Why do we use infrared light in infrared lamps to heat e.g. inflamed skin? Wouldn’t the complementary color of the skin tone be better because we know that the skin absorbs these wave lengths?

Question

Why do we use infrared light in infrared lamps to heat e.g. inflamed skin? Wouldn’t the complementary color of the skin tone be better because we know that the skin absorbs these wave lengths?

In: 4

Answer 1

Infrared goes deeper, and making infrared light is cheaper. We don’t want it to all get absorbed in the outer layer of the skin.

And even if we wanted to, actual absorption is not as simple as matching the complementary color. We can make light that looks yellow by mixing red and green light, but it’d not be absorbed by something that only absorbs actual yellow wavelengths.