As one of the most ideal display approaches, holographic 3-dimensional (3D) display has always been a research hotspot since the holographic images reproduced in such system are very similar to what humans see the actual environment. However, current holographic 3D displays suffer from critical bottlenecks of narrow viewing angle and small size. Here, we propose a tunable liquid crystal grating-based holographic 3D display system with wide viewing angle and large size. Our tunable liquid crystal grating, providing an adjustable period and the secondary diffraction of the reconstructed image, enables to simultaneously implement two different hologram generation methods in achieving wide viewing angle and enlarged size, respectively. By using the secondary diffraction mechanism of the tunable liquid crystal grating, the proposed system breaks through the limitations of narrow viewing angle and small size of holographic 3D display. The proposed system shows a viewing angle of 57.4°, which is nearly 7 times of the conventional case with a single spatial light modulator, and the size of the reconstructed image is enlarged by about 4.2. The proposed system will have wide applications in medical diagnosis, advertising, education and entertainment and other fields.

作为最理想的显示方式之一，全息3维（3D）显示一直是研究热点，因为在该系统中再现的全息图像与人类看到的实际环境非常相似。然而，目前的全息 3D 显示器存在窄视角和小尺寸的关键瓶颈。在这里，我们提出了一种基于可调谐液晶光栅的全息3D显示系统，具有宽视角和大尺寸。我们的可调谐液晶光栅提供可调节的周期和重构图像的二次衍射，能够同时实现两种不同的全息图生成方法，分别实现宽视角和放大尺寸。利用可调谐液晶光栅的二次衍射机制，所提出的系统突破了全息3D显示器窄视角和小尺寸的限制。所提出的系统显示出57.4°的视角，几乎是单个空间光调制器的常规情况的7倍，并且重建图像的尺寸扩大了约4.2倍。该系统将在医疗诊断、广告、教育和娱乐等领域有广泛的应用。