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In this study, a near-eye display system is presented based on a dual-layer holographic light-guide structure. Each holographic light-guide is generated with wavelength multiplexing for color display and is designed to offer half FOV for the whole system. The full FOV of the system can reach 50°. The holographic light-guide utilized Volume Holographic Optical Elements (VHOEs) with linear grating function as the in-coupler and out-coupler. For a light-guide display, the full-color information light must propagate in the light-guide within Total Internal Reflection (TIR) condition. Therefore, it is imperative that the device must employ the gratings with distinct periods for directing red, green, and blue information light. Then the information light with different colors must propagate in different light-guides, in order to prevent crosstalk and ghost noise induced by Raman-Nath gratings, such as surface relief grating, with different periods. In comparison, the VHOEs can record the gratings with distinct periods on a single material with low crosstalk because of their strong wavelength selectivity. In the wavelength multiplexing process, each photopolymer material recorded three gratings for red, green, and blue images. Each grating primarily affects the information light of its corresponding color and guides the information light with different colors into the same light-guide within the TIR condition. In our case, a single waveguide provided the color images with about 25 degrees horizontal FOV. The diffraction efficiency of the primary information light is much larger than crosstalk noise.
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