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arXiv · 2007.10804

Accelerating speckle suppression by a degenerate cavity laser with an intracavity phase diffuser

Simon Mahler·Yaniv Eliezer·Hasan Yılmaz·Asher A. Friesem·Nir Davidson·Hui Cao
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Abstract

Fast speckle suppression is crucial for time-resolved full-field imaging with laser illumination. Here, we introduce a method to accelerate the spatial decoherence of laser emission, achieving speckle suppression in the nanosecond integration time scale. The method relies on the insertion of an intracavity phase diffuser into a degenerate cavity laser to break the frequency degeneracy of transverse modes and broaden the lasing spectrum. The ultrafast decoherence of laser emission results in the reduction of speckle contrast to $3\%$ in less than 1 nanosecond.

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Simon Mahler, Yaniv Eliezer, Hasan Yılmaz, Asher A. Friesem, Nir Davidson, Hui Cao. 2020-07-21. Accelerating speckle suppression by a degenerate cavity laser with an intracavity phase diffuser. https://doi.org/10.1515/nanoph-2020-0390

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