Planar waveguide based augmented reality smart glasses with large field of view

We present a way to achieve the compact augmented reality (AR) smart glasses with a large field of view (FOV). A planar waveguide and embedded narrow band minus filters are used for image transmission and coupling. The optical system based on the method is simple in structure and has the advantages of small size and lightweight. A geometric model for the propagation of light in the waveguide is constructed. Based on this model, the constraints of the structure and the dependence of designed parameters with viewing angles are analyzed. According to the calculations, a 3 mm thick waveguide is fabricated to investigate the feasibility of the theory. Experimental results demonstrate that the prototype can deliver a projected image and realize the fusion of the virtual image and the real scene as expected, the measured viewing FOV was about 50°.