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arXiv · 1507.04788

Low-spatial-coherence broadband fiber source for speckle free imaging

Brandon Redding·Peyman Ahmadi·Vadim Mokan·Martin Seifert·Michael A. Choma·Hui Cao
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Abstract

We designed and demonstrate a fiber-based amplified spontaneous emission (ASE) source with low spatial coherence, low temporal coherence, and high power per mode. ASE is produced by optically pumping a large gain core multimode fiber while minimizing optical feedback to avoid lasing. The fiber ASE source provides 270 mW of continuous wave emission, centered at {\lambda}=1055 nm with a full-width half-maximum bandwidth of 74 nm. The emission is distributed among as many as ~70 spatial modes, enabling efficient speckle suppression when combined with spectral compounding. Finally, we demonstrate speckle-free full field imaging using the fiber ASE source. The fiber ASE source provides a unique combination of high power per mode with both low spatial and low temporal coherence, making it an ideal source for full-field imaging and ranging applications.

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Brandon Redding, Peyman Ahmadi, Vadim Mokan, Martin Seifert, Michael A. Choma, Hui Cao. 2015-07-16. Low-spatial-coherence broadband fiber source for speckle free imaging. https://doi.org/10.1364/ol.40.004607

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