Nanoimprinted Meta-Mirror Surfaces for Reflection Phase Control for High Resolution Displays

In extended reality (XR), virtual reality (VR) and augmented reality (AR) devices, micro-displays are required to have ultra-high PPI, high brightness, superior color purity, and so on. Particularly for near-eye displays, which are positioned extremely close to the user's field of view, it is critical to maintain sufficient brightness after passing through the optical system [1]. It is also important to prevent color mixing between pixels due to optical cross-talk. However, it is very difficult to avoid the optical cross-talk at very high pixel densities [2]. Recently, directional light emission has been studied as one of the solutions to solve these problems. Various methods such as micro-cavity and Distributed Bragg Reflector(DBR) can be used to increase the directional light emission. However, these approaches are not suitable for real micro-display process because the thickness of micro-cavity and DBR should vary depending on the color. So, meta-surface based directional emission and color improvement is emerging as another alternative technology.