SAD
Lux
For SAD lamps, the important question is not only how much lux a brand claims, but at what distance that number is delivered.
Buyer glossary
Light Therapy Terms That Actually Affect What You Buy
This glossary is written for buyers, not for engineers. Every term below explains what it means, why it matters before you buy, and how brands often misuse it in marketing.
SADAcnePanelsSafetyAll
Short λ400nm (Blue)
Long λ850nm (NIR)
Optical Physics Fundamental
Wavelength Determines Depth, Irradiance Determines Dose
Terms that mislead buyers most often
If you only learn four terms before shopping, make them these.
Panels
Irradiance
This is the panel metric that shapes dose, but only when distance and measurement method are named clearly.
All
Wavelength
Different categories depend on different wavelength logic, so buyers should treat vague wavelength language as a warning sign.
Safety
UV-free
This matters most for long-session white-light products such as SAD lamps and should be supported by real verification language.
Buyer-friendly glossary
Use these cards to translate technical language into purchase decisions.
SAD
Lux
What it is
A measure of visible brightness reaching your eyes.
Why buyers should care
For SAD lamps, the important question is not only how much lux a brand claims, but at what distance that number is delivered.
How brands misuse it
Brands often print '10,000 lux' as a headline while hiding that the lamp only reaches it at an impractical distance.
Panels
Irradiance
What it is
The amount of optical power delivered to a surface area, often shown in mW/cm2.
Why buyers should care
This is the panel metric that shapes dose, but only when distance and measurement method are named clearly.
How brands misuse it
A panel can look powerful on paper by using a friendly meter or a misleading test distance that buyers would never actually use.
All
Wavelength
What it is
The region of light, shown in nanometers, that tells you what kind of light you are dealing with.
Why buyers should care
Different categories depend on different wavelength logic, so buyers should treat vague wavelength language as a warning sign.
How brands misuse it
Some products imply clinical specificity with broad color labels like 'blue' or 'red' while disclosing no meaningful wavelength details.
Safety
UV-free
What it is
A claim that the device does not emit harmful ultraviolet light in a meaningful amount.
Why buyers should care
This matters most for long-session white-light products such as SAD lamps and should be supported by real verification language.
How brands misuse it
The phrase is often used like a trust badge even when the brand gives no hint about how the claim was tested.
Safety
Flicker
What it is
Rapid changes in light output caused by the device electronics.
Why buyers should care
Flicker can affect comfort and confidence, especially in products used near the face or for repeated daily sessions.
How brands misuse it
A brand may say 'flicker-free' without clarifying test conditions, brightness level, or driver design.
Panels
Beam angle
What it is
The width of the light spread coming out of an LED or panel lens.
Why buyers should care
For red-light panels, beam angle changes how concentrated or spread out the treatment area feels at a given distance.
How brands misuse it
A tight beam can make a panel look stronger at the center while hiding the trade-off in overall coverage.
Long-tail term pages
These pages show how glossary terms can scale into standalone search-entry definitions.
Irradiance
Definition, buyer meaning, and how panel brands misuse the term.
10,000 lux
What the number means in SAD lamp shopping and why distance changes everything.
Wavelength
Why red, blue, and near-infrared wording matters before you buy.
Beam angle
How spread and concentration affect panel shopping decisions.
UV-free
Why the claim matters for SAD lamps and long-session comfort.
Flicker
How electronics quality affects comfort and trust.
Photobiomodulation
What PBM means and why technical brands use the term.
Use the terms in context
SAD lamp hub
See how lux, glare, and UV-free claims change what a good SAD lamp looks like.
Explore
Acne blue-light hub
See how wavelength and protocol clarity shape acne-device buying decisions.
Explore
Red and NIR panel hub
See how irradiance, beam angle, and panel size fit together in practice.
Explore
Compare and methodology
Move from terminology to side-by-side comparison and trust scoring.
Explore