Fig. 1. Schematic of diffractive waveguide principle

Fig. 2. Schematic of FOV definition. (a) Definition of H and V; (b) definition of a and D

Fig. 3. Schematic of FOV measurement method

Fig. 4. Schematic of eye-box of diffractive waveguide

Fig. 5. Schematic of eye-box of near-to-eye display module with a tilt angle

Fig. 6. Schematic of measurement method for brightness, chromaticity, and micro projector flux of diffractive waveguide.(a) Measurement principle of brightness and chromaticity; (b) measurement principle of micro projector flux

Fig. 7. Schematic of the method for evaluating the brightness of diffractive waveguides

Fig. 8. Effect of different brightness distributions on human eyes. (a) (b) Two pure green pictures with the same average brightness but different distributions

Fig. 9. Schematic of optical efficiency of diffractive waveguide

Fig. 10. Schematic of measurement method for chromaticity nonuniformity of diffractive waveguide

Fig. 11. Schematic of diffraction grating lines and stray light^[30]. (a) (b) Different scanning electron microscope photos of gratings; (c) (d) diffraction spot images generated from Fig.11 (a) and Fig.11 (b), respectively

Fig. 12. Schematic of imaging effects under different contrast^[32]. (a) (c) Imaging effect at low contrast; (b) (d) imaging effect at high contrast

Fig. 13. Measurement method of stray light^[33]