Abstract: Light therapy in the visible spectral region, for which radiation sources emitting UV radiation are provided, uses fluorescent films that age during operation such that the intensity of the light irradiated by the fluorescent films gradually decreases. In order to solve this problem, the invention relates to a radiation converter located in a treatment device and comprising a fluorescent layer (2) for emitting the visible light. Said radiation converter comprises a housing (1) that can be penetrated by radiation emitted by the radiation source (11). The housing (1) comprises a front wall (3) consisting of a UV-permeable material and a rear wall (4) consisting of a UV-impermeable material, on the side of the housing (1) opposing the front wall (3). A liquid chamber (5) is formed between the front wall (3) and the rear wall (4), and the fluorescent layer (2) is arranged between the front wall (3) and the rear wall (4).

Abstract: The invention relates to an irradiation device and method for the treatment of totally or partially cell-mediated inflammations of the skin, the connective tissue and the viscera, viral and other infectious diseases such as HIV and prionic infections, fungal infections of the skin and the mucous membranes, bacterial diseases of the skin and the mucous membranes as well hand eczema and anal eczema which comprises at least one irradiation device to irradiate a surface treatment area where the wavelength of the emitted radiation to a treatment area is longer than 400 nm and comprises at least one spectral band between 400-500 nm while the radiation device contains means for the generation of optical pulses towards a treatment area with a power density of the optical pulse peaks larger than 0.5 W/cm2 and smaller than 100 kW/cm2. The energy of one pulse relates to 0.05-10 J/cm2.