Han Jian, Liu Juan, Yao Xincheng, Wang Yongtian
Opt Express. 2015 Feb 9;23(3):3534-49. doi: 10.1364/OE.23.003534.
A compact waveguide display system integrating freeform elements and volume holograms is presented here for the first time. The use of freeform elements can broaden the field of view, which limits the applications of a holographic waveguide. An optimized system can achieve a diagonal field of view of 45° when the thickness of the waveguide planar is 3mm. Freeform-elements in-coupler and the volume holograms out-coupler were designed in detail in our study, and the influence of grating configurations on diffraction efficiency was analyzed thoroughly. The off-axis aberrations were well compensated by the in-coupler and the diffraction efficiency of the optimized waveguide display system could reach 87.57%. With integrated design, stability and reliability of this monochromatic display system were achieved and the alignment of the system was easily controlled by the record of the volume holograms, which makes mass production possible.
本文首次展示了一种集成自由曲面元件和体全息图的紧凑型波导显示系统。自由曲面元件的使用可以拓宽视场，而视场限制了全息波导的应用。当波导平面厚度为3mm时，优化后的系统可以实现45°的对角线视场。在我们的研究中，对自由曲面元件内耦合器和体全息图外耦合器进行了详细设计，并深入分析了光栅配置对衍射效率的影响。内耦合器很好地补偿了离轴像差，优化后的波导显示系统的衍射效率可达87.57%。通过集成设计，实现了该单色显示系统的稳定性和可靠性，并且通过体全息图的记录可以轻松控制系统的对准，这使得大规模生产成为可能。
