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Electromagnetic Spectrum Explorer

Light is electromagnetic radiation that travels in waves. Different wavelengths interact with your skin in different ways - from UV rays that trigger vitamin D synthesis to red and infrared light used in photobiomodulation therapy.

Interactive Spectrum

Click on any wavelength band to learn more about its properties

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Electromagnetic Spectrum100nm1100nmUV-C100-280nmUV-B280-315nmUV-A315-400nmViolet380-450nmBlue450-495nmGreen495-570nmYellow570-620nmRed620-700nmNIR700-1100nmSkin Penetration DepthStratum CorneumEpidermisDermisSubcutaneousLegendUVVisibleInfraredClick any band to learn more
Ultraviolet (UV)
100-400nm

UV light is invisible but powerful. UV-B triggers vitamin D production and melanin synthesis, while UV-A penetrates deeper and contributes to tanning and aging. UV-C is blocked by the atmosphere.

Visible Light
380-700nm

The only light we can see! Different wavelengths appear as different colors. Red light (630-670nm) is particularly interesting for its cellular effects through photobiomodulation.

Near-Infrared (NIR)
700-1100nm

Invisible to our eyes but felt as warmth. NIR penetrates deepest into tissue, reaching muscles and joints. Used therapeutically for pain relief and healing support.

Key Concepts

Wavelength & Energy

Shorter wavelengths (like UV) carry more energy per photon than longer wavelengths (like infrared). This is why UV can cause DNA damage while infrared primarily produces heat.

Penetration Depth

Longer wavelengths generally penetrate deeper into tissue. Red light reaches 2-3mm while near-infrared can penetrate 5-10mm or more, reaching muscles and joints.

Chromophores

Molecules that absorb specific wavelengths are called chromophores. Melanin absorbs UV, while cytochrome c oxidase in mitochondria absorbs red and near-infrared light.

Therapeutic Windows

Not all wavelengths are equally useful therapeutically. Research has identified optimal wavelengths: UV-B (290-315nm) for vitamin D, red (630-670nm) and NIR (810-850nm) for photobiomodulation.

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