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arXiv · 1604.06493

Laser-heating-based active optics for synchrotron radiation applications

Fugui Yang·Ming Li·Xiaowei Zhang
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Abstract

Active optics has attracted considerable interest from researchers in synchrotron radiation facilities, because of its capacity for x-ray wavefront correction. Here, we report a novel and efficient technique for correcting or modulating a mirror surface profile based on laser-heating-induced thermal expansion. An experimental study of the characteristics of the surface thermal deformation response indicates that the power of a milliwatt laser yields a bump height as low as sub-nanometer scale, and that variation of the spot size modulates the response function width effectively. In addition, the capacity of the laser-heating technique for free-form surface modulation is demonstrated via a surface correction experiment. The developed method is a promising new approach towards effective x-ray active optics coupled with at-wavelength metrology techniques.

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Fugui Yang, Ming Li, Xiaowei Zhang. 2016-04-22. Laser-heating-based active optics for synchrotron radiation applications. https://doi.org/10.1364/ol.41.002815

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