US Patent 11340451 Wearable display for near-to-eye viewing with expanded beam

An optical apparatus has a laser light source to direct a modulated beam toward a scan mirror. An objective lens and the mirror define a curved focal surface, with a center of curvature at the scan mirror. A numerical aperture (NA) expander conforms to the concentric curved focal surface. Pupil relay optics relay an entrance pupil to an exit pupil of the viewer, the pupil relay optics defining an optical path between entrance and exit pupils. The optical path has a curved mirror surface to transmit half of the light from the modulated beam and has a first center of curvature at the entrance pupil. A first polarizing beam splitter in the optical path receives light from the scan mirror to reflect incident light of a first polarization and transmit incident light of a second polarization. The optical path directs the modulated light beam twice to the first polarizer.