PROJECTION OPTICAL SYSTEM FOR COUPLING IMAGE LIGHT TO A NEAR-EYE DISPLAY

摘要

Techniques are described for projection optics that optically couple image light from an image source toward a near-eye display (NED) of a wearable near-eye display device. The projection optics and the image source constitute a projection light engine. Light from the image source is directed towards a birdbass reflective optical element that is embedded in high refractive index glass. The image light is reflected and collimated by the birdbass element and travels out of the housing of the projection light engine forming an external exit pupil, meaning that the exit pupil is external to the projection light engine. The waveguide optically couples the image light of the external exit pupil. An example of a waveguide that may be used is a surface relief grating waveguide.