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arXiv · 2011.00514

Ultrahigh-speed optical coherence tomography based on a 100 MHz and 100 nm swept source

Dongmei Huang·Feng Li·Zihao Cheng·Xinhuan Feng·P. K. A. Wai
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Abstract

We demonstrate an ultrahigh-speed optical coherence tomography (OCT) based on a 100 MHz swept source (SS). An all polarization-maintaining figure-9 mode-locked fiber laser is used as the seed laser. After nonlinear spectral expansion in an Erbium-doped fiber amplifier, a flat top spectrum with respectively 1-dB and 10-dB bandwidths of 73.7 nm and 106 nm is obtained. The broadband femtosecond pulse is time stretched to a swept signal in a section of dispersion compensation fiber with a total dispersion of -84 ps/nm. With the swept source, the axial resolution of the SS-OCT is measured to be 21 um with a 6 dB sensitivity roll-off length of 3 mm. A tomographic image of an encoding disk and a hard disk jointly rotating at 17,000 rpm was acquired by using the SS-OCT with a high imaging quality.

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Dongmei Huang, Feng Li, Zihao Cheng, Xinhuan Feng, P. K. A. Wai. 2020-11-01. Ultrahigh-speed optical coherence tomography based on a 100 MHz and 100 nm swept source. https://arxiv.org/abs/2011.00514

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