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Information × Registration Number 0226U002132, (0125U000215) , R & D reports Title Study of nonlinear responses to laser irradiation of biological media with strong light scattering popup.stage_title Створення засобів вимірювання нелінійної рефракції та поглинання, які забезпечують велике співвідношення сигнал/шум при сильному світлорозсіянні Head Sokolov Volodymyr O., Кандидат фізико-математичних наук Registration Date 09-02-2026 Organization Institute of Magnetism NAS of Ukraine and MES of Ukraine popup.description1 Study of nonlinear optical properties of organic media of plant and animal origin, as well as the effects of laser radiation propagation caused by them. Nonlinear responses of the refractive index, absorption coefficient, fluorescence quantum yield and other characteristics contain information about the processes of structural modification (diffusion and osmotic movement of fluid, shift of equilibrium in ligand exchange, etc.). Such information is not only of scientific interest, but is also already used, in particular, in the development of new methods of treating diseases. popup.description2 The developed measuring devices use a scheme in which a change in the refractive index under the action of pump radiation is converted into a shift in the center of gravity of the probe radiation spectrum. This conversion is performed using a sensor based on a semiconductor laser with an external feedback loop. A significant reduction in the effect of scattered probe radiation on the informative signal is achieved through filtering in the waveguide of the active medium, as well as in the Bragg cell. Due to much higher signal to noise relation in comparison with that of conventional techniques arises a possibility to study the media where the scattering is greater than 50%. An original calibration method was developed, the essence of which is to simulate a change in the refractive index under the action of a pumping pulse by changing the sound frequency in the cell.. To test the created means, a study of the refractive and fluorescent responses of polyvinyl alcohol hydrogel and aerosil films was carried out. The obtained data demonstrate the possibility of developing the new type optical sensors of biomarker gases for health diagnostics. Product Description popup.authors Ganna I. Kovtun Dmytro O. Derecha Yaroslav P. Lazorenko Olha Y. Saliuk Vita Mitsai Serhii Mamilov popup.nrat_date 2026-02-09 Close