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arXiv · 1007.4613

Very long optical path-length from a compact multi-pass cell

Dipankar Das·Andrew C. Wilson
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Abstract

The multiple-pass optical cell is an important tool for laser absorption spectroscopy and its many applications. For most practical applications, such as trace-gas detection, a compact and robust design is essential. Here we report an investigation into a multi-pass cell design based on a pair of cylindrical mirrors, with a particular focus on achieving very long optical paths. We demonstrate a path-length of 50.31 m in a cell with 40 mm diameter mirrors spaced 88.9 mm apart - a 3-fold increase over the previously reported longest path-length obtained with this type of cell configuration. We characterize the mechanical stability of the cell and describe the practical conditions necessary to achieve very long path-lengths.

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Dipankar Das, Andrew C. Wilson. 2010-11-21. Very long optical path-length from a compact multi-pass cell. https://doi.org/10.1007/s00340-010-4337-7

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