Low-intensity, diffuse red light is generally safe, but high-intensity, concentrated beams can cause serious, immediate damage. The risk is determined by the amount of light energy delivered to the retina and how quickly the eye can dissipate it. Red light is part of the visible light spectrum, occupying the longest wavelengths, typically ranging from 620 to 750 nanometers (nm). On the contrary, when used appropriately, it can be a key part of your eye and skin health routine.