Pancharatnam–Berry phase optical elements (PBOEs) have received much attention due to their ability to generate complex structured light or to manipulate the shape of a light beam. This work demonstrates a tunable liquid crystal (LC) Pancharatnam–Berry (LCPB) lens using a simple and cost-effective PB phase hologram optical setup and thermal polymerization to form an irreversible photo-patterning alignment layer. The LCPB lens with high photo-stability supports ultra-broadband operation and provides a diffraction efficiency of ${\sim}{90}\%$ throughout the visible spectral range, achieved by applying the appropriate voltages. The LCPB lens functions as a convex or a concave lens, depending on the handedness of the circularly polarized incident light, so its image reduction and magnification functions are demonstrated, and its photo-stability is characterized. The fabrication of the proposed LC PBOEs is simpler and more cost-effective than previous methods, and the irreversible photo-patterning alignment layer that is formed by thermal polymerization allows larger operational bandwidths, supporting new applications.

中文翻译：

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压控液晶Pancharatnam– Berry相透镜，具有宽带操作和高光稳定性

Pancharatnam–Berry相光学元件（PBOE）由于具有产生复杂结构光或操纵光束形状的能力而备受关注。这项工作演示了可调谐液晶（LC）Pancharatnam–Berry（LCPB）透镜，该透镜使用简单且经济高效的PB相全息图光学设置和热聚合形成不可逆的光图案对准层。具有高光稳定性的LCPB镜头支持超宽带操作，并提供$ {\ sim} {90} \％$的衍射效率在整个可见光谱范围内，通过施加适当的电压即可实现。根据圆偏振入射光的手性，LCPB透镜用作凸透镜或凹透镜，因此证明了其图像缩小和放大功能，并表征了其光稳定性。所提出的LC PBOE的制造比以前的方法更简单且更具成本效益，并且通过热聚合形成的不可逆的光图案对准层允许更大的工作带宽，从而支持新的应用。