Near-to-eye display (NED) has been widely used for augmented reality (AR) technology. Among them, holographic waveguide employing volume hologram as an input and output coupler is known to have a high diffraction efficiency compared to surface relief grating based image guide to accommodate field of view (FOV) and eyebox. However, in holographic waveguide, the FOV of volume hologram is seriously restricted, around 5 degrees. Here, we demonstrated to expand the FOV of volume hologram based input and output coupler from 5 degrees to 28 degrees and further even to 42 degrees based on polychromatic light source which mostly approaches the FOV limitation of glass-based waveguide, by utilizing multi-layer couplers or waveguides where each pair of them support portion of entire FOV.
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