Swept source optical coherence microscopy using a 1310 nm VCSEL light source

Abstract

Abstract:We demonstrate high speed, swept source optical coherence microscopy (OCM) using a MEMS tunable vertical cavity surface-emitting laser (VCSEL) light source. The light source had a sweep rate of 280 kHz, providing a bidirectional axial scan rate of 560 kHz. The sweep bandwidth was 117 nm centered at 1310 nm, corresponding to an axial resolution of 13.1 µm in air, corresponding to 8.1 µm (9.6 µm spectrally shaped) in tissue. Dispersion mismatch from different objectives was compensated numerically, enabling magnification and field of view to be easily changed. OCM images were acquired with transverse resolutions between 0.86 µm -3.42 µm using interchangeable 40X, 20X and 10X objectives with ~600 µm x 600 µm, ~1 mm x 1 mm and ~2 mm x 2 mm field-of-view (FOV), respectively. Parasitic variations in path length with beam scanning were corrected numerically. These features enable swept source OCM to be integrated with a wide range of existing scanning microscopes. Large FOV mosaics were generated by serially acquiring adjacent overlapping microscopic fields and combining them in post-processing. Fresh human colon, thyroid and kidney specimens were imaged ex vivo and compared to matching histology sections, demonstrating the ability of OCM to image tissue specimens.

Three-dimensional multi-contrast imaging of in vivo human skin by Jones matrix optical coherence tomography

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Volumetric imaging and quantification of cytoarchitecture and myeloarchitecture with intrinsic scattering contrast

“…Therefore, the methods presented here have potential as tools for three-dimensional connectivity mapping. Finally, although a cortical volume of only ~1 mm 3 was imaged here, in the future, we will investigate higher speed imaging methods [30] to achieve imaging volumes comparable to the complete mouse brain (~500 mm 3 ) [31]. The eventual long-term goal is to map all myelinated axons in the human brain.…”

Endoscopic optical coherence tomography: technologies and clinical applications [Invited]

“…VLE [131] and laser marking are now commercially available and are being tested in clinical trials. Another approach for comprehensive imaging of the esophagus has been the utilization of an ultra-high speed form of SS-OCT that employs a Fourier Domain Mode-locked Laser (FDML) [134] or VCSEL [135] light source. The unique capability of OCT to provide information about internal tissue structures has been employed to assess efficiency of radio-frequency ablation (RFA) of BE.…”