Characterization and Optimization of Field of View in a Holographic Waveguide Display

摘要

The narrow field of view (FOV) limits the application of a holographic waveguide structure in the augmented reality display. The FOV in broadband spectrum HWDs was discussed systematically. The parameters of a volume grating are studied to reveal the relativities between the FOV and these parameters. The optimized scheme is proposed to achieve the largest FOV. To further enlarge the FOV, a multilayered grating structure is applied and a rigorous simulation model is built to verify it.The paper presents the characterization of the field of view (FOV) in a holographic waveguide display (HWD) with a broadband spectrum image source. The influences of parameters such as grating slanted angle of volume holographic grating (VHG), grating period, and effective refractive index are systematically analyzed. We optimized the parameters and calculated the maximum FOV of monochromatic and chromatic HWD. A multilayered VHGs structure is proposed to enlarge the FOV effectively without additional cost and optical design. We also build a rigorous simulation model to verify the feasibility of the multilayered structure. The theoretical maximum FOV of monochromatic and chromatic HWD are presented after optimization.