The penetration depth of optical radiation depends on the wavelength. Whilst shortwave radiation (UV radiation) and longwave IR radiation are already absorbed on the surface of the skin or the eye, the visible radiation and radiation in the vicinity of the infrared range of the spectrum penetrates deep into the tissue or skin. The type and seriousness of the effects caused by optical radiation also depend on the intensity of the radiation and the long-term dosage. Potential injuries are varied and usually irreversible.