Yin Kun, Lee Yun-Han, He Ziqian, Wu Shin-Tson
Opt Express. 2019 Feb 18;27(4):5814-5823. doi: 10.1364/OE.27.005814.
Volume Bragg gratings (VBGs) have many applications, including filters, wavelength multiplexing devices, and see-through displays. As a kind of VBGs, polarization volume gratings (PVGs) based on liquid crystal polymer have the advantages of nearly 100% efficiency, large deflection angle, and high polarization selectivity. However, previous reports regarding PVGs did not address high efficiency, tunable periodicity, and flexibility. Here, we report a stretchable, flexible, and rollable PVG film with high diffraction efficiency. The control of PVG by mechanical stretching is investigated, while the Bragg reflection band shift is evaluated quantitatively. Moreover, we quantified the deflection angle change's behavior, which has promising potential for laser beam steering applications. The mechanical robustness under stretch-release cycles is also scrutinized.
体布拉格光栅（VBG）有许多应用，包括滤波器、波长复用器件和透视显示器。作为一种VBG，基于液晶聚合物的偏振体光栅（PVG）具有近100%的效率、大偏转角和高偏振选择性等优点。然而，先前关于PVG的报道并未涉及高效率、可调周期性和灵活性。在此，我们报道了一种具有高衍射效率的可拉伸、柔性且可卷曲的PVG薄膜。研究了通过机械拉伸对PVG的控制，同时定量评估了布拉格反射带的移动。此外，我们量化了偏转角变化的行为，这在激光束转向应用中具有广阔的潜力。还对拉伸-释放循环下的机械鲁棒性进行了研究。
