DUAL SURFACE COLLIMATOR AND 3D ELECTRONIC DISPLAY EMPLOYING GRATING-BASED BACKLIGHTING USING SAME

摘要

Dual-direction collimation and a dual surface collimator provide dual-direction collimated light at a non-zero propagation angle. The dual surface collimator includes an entrance surface and a reflector surface each having a curved shape. The entrance surface is configured to refract incident light and the reflector surface is configured to reflect the refracted light back toward the entrance surface. The entrance surface is further configured to re-reflect the reflected light by total internal reflection toward an output aperture. Curved shapes and relative orientation of the entrance and reflector surfaces, in combination, are configured to convert the incident light into dual-direction collimated light having the non-zero propagation angle. A three-dimensional (3D) display includes the dual surface collimator, a plate light guide and an array of multibeam diffraction gratings to provide a plurality of light beams corresponding to different 3D view of the display.