Polarization grating exposure method with easily tunable period via dual rotating polarization grating masks

摘要

We introduce a new approach, to the best of our knowledge, to record polarization gratings (PGs) based on dual rotating polarization grating masks. In prior approaches, the linear variation of the orientation angle of the PG pattern was accomplished using discrete holographic optics, which require careful precision alignment, and wherein the relative distances between those optics limit the upper range of PG periods that can be made. Conversely, the setup described and demonstrated here as a single stage is very compact and more robust to vibration compared to other approaches. Moreover, this approach can easily tune the PG period while maintaining the compact size of the setup. This technique enables easy fabrication of arbitrarily large-period PGs. In this work, we discuss general design principles and critically evaluate this fabrication method, as compared to the best of prior approaches. (C) 2019 Optical Society of America