Holographic optical elements (HOEs) play an important role in augmented reality (AR) systems. However, the fabrication of full-color HOEs is difficult and the diffraction efficiency is low. In this paper, we use the time-scheduled iterative exposure method to fabricate full-color HOEs with high diffraction efficiency. Through this method, a full-color HOE with an average diffraction efficiency of 73.4% was implemented in a single photopolymer, the highest rate yet reported. In addition, the AR system is simulated by the geometric optics method combining k-vector circle and ray tracing and structured by combining laser micro-drop and high diffraction efficiency HOEs. A good color blending effect was achieved in a full-color AR system by using the reconstruction wavelength consistent with the recording light. It can present clear holographic images in a full-color AR display system.

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The relationship between refractive index modulation parameters and beam ratio is examined experimentally and theoretically for multiple-exposure holograms, both for the case of simultaneous and sequential recordings. These parameters are determined by measuring the diffraction efficiency of each main grating. Using the measurements, the optimum beam ratio for high efficiency is determined. Experimental results are in good agreement with theory.