**5. Feasibility Analysis**

Currently, VR and AR glasses on the market usually use liquid crystal displays (LCD) or organic light-emitting diodes (OLED), which are very good for 2D display, but cannot be used as SLM. LCoS is a kind of display module in SLM, and it has a compact structure, which is suitable for 3D HMDs; because its size is about on inch, its resolution is currently up to 4K, and its minimum pixel pitch reaches 3.74 μm. The viewing angle of holographic HMD can be 16.4◦, which is wide enough for near-eye display. Furthermore, with the development of lasers and other light sources, it is easy to get enough high intensity of readout light with a small size and low energy consumption. Therefore, true 3D HMD with a high brightness, high resolution, large viewing angle, and depth cue will be easy to obtain by holography with the development of SLMs. We believe that holographic 3D display for VR and AR can meet the requirements of near-eye display.
