The process of infrared radiation - electromagnetic - is, in very simple words, about thermal effect. We can specify three types of IR waves: IR-A, IR-B, IR-C. In IR radiators used in cosmetology, including our Swan, IR-A radiation is mainly used. It is because the shortest infrared waves can penetrate the deepest and heat-up the most intensively. IR-A wave penetrates the outer layer of the epidermis 0,5 mm from the skin surface, then goes through the dermis layer 1-3 mm under the skin surface and finally reaches the subcutaneous tissue. The general rule concerning wavelengths is their inverse proportionality regarding the ability of tissue penetration - the shorter the wave the less ability to penetrate deep into the skin. The IR wavelength is between 780 nanometers and 1 millimeter. Wonderful effect of IR reduces skeletal muscle tension, has an analgesic effect increasing the threshold of pain sensation, increases metabolism and stimulates skin's thermal receptors. It expands the skin's blood vessels, increases thermogenesis and stimulates deeper vessels.