on the way.