Light-guide optical element and method of its manufacture

An optical structure that is an intermediate work-product configured to be subdivided along a plurality of parallel dicing planes to produce two or more light guide optical elements (LOEs) configured such that each LOE comprises an optically transparent body for guiding input light in a general propagation direction through the body by total internal reflections of light from major surfaces of the body and comprises light directing surfaces for coupling the input light out of the body in one or more output directions, where the light directing surfaces are fully embedded in a volume of the body being spaced from the major surfaces of the body and are inclined with respect to said major surfaces at a predetermined angle, the optical structure being configured as a stack of multiple optically transparent layers, wherein:

• each of said optically transparent layers has a planar surface arranged in an X-Z plane and provided with a surface pattern of a plurality of elongated light directing regions having parallel extensional directions, said light directing regions being in a spaced-apart relationship along at least an X-axis with optically transparent space regions between them;
• and
• the multiple layers are stacked one on top of the other along a Y-axis such that each of the surface patterns is located at an interface between two adjacent layers and the patterns of said layers are shifted relative to adjacent layers by a predetermined shift value along one of the X-axis and the Z-axis;
• wherein said surface pattern of light directing regions and said optically transparent space regions are deployed such that dicing of the optical structure, along a plurality of parallel dicing planes intersecting with an X-Z plane and forming a predetermined angle with the X-Z plane, subdivides the optical structure into a plurality of slices spaced along said one of the X-axis and Z-axis, to produce a plurality of bodies for the LOE elements, each of said bodies having an internal array of spaced-apart, parallel, light directing regions fully embedded in the LOE's body and inclined with respect to major surfaces of the LOE body at said predetermined angle.