Patent ID: 11256021

Abstract:
A slab waveguide, comprising a plate having parallel surfaces and a cascade light splitting film. The plate is used for receiving and transmitting incident waveguide light which bears a transmitted image. The splitting film is disposed in the plate, intersects the upper and lower surface of the plate, and is used for reflecting the incident waveguide light out of the slab waveguide to form an actual image. In order to avoid mirror image coincidence, the waveguide needs to satisfy: |arcsin(n×sin(90°−4a+b))−arcsin(n×sin(90°−2a−b))1>2ω, wherein a is an inclined angle between the cascade light splitting film and the lower surface of the plate, b is an inclined angle between central image light of the incident waveguide light and the lower surface of the plate, ω is an image display viewing angle of the transmitted image, and n is the refractive index of the plate.