Method for manufacturing substrate-guided elements for compact head-mounted display system

An optical device, comprising:

• a light-transmitting substrate having at least two major surfaces and edges;
• an input aperture;
• an output aperture;
• an eye-motion box having an aperture;
• an intermediate element positioned outside of the substrate for coupling incoming light waves, having a field-of view, into the substrate through the input aperture;
• a first flat reflecting surface, located between the two major surfaces of the light-transmitting substrate, for reflecting incoming light waves from the intermediate element to effect total internal reflection from the major surfaces of the substrate;
• a second flat reflecting surface parallel to the first flat reflecting surface, located between the two major surfaces of the light-transmitting substrate, for coupling light waves out of the substrate, and
• a redirecting optical element positioned outside of the substrate for redirecting light waves coupled-out from the substrate through the output aperture, into the eye-motion-box,
• wherein at least a first part of a light wave trapped inside the light-transmitting substrate is reflected at least once by the first flat reflecting surface before being coupled into the light-transmitting substrate through the input aperture and at least a second part of the same light wave is coupled into the light-transmitting substrate without being reflected from the first flat reflecting surface.