Fig. 17
From: Waveguide-based augmented reality displays: perspectives and challenges
(a Is redrawn from [1] and d, e are redrawn from [125])
Working principle of waveguide couplers shape design. a Relationship of eyebox, FoV and out-coupler size. b Relationship of microdisplay, projection lens and in-coupler size. c Relationship of LBS and in-coupler size. d Normalized \(k\)-vector diagram of the 2D EPE based on two consecutive 1D EPE, where the black arrows \({k}_{1}/{k}_{0}\) and \({k}_{2}/{k}_{0}\) represent the propagation directions of a certain FoV angle inside waveguide. e Corresponding ray tracing process of the certain FoV angle inside waveguide, where deep blue, orange and green regions represent the effective pupil expansion regions for this FoV angle