Swept source optical coherence microscopy using a 1310 nm VCSEL light source.
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.
Department of Electrical Engineering & Computer Science and Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, MA, USA.
Osman O
OO
Ahsen
Yuankai K
YK
Tao
Benjamin M
BM
Potsaid
Yuri
Y
Sheikine
James
J
Jiang
Ireneusz
I
Grulkowski
Tsung-Han
TH
Tsai
Vijaysekhar
V
Jayaraman
Martin F
MF
Kraus
James L
JL
Connolly
Joachim
J
Hornegger
Alex
A
Cable
James G
JG
Fujimoto
D004867:Equipment Design; D019544:Equipment Failure Analysis; D006801:Humans; D007089:Image Enhancement / Q000295:instrumentation*; D007834:Lasers; D008029:Lighting / Q000295:instrumentation*; D008853:Microscopy / Q000295:instrumentation*; D041623:Tomography, Optical Coherence / Q000295:instrumentation*