Facebook Reality Labs, 9845 Willows Road NE, Redmond, WA, 98052, USA.
Sci Rep. 2020 Sep 30;10(1):16127. doi: 10.1038/s41598-020-72555-w.
Foveated near-eye display is one of the most promising approaches to deliver immersive experience of mixed reality. However, it is challenged to conceive a compact optical system. Here, we introduce a method to use polarization optics via liquid crystal photonics to improve the foveated display performance. We demonstrate a benchtop prototype of this idea. We implement and combine two display modules for peripheral and foveal visions. A peripheral display consists of a polarization selective lens (PSL) module, a polarization selective diffuser (PSD), and a slanted projection system. An 80[Formula: see text] diagonal field of view is achieved by on-axis optical configuration of the PSL module and the PSD. A foveal holographic display is composed of a spatial light modulator (SLM), a volume grating lens, and a microelectromechanical system mirror possibly in combination with a switchable polarization selective grating module. The holographic reconstruction using the SLM enables accurate focus cue generation and high resolution above 30 cycles per degree within 15[Formula: see text] by 15[Formula: see text] field of view. We explore and discuss the liquid crystal photonics in the prototype that has a novel optical design using volume gratings with polarization selectivity.
注视点近眼显示是提供混合现实沉浸式体验最有前途的方法之一。然而,设计一个紧凑的光学系统仍然具有挑战性。在这里,我们介绍了一种利用液晶光子学中的偏振光学来提高注视点显示性能的方法。我们展示了该想法的一个台式原型。我们实现并组合了两个用于周边和注视点视觉的显示模块。一个周边显示由偏振选择透镜(PSL)模块、偏振选择漫射器(PSD)和倾斜投影系统组成。PSL 模块和 PSD 的轴上光学配置实现了 80[Formula: see text]对角线视场。一个注视点全息显示由空间光调制器(SLM)、体积光栅透镜和微机电系统反射镜组成,可能与可切换偏振选择光栅模块结合使用。使用 SLM 进行全息重建可实现精确的焦点提示生成,在 15[Formula: see text]×15[Formula: see text]视场中,分辨率高于 30 周/度。我们探索并讨论了原型中的液晶光子学,该原型采用了具有偏振选择性的体积光栅的新颖光学设计。