Scanning dual-comb spectroscopic microscopy for multidimensional optical information acquisition

We developed a scanning dual-comb spectroscopic microscopy (S-DCSM) system to acquire multidimensional optical information of transparent or semi-transparent samples. The system demonstrated the capability to perform spectral imaging of absorbance, optical phase, optical thickness, linear dichroism, and birefringence within the spectral range covered by optical frequency combs (OFCs). The spatial distribution of optical thickness in HeLa cells was measured as 8.19 ± 0.34 μm, aligning with known cellular dimensions. Additionally, the S-DCSM system was applied for the imaging of polarization-dependent optical properties, such as linear dichroism and birefringence in cellophane tape, whose spatial distributions were determined as 0.00464 ± 0.00043 and -0.014 ± 0.072, respectively, at 1560.25 nm. These results demonstrate the system's versatility in combining spatial imaging with detailed spectral and polarization information, providing a powerful tool for advanced optical characterization. This study marks a significant step forward in multidimensional optical information acquisition, facilitating detailed quantitative analysis in materials science and biological studies.