Regensburg 2022 – wissenschaftliches Programm
KFM 5.9: Vortrag
Montag, 5. September 2022, 12:45–13:00, S053
Compressed fingerprint spectroscopy based on scanning microscopy — •Bernd Kästner1, Manuel Marschall1, Arne Hoehl1, Andrea Hornemann1, Gerd Wübbeler1, Selma Metzner1, Piotr Patoka2, Eckart Rühl2, and Clemens Elster1 — 1Physikalisch-Technische Bundesanstalt, Berlin, Germany — 2Freie Universität Berlin, Germany
The infrared spectral region between 400 and 4000 cm−1 is called the fingerprint region, because the absorption features are unique to individual organic substances. Such a spectrum usually contains many peaks, making it difficult to link individual peaks to the substance. Consequently, the spatial mapping of substances requires spectral imaging, where at each point in space a complete spectrum needs to be recorded. Usually this can be achieved by spectrometers equipped with array detectors. Recently, scanning methods based on the optical nearfield and local thermal expansion with nanoscale spatial resolution have been developed allowing sub-diffraction spectral imaging. However, the inherently serial recording severely limits their imaging application due to long acquisition times involved and the resulting stability issues. In this work we demonstrate different strategies to significantly reduce the measurement time in spectral imaging measurement by compressing the measurement combined with a low-rank matrix reconstruction. Several examples from different fields of application will be discussed.