Light of cellular water are raised in temperature by the infrared radiation. EMR in this range causes molecular vibration and heating effects, which is how these animals detect it. Above the range of visible light, ultraviolet light becomes invisible to humans, mostly because it is absorbed by the cornea below 360 nm and the internal lens below 400 nm. Furthermore, the rods and cones located in the retina of the human eye cannot detect the very short (below 360 nm) ultraviolet wavelengths and are in fact damaged by ultraviolet. Many animals with eyes that do not require lenses (such as insects
Ultraviolet light therapy that tanning beds that primarily emit UVA cannot be effective for the treatment of psoriasis. Other limitations to the use of tanning beds for the treatment of skin conditions include the imprecise output of the lamps and beds, imprecise spectral targeting of commercial tanning beds, the fact that the patient or non-medical staff run the machines, and other acute or long-term side effects. Ultraviolet light therapy Ultraviolet light therapy or ultraviolet phototherapy is a form of treatment for certain skin disorders including atopic skin disorder and vitiligo when used with psoralen to form the PUVA treatment. It consists of irradiation