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arXiv · 1809.09766

Microresonator soliton dual-comb imaging

Chengying Bao·Myoung-Gyun Suh·Kerry Vahala
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Abstract

Fast-responding detector arrays are commonly used for imaging rapidly-changing scenes. Besides array detectors, a single-pixel detector combined with a broadband optical spectrum can also be used for rapid imaging by mapping the spectrum into a spatial coordinate grid and then rapidly measuring the spectrum. Here, optical frequency combs generated from high-$Q$ silica microresonators are used to implement this method. The microcomb is dispersed in two spatial dimensions to measure a test target. The target-encoded spectrum is then measured by multi-heterodyne beating with another microcomb having a slightly different repetition rate, enabling an imaging frame rate up to 200 kHz and fillrates as high as 48 MegaPixels/s. The system is used to monitor the flow of microparticles in a fluid cell. Microcombs in combination with a monolithic waveguide grating array imager could greatly magnify these results by combining the spatial parallelism of detector arrays with spectral parallelism of optics.

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Chengying Bao, Myoung-Gyun Suh, Kerry Vahala. 2019-07-31. Microresonator soliton dual-comb imaging. https://doi.org/10.1364/optica.6.001110

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