What Is Near Infrared Light? A Plain Explanation
Published October 2026. Updated October 2026.
Quick answer
Near infrared (often shortened to NIR) is light with a wavelength from about 750 to 1,400 nm, just beyond the red edge of what the eye can see. It comes from the sun, from hot filaments and from LEDs, it is invisible to us, and a device that emits it needs to be judged by its spec sheet and manual, not by looks.
Where near infrared sits
Light is sorted by wavelength. Violet is shortest, red is longest, and past red the eye stops responding. That region beyond red is infrared. The part closest to red is called near infrared, because it is near the visible range, and it is the part most LED light devices use.
Standards bodies split infrared into three bands. The names below follow a common convention, and the exact edges differ a little between sources.
| Band | Approximate range | Where you meet it |
|---|---|---|
| IR A (near infrared) | About 750 to 1,400 nm | Sunlight, remote controls, night vision camera lamps, LED light devices |
| IR B | About 1,400 to 3,000 nm | Hot objects, some industrial heaters |
| IR C (far infrared) | About 3,000 nm to 1 mm | Warm surfaces, radiant heat, infrared saunas |
Approximate ranges only. Near infrared and far infrared are different parts of the spectrum, which is why a far infrared product is not the same thing as a near infrared LED panel.
Where you meet it in daily life
Near infrared is not exotic. Roughly half of the energy in sunlight at the ground is infrared, and a good share of that is near infrared. A traditional filament bulb gives off most of its output as infrared and only a small part as visible light. Many TV remotes use LEDs at about 940 nm, and many security cameras use LED lamps at 850 nm or 940 nm so they can record in the dark. The 850 nm LEDs on an AWA FX300 or AWA FX500 belong to the same family of light, driven at a much higher level.
A useful habit: if a source feels warm, some of that warmth may come from the electronics and housing and not from the light itself. That is one reason we always recommend reading a spec sheet rather than guessing from how a device feels.
Why you cannot see it
The eye has no sensitivity to light beyond about 750 nm, so near infrared is invisible even when it is bright. Some 850 nm LEDs show a dull red glow, but that is the short wavelength tail of the LED, not the near infrared. LEDs at 940 nm show almost nothing at all.
This has a practical consequence. Because the eye gives no warning, you cannot judge a near infrared source by looking at it. Use the eye protection your manual specifies, follow the timer, and do not stare at the emitters. Many phone cameras, especially front cameras, will show a near infrared LED as a pale purple or white glow. That can tell you the LED is on, but it is not a measurement of power.
The arithmetic of a wavelength
Every wavelength also has a frequency and a photon energy. Frequency in terahertz is 299,792 divided by the wavelength in nm, and photon energy in electron volts is 1239.84 divided by the wavelength in nm.
| Wavelength | Frequency | Photon energy | Band |
|---|---|---|---|
| 660 nm | About 454 THz | 1.88 eV | Red, visible |
| 810 nm | About 370 THz | 1.53 eV | Near infrared |
| 850 nm | About 353 THz | 1.46 eV | Near infrared |
| 940 nm | About 319 THz | 1.32 eV | Near infrared |
Physics arithmetic only. It describes the light and says nothing about what any wavelength does for a person.
Longer wavelength means lower photon energy. At equal power, a longer wavelength source emits more photons per second. That is physics, and our 660nm versus 850nm guide works an example.
What to check on a spec sheet
- Exact wavelength. "Infrared" on its own is not a specification. Look for a number such as 850 nm.
- Near or far. Sheets that say "infrared" may mean a heat emitter. A near infrared LED and a far infrared heating element are different products.
- Irradiance and distance. A figure in mW/cm² means little without the distance, for example the FX300 is listed at 83.5 mW/cm² at 6 inches in our irradiance specs guide.
- Per wavelength or combined. Check which one the number describes.
- Eye directions. Read the manual before the first session.
If you want to see how session time and irradiance turn into energy, the dose calculator uses J/cm² = mW/cm² x seconds / 1000. Example numbers for arithmetic only: 30 mW/cm² for 5 minutes (300 seconds) is 30 x 300 / 1000 = 9 J/cm². That number describes what a hypothetical device emits and not a target for anyone.
How AWA fits in
AWA panels list two wavelengths, 660 nm and 850 nm, paired as 30 LEDs of each. The face masks list a near infrared mode at 850 nm alongside red at 630 nm and blue at 415 nm. We describe the light and publish the figures. We make no claims about what any wavelength does for a person. For wider context, the wavelengths and devices overview is the place to start.
Common mistakes
- Using "infrared" and "near infrared" as if they were the same product category.
- Assuming a source is off because you cannot see it.
- Judging a device by how warm it feels rather than by its stated irradiance and distance.
- Reading an irradiance figure without noting the distance.
- Skipping the eye directions because the light "does not look bright".
- Using a phone camera glow as a measurement. It only shows that an emitter is on.
Before you use any light device: read the label, follow the device manual, and use eye protection as directed. Ask a doctor or other qualified professional first if you have a medical question, take medications, are pregnant, or have light sensitivity.
Related guides in this series
- 660nm vs 850nm wavelength guide
- Red light therapy explained: wavelengths, sessions and devices
- AWA FX300 and FX500 irradiance specs
- Eye protection and goggles guide
- Red light therapy formats guide
Device pages
Read the full page and label for each device before you use it: AWA FX300 panel, AWA FX500 panel. You can also browse AWA panels.
Frequently asked questions
What is near infrared light?
Light with a wavelength from about 750 to 1,400 nm, just beyond the red edge of the visible range. It is invisible to the eye.
Is near infrared the same as far infrared?
No. Far infrared sits at much longer wavelengths and is associated with radiant heat. Near infrared LEDs and far infrared heaters are different kinds of products.
Why can I not see my panel's 850 nm light?
The eye does not respond beyond about 750 nm. Any dull red glow you see is the edge of the LED's spread of wavelengths, not the near infrared itself.
Which AWA devices list near infrared?
The FX300 and FX500 panels list 850 nm. The face masks list a near infrared mode at 850 nm.
Does a longer wavelength mean a more powerful device?
No. Wavelength is a position on the spectrum. Power appears as irradiance in mW/cm² at a stated distance.
Sources
- FDA: General Wellness policy guidance (CDRH). Final guidance dated January 2026 that sets out the agency's compliance policy for general wellness products. It is a policy document, not a statement about any one device.
- FDA: Laser Products and Instruments. Describes FDA laser hazard classes I to IV, notes that higher classes carry greater risk, and states that LEDs differ from laser diodes and fall outside the federal laser product performance standard.
- FDA: Premarket Notification 510(k). Explains that a 510(k) is a premarket submission showing a device is substantially equivalent to a legally marketed device, and that a company must receive an FDA order clearing the device before marketing it in the U.S.
Regulatory note: select devices carry FDA 510(k) clearance for specific, limited uses. Most light devices are sold as general wellness products. Read each product page and label. The AWA face masks are cleared for the face only.
How we create this guide
AWA sells red light therapy devices. We write these guides to explain how devices work and how to choose and use one. This is general information, not medical advice. Read each product page and label. See our editorial standards.
