Fig. 1. Schematic diagrams of propagation in double volume holographic grating waveguide. (a) Two-dimension optical path of exit pupil expansion; (b) structure of double volume holographic grating waveguide

Fig. 2. Schematic diagrams of optical path propagation in path A. (a) Schematic diagram of light propagation path in positive field of view; (b) diagram of diffraction light propagation under grating vector

Fig. 3. Schematic diagrams of optical path propagation in path B. (a) Schematic diagram of light propagation path in negative field of view; (b) diagram of diffraction light propagation under grating vector

Fig. 4. Planar diagrams of conical diffraction light propagation path in path A. (a) Light propagation in center field of view; (b) light propagation in positive field of view

Fig. 5. Planar diagrams of conical diffraction light propagation path in path B. (a) Light propagation in center field of view; (b) light propagation in negative field of view

Fig. 6. Exit pupil diameters of double volume holographic grating waveguide. (a) Exit pupil diameter in x direction; (b) exit pupil diameter in y direction

Fig. 7. k vector diagram of general single channel waveguide

Fig. 8. k vector diagram of double holographic grating waveguide in full field of view

Fig. 9. Holographic exposure processing optical path of HOE₂₁

Fig. 10. Processed double volume holographic grating waveguide sample. (a) Double volume holographic grating waveguide sample; (b) real ray tracing and optical pupil spots in two-dimension expansion pupil

Fig. 11. Full field of view image