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bioRxiv · 10.1101/2024.08.07.606954

Single-shot impulsive stimulated Brillouin microscopy by tailored ultrashort pulses

Krause, D.·Boehm, J.·Liebig, L.·Koukourakis, N.·Czarske, J.
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Abstract

Brillouin microscopy has become an important tool for investigating the mechanical properties of tissue. The recently developed Impulsive stimulated Brillouin Scattering (ISBS) promises a label-free, non-invasive measurements of viscoelastic properties of transparent samples and offers the potential for a high temporal resolution. However, the spatial resolution of ISBS is currently limited, which hinders its transfer to real-world applications. Increasing the spatial resolution of ISBS leads to an increase in the energy density of the pump beams, which requires a balancing of the excitation parameters to stay below the phototoxic threshold. This paper focuses on the influences of different excitation parameters on the spatial, temporal and spectral resolution and their optimal values. Combined with the adoption of a noise suppressing window function, a measurement rate of 20{micro}s/pixel in hydrogel is achieved, which is promising for fast 3D imaging. The presented advanced impulsive stimulated Brillouin microscopy can be applied for fast tissue elastography to-ward disease studies.

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Krause, D., Boehm, J., Liebig, L., Koukourakis, N., Czarske, J.. 2024-08-09. Single-shot impulsive stimulated Brillouin microscopy by tailored ultrashort pulses. https://doi.org/10.1101/2024.08.07.606954

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