US Patent 10429646 Free space optical combiner with prescription integration

A prescriptive see-through eyepiece includes a meniscus lens body and an optical combiner. The meniscus lens body has an external scene side with a convex curvature and an eye-ward side with a concave curvature. The optical combiner is disposed within the meniscus lens body to combine image light incident through the eye-ward side with external scene light incident through the external scene side into a combined image. The optical combiner is partially reflective and imparts substantially no lensing power to the external scene light passing through. The optical combiner along with the concave curvature of the eye-ward side are configured to impart prescriptive lensing to the image light while the convex curvature of the external scene side and the concave curvature of the eye-ward side are configured to impart the prescriptive lensing to the external scene light.