How to buy a light therapy mask
What light therapy actually is
Light therapy is simple to describe: skin is exposed to specific wavelengths of light, at a meaningful intensity, on a regular schedule. No heat doing the work, no needles, no abrasion. Just light, in narrow bands that decades of research have focused on. It is a routine, not a procedure: the studies that measured changes did it over weeks of consistent use, not overnight.
That is also the honest limit of the category. Light therapy is cosmetic care you do at home. Anyone promising the results of a medical procedure from a mask is selling past what the evidence says.
How we got here
It started in clinics, with lasers. The first observations that light could change skin and hair came from laser experiments in the late 1960s, and for decades low-level light treatment lived in offices, on appointment books, at in-office prices.
Then LEDs brought it home. NASA-funded work in the 1990s showed LEDs could deliver the useful red and near-infrared bands cheaply and safely, and by the 2010s the LED face mask became the category you know: hundreds of small diodes casting a soft glow across the face.
Laser is the next wave. The newest generation of home devices puts actual laser diodes, the focused light source clinics started with, into a wearable mask. Focused beams instead of a scattered glow, reaching wavelengths like 1064nm that no consumer LED mask offers. It is the closest home devices have come to the light source this whole field began with.
The science, in plain terms
The wavelength number is the whole story
Every claim in this category hangs on a number of nanometres. Different wavelengths interact with skin differently, and how far light travels into tissue rises with wavelength:
- Blue, around 415 to 460nm. The short-wavelength outlier. Works at the surface; it is the band researchers chose when studying blemish-prone skin.
- Red, 620 to 680nm. The most-studied band in the category, and the one behind most of the skin-appearance research.
- Near-infrared, 810 to 850nm. Invisible to the eye, and it travels further than red.
- 1064nm. The deepest wavelength in consumer light therapy, and a true laser wavelength; professional systems have been built on it for years. In home devices it exists only as laser diodes.
Our research library walks each band through the published studies. Start with what the wavelength number actually means and 1064nm, the deepest consumer wavelength.
LED versus laser: scatter versus focus
An LED emits light in a wide cone, a soft, diffuse glow spread across the surface. A laser diode focuses its output into a narrow, coherent beam. Same physics as a lamp versus a pointer. Neither is "fake" light, but they are different instruments, and a device should tell you plainly which one it uses. Most masks are entirely LED. A small number, the new tier, carry true laser diodes, and any device that does must also carry a laser safety classification (more on that below). The full explainer: LED vs. laser, what is actually different.
An output figure without a distance is close to meaningless
Brands quote irradiance, milliwatts per square centimetre, as if bigger were simply better. But light falls off fast with distance, so the same device measures very differently at 0cm and at 3cm. A figure without a stated measurement distance cannot be compared with anything. Almost nobody in this category publishes the distance. Treat any bare number as marketing until a distance is attached, and read irradiance, dose, and measurement distance before trusting one.
What a real result looks like
The strongest evidence in this category comes from instrumented studies: machines counting wrinkles and measuring elasticity before and after weeks of use, not a brand asking customers if they feel glowy. When you see a percentage, ask three questions: measured by whom, on how many people, over how long. A number that arrives with all three answers is worth something. A number without them is a slogan. Our ranked read of the published research: the evidence, ranked.
How to buy a light therapy mask
Six questions separate the serious devices from the glow toys, whoever you end up buying from:
- What is the light source? LED or laser diode, and how many of each. If a listing says "laser" anywhere, ask for the laser class under IEC 60825. Class 1 is the consumer-safe answer. A laser claim with no class behind it is a word on a listing.
- Which wavelengths, exactly? Numbers, not colour names. Look for the researched bands, red and near-infrared, and note how far along the spectrum the device actually reaches.
- Is there a safety file? Photobiological testing to IEC 62471 (eye safety) and, for laser devices, the IEC 60825 class. Ask for the report, not the logo.
- Are the results measured or promised? An instrumented study with people, duration, and endpoints beats any before-and-after photo.
- Does the output figure come with a distance? If not, it cannot be compared with anything.
- What do the warranty and returns actually say? Get both in writing before paying, whatever the brand.
Light therapy beyond the face
The same wavelengths are studied well beyond skincare. Whole-body exposure through panels, beds, and wearables is its own research thread, including a body of work on muscle and recovery in athletes. If that side interests you, start with full-body light: panels, beds and wearables and what the athlete studies found.
Where we land, for the record
We built Helia to be the honest version of the laser tier this guide describes: 164 true laser diodes reaching 1064nm alongside red, near-infrared, and a blue LED mode; laser-rated Class 1 under IEC 60825; photobiologically tested to IEC 62471, Exempt Group; and a 28-day instrumented study of 33 women behind the numbers we quote. Measured changes, attributed wherever they appear, individual results always varying.
But the checklist above works on any brand, ours included. Ask everyone the same six questions. We wrote them because we like our answers.