Spatially resolved detection of the scattering coefficient and the capillary network of tissue by using a random laser

• Applicant: Professor Dr.-Ing. Michael Schmidt
• Subject Area: Biomedical Systems Technology ; Measurement Systems ; Production Automation and Assembly Technology
• Term: from 2019 to 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 414732368

• Final Report Year: 2025

Final Report Abstract

This project advanced the understanding and application of random lasers (RLs) in biomedical optics, with an aim on the use of a RL for determining scattering properties and capillary networks in tissues. RLs, characterized by their ability to lase without a traditional cavity, offer a novel approach to probing tissue changes due to their sensitivity to changes in the scattering medium. The primary objectives included studying the behavior of RLs in phantoms, developing methods for determining scattering coefficients, and exploring RL potential for capillary network mapping. Significant progress was achieved, including the successful development of a characterization method of RL threshold regime and a mathematical model of RL peak shifts for optical properties sensing, as well as the development of a whispering gallery mode (WGM) laser for capillary detection. These findings highlight RL’s promise as a transformative optical tool in the field of medical diagnostics.

Publications

• Random laser as a potential tool for the determination of the scattering coefficient. Biomedical Optics Express, 12(9), 5439.
  Hohmann, Martin; Späth, Moritz; Ni, Dongqin; Dörner, Dominique; Lengenfelder, Benjamin; Klämpfl, Florian & Schmidt, Michael
  
• Random laser-assisted whispering gallery mode laser for precise determination of microstructures. Frontiers in Optics + Laser Science 2023 (FiO, LS), JM7A.82. Optica Publishing Group.
  Ni, Dongqin; Späth, Moritz; Klámpfl, Florian; Schmidt, Michael & Hohmann, Martin
  
• Threshold behavior and tunability of a diffusive random laser. Optics Express, 31(16), 25747.
  Ni, Dongqin; Späth, Moritz; Klämpfl, Florian; Schmidt, Michael & Hohmann, Martin
  
• Towards a sensing model using a random laser combined with diffuse reflectance spectroscopy. Biomedical Optics Express, 15(8), 4425.
  Ni, Dongqin; Klämpfl, Florian; Schmidt, Michael & Hohmann, Martin