Patent attributes
An eye-strain reducing lens is characterized by an x-y-z coordinate system, and includes a distance-vision region, baying a non-negative distance-vision optical power, configured to refract a light ray, directed by a source at a distance-vision region point at a distance-vision x-distance from a center of the coordinate system, to propagate to an eye-center-representative location; and a near-vision region, having a near-vision optical power that matches the distance-vision optical point within 0.5 D, configured to refract a light ray, directed by the source at a near-vision region point at a near-vision x-distance from the center of the coordinate system, to propagate to the same eye-center representative location; wherein the near-vision x-distance is smaller than the distance -vision x-distance.