An optical system comprising: (a) a light-guide optical element (LOE) formed from transparent material and having mutually-parallel first and second major external surfaces for guiding light by internal reflection; (b) a projector configured to project illumination corresponding to a collimated image from an aperture, the illumination exiting said aperture with a chief ray defining an optical axis of said projector and with an angular field about the chief ray; (c) a coupling prism attached to said first major external surface of said LOE, said coupling prism providing at least part of an image injection surface angled obliquely to said major external surfaces, said projector being associated with said image injection surface and oriented such that the chief ray and the angular field about the chief ray are injected through said image injection surface at angles of incidence relative to said major external surfaces greater than a critical angle for internal reflection at said major external surfaces; and (d) a reflective polarizing beam splitter deployed at an interface between said major external surface and said coupling prism parallel to said major external surfaces, at least part of the illumination being incident on said beam splitter with a first polarization and being transmitted by said beam splitter from said coupling prism into said LOE, light corresponding to a conjugate image of the collimated image and having a second polarization incident on said beam splitter from within said LOE being reflected from said beam splitter so as to propagate within said LOE by internal reflection. (a) a light-guide optical element (LOE) formed from transparent material and having mutually-parallel first and second major external surfaces for guiding light by internal reflection; (b) a projector configured to project illumination corresponding to a collimated image from an aperture, the illumination exiting said aperture with a chief ray defining an optical axis of said projector and with an angular field about the chief ray; (c) a coupling prism attached to said first major external surface of said LOE, said coupling prism providing at least part of an image injection surface angled obliquely to said major external surfaces, said projector being associated with said image injection surface and oriented such that the chief ray and the angular field about the chief ray are injected through said image injection surface at angles of incidence relative to said major external surfaces greater than a critical angle for internal reflection at said major external surfaces; and (d) a reflective polarizing beam splitter deployed at an interface between said major external surface and said coupling prism parallel to said major external surfaces, at least part of the illumination being incident on said beam splitter with a first polarization and being transmitted by said beam splitter from said coupling prism into said LOE, light corresponding to a conjugate image of the collimated image and having a second polarization incident on said beam splitter from within said LOE being reflected from said beam splitter so as to propagate within said LOE by internal reflection. <EOS>