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arXiv · 2105.04882

Time-encoded mid-infrared Fourier-domain optical coherence tomography

Ivan Zorin·Paul Gattinger·Andrii Prylepa·Bettina Heise
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Abstract

We report on a technically simple approach to achieve high-resolution and high-sensitivity Fourier-domain OCT imaging in the mid-infrared range. The proposed OCT system employs an InF3 supercontinuum source. A specially designed dispersive scanning spectrometer based on a single InAsSb point detector is employed for detection. The spectrometer enables structural OCT imaging in the spectral range from 3140 nm to 4190 nm with a characteristic sensitivity of over 80 dB and an axial resolution below 8 um. The capabilities of the system are demonstrated for imaging of porous ceramic samples and transition-stage green parts fabricated using an emerging method of lithography-based ceramic manufacturing. Additionally, we demonstrate the performance and flexibility of the system by OCT imaging using an inexpensive low-power (average power of 16 mW above 3 um wavelength) mid-IR supercontinuum source.

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Ivan Zorin, Paul Gattinger, Andrii Prylepa, Bettina Heise. 2021-09-14. Time-encoded mid-infrared Fourier-domain optical coherence tomography. https://doi.org/10.1364/ol.434855

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