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

Area of Science:

• Optical Engineering
• Materials Science
• Biomedical Imaging

Background:

• Mid-infrared (mid-IR) optical coherence tomography (OCT) offers unique capabilities for material and biological tissue imaging.
• Achieving high resolution and sensitivity in the mid-IR range presents significant technical challenges.

Purpose of the Study:

• To present a technically straightforward approach for high-resolution and high-sensitivity Fourier-domain OCT in the mid-IR spectral range.
• To demonstrate the system's utility for imaging novel ceramic materials.

Main Methods:

• Utilized an indium fluoride (InF3) supercontinuum source for broad spectral coverage.
• Employed a custom-designed dispersive scanning spectrometer with a single Indium Arsenide Antimonide (InAsSb) point detector.
• Operated within the 3140 nm to 4190 nm spectral range.

Main Results:

• Achieved structural OCT imaging with over 80 dB sensitivity.
• Obtained an axial resolution below 8 micrometers.
• Successfully imaged porous ceramic samples and green parts from lithography-based ceramic manufacturing.

Conclusions:

• The developed mid-IR OCT system provides a simple yet effective method for high-performance imaging.
• Demonstrated the system's capability with both specialized and inexpensive low-power supercontinuum sources.
• Highlights potential applications in advanced manufacturing and material characterization.