Light the body already makes — and what a film can actually do.

Three different lights

Thermal infrared. A person at rest radiates heat. The peak is far-infrared, around 9–10 micrometers — the same physics as a warm wall. Some ceramic and mineral yarns are built to interact with that band. That is a real textile category. It is not a laser.

Photobiomodulation. Clinics and labs study red and near-infrared light from powered sources, at known wavelengths and doses. That literature exists. A film on a cuff is not that experiment.

Biophotons. Living cells emit ultra-weak light. The count is tiny — typically tens to hundreds of photons per square centimeter per second. Daylight is trillions of times brighter. The phenomenon is real. Harvesting it with a filtered mirror as a substitute for low-level light therapy is a specific invention, patented by others. Elytra does not sell it.

What Elytra is

Jewelry: a metal cuff or collar with a structural-color film on the inner face. The film is a dielectric stack. It produces iridescence the way a beetle wing does — geometry, not pigment.

Knits: mineral-ceramic yarns in a wrap or cowl, with the same film as a lining. Built for people who already wear recovery layers and want one that looks like it belongs in a quiet room.