Abstract: The invention is used to ascertain a sun protection factor for light, for example for cosmetics and sunscreens for which a sun protection factor (SPF) is specified. Two measurements of the light backscattering on the skin surface are carried out in vivo or in vitro or on skin models (animal skin models or artificial skin models) before and after applying the radiation protection means onto the skin, and the sun protection factor is ascertained therefrom. In contrast to standard methods used until now, the distance between the lighting surface and the detection surface on the skin is ascertained for the irradiation path of the measurement method. The skin lighting dose used during the measurement lies below harmful limits. The sun protection factor can be ascertained according to previous standards or for additional wavelengths or wavelength ranges (e.g. UVA, VIS, NIR, IR).

Abstract: The invention relates to a non-destructive and non-invasive method for determining the concentration or other parameters of constituent substances in fluids, which method is capable of minimizing the optical interfering influences, which are unknown but constant during the individual measurement, of the vessel wall on the measurement result or the evaluation, in that measurements are carried out with different through-radiation path lengths and quotient calculations eliminate the influences of the vessel wall. Wide-area illumination and detection ensure that non-linearities occurring during said measurements do not interfere with the accuracies of the determination.

Abstract: The invention is used to ascertain a sun protection factor for light, for example for cosmetics and sunscreens for which a sun protection factor (SPF) is specified. Two measurements of the light backscattering on the skin surface are carried out in vivo or in vitro or on skin models (animal skin models or artificial skin models) before and after applying the radiation protection means onto the skin, and the sun protection factor is ascertained therefrom. In contrast to standard methods used until now, the distance between the lighting surface and the detection surface on the skin is ascertained for the irradiation path of the measurement method. The skin lighting dose used during the measurement lies below harmful limits. The sun protection factor can be ascertained according to previous standards or for additional wavelengths or wavelength ranges (e.g. UVA, VIS, NIR, IR).

Abstract: The invention relates to a non-destructive and non-invasive method for determining the concentration or other parameters of constituent substances in fluids, which method is capable of minimizing the optical interfering influences, which are unknown but constant during the individual measurement, of the vessel wall on the measurement result or the evaluation, in that measurements are carried out with different through-radiation path lengths and quotient calculations eliminate the influences of the vessel wall. Wide-area illumination and detection ensure that non-linearities occurring during said measurements do not interfere with the accuracies of the determination.