The Science

Full-body LED light therapy

The Science of Light

Photobiomodulation has been studied for decades. Here is the published research, the institutions writing about it, and the measured output of every device we make.

The spectrum

Different wavelengths reach different depths.

Blue works at the surface. Red and near-infrared travel further. The research is organised around these bands, and so are our devices.

400500600 700800900 nm 415 Blue 633 Red 660 850 Near-infrared Surface Deepest reach

Wavelengths used across the Spacetouch range, plotted on the visible and near-infrared spectrum.

Selected reading

What researchers and institutions have published.

Each link opens the original source in a new window. We have quoted them as they wrote it.

Journal of the American Academy of Dermatology
2025 · International expert consensus

A 21-member panel on clinical photobiomodulation

Built through systematic review and two Delphi rounds until unanimous agreement. States that PBM is a safe treatment modality for adult patients and red light PBM does not induce DNA damage.

Read the consensus
Journal of the American Academy of Dermatology
2024 · Continuing medical education review

Photobiomodulation in dermatology

Defines the field as light in the red (620–700 nm) and near-infrared (700–1440 nm) spectrum, and describes it as non-invasive with a favourable safety profile.

Read the review
Wellman Center for Photomedicine
Massachusetts General Hospital · 2013

How light is absorbed by cells

Photons are absorbed by mitochondrial chromophores, increasing electron transport, ATP production and nitric oxide release. The mechanism paper the field is built on.

Read the paper
Cleveland Clinic
Health Library

A consumer guide to LED light therapy

Plain-language explanation of the modality and who should avoid it. Notes that while LED light therapy seems to be safe in the short term, there's less information about its long-term safety.

Read the guide
UCLA Health
2025

Five health benefits of red light therapy

States that photobiomodulation seems to have significant health benefits with few adverse effects, while noting researchers are still determining optimal duration and frequency.

Read the article
NASA
Technology Transfer · 2022

From growing plants in orbit to medical research

Red and blue LEDs developed to grow plants in space were later studied for wound healing by university researchers, funded through NASA's small-business research programme.

Read the article
MASCC / ISOO
2019 · Clinical practice guideline

The field's only formal dosimetry guideline

The Multinational Association of Supportive Care in Cancer issued evidence-graded recommendations for photobiomodulation with specified dosimetry — for oral mucositis in cancer care.

Read the guideline
Photobiomodulation dosimetry
Published reviews

Why more is not better

The response is biphasic. Too little light does nothing; too much does less. Reviews place the useful range at roughly 5–50 mW/cm² and 1–20 J/cm² — which is why we publish both figures for every device.

Read the review
Reviver handheld device
Measurement

Watts describe electricity. Milliwatts per square centimetre describe light.

Most devices publish wattage, because it is the larger number. It tells you what the device draws from the wall, not what arrives at your skin. A device can consume a great deal of power and deliver very little light.

Irradiance is the figure the research is written in — and it is meaningless without a stated measurement distance. Ours carry one.

Our numbers

Measured output, published in full.

Every figure below was measured by the manufacturer at a stated distance. Compare them against the papers above yourself.

Galaxa
450 · 590 · 633 · 850 nm
38.0
Capsule
450 · 590 · 633 · 850 nm
30.0
Reviver — Blue head
415 nm
12.4
Solos — Red mode
660 + 850 nm
10.2
Reviver — Red head
630 + 850 nm
9.2
Solos — Dual mode
660 + 440 + 850 nm
7.3
Solos — Blue mode
440 + 850 nm
6.0
Cosmo Pro — Red
635 / 842 nm
4.28
Cosmo — Blue
467 nm
1.87

Irradiance in mW/cm². Panels measured at 10 cm; handheld heads measured at the treatment window.

Cleared indications

Three of our devices are FDA-cleared.

Spacetouch Vega, Jupiter and Neptune are cleared under K210545 for the treatment of facial wrinkles in adults using red and infrared light, and mild-to-moderate inflammatory acne in adults using blue light.

Clearance is specific. It covers those devices, those wavelengths and those indications — and nothing beyond them.

Jupiter handheld device

About the sources on this page. The organisations and researchers cited here write about photobiomodulation as a field. None has tested, reviewed or endorsed a Spacetouch product, and nothing here is a claim about our devices. Links go to the original publications so you can read them in full.

Spacetouch devices are not intended to diagnose, treat, cure or prevent any disease, except as cleared under K210545 for Vega, Jupiter and Neptune. If you take photosensitising medication or are being treated for a skin condition, speak to your doctor before using light therapy.