A head-mounted display, HMD, system for mounting on the head of a viewer and providing an augmented reality display to at least one eye of the viewer, the system comprising: (a) a light-transmitting substrate having a plurality of surfaces including a planar first major surface and a planar second major surface parallel to said first major surface, said first and second major surfaces (26, 32) guiding image light within said substrate by internal reflection, said plurality of surfaces further comprising an edge surface; (b) a coupling-out arrangement comprising a plurality of planar partially-reflective surfaces deployed within said substrate, said partially-reflective surfaces being parallel to each other and obliquely angled relative to said first major surface so as to couple image light out of the substrate towards the eye of the viewer in facing relation to said first major surface; (c) an optical component (40, 61, 66, 90) comprising a display source (38, 64, 100) and collimating optics (40, 82) projecting a collimated image having a central image ray defining an image light output direction, wherein said optical component (40, 61, 66, 90) is optically coupled to said substrate via a coupling prism attached to said edge surface by a prism surface that is adjacent to the edge surface, said coupling prism providing a planar coupling-in surface substantially perpendicular to said image light output direction such that said image light is injected into said substrate along said image light output direction so as to undergo a first reflection after leaving said optical component (40, 61, 66, 90) at said second major surface of said substrate, characterized said edge surface is slanted at an oblique angle to said first major surface of the light-transmitting substrate and the coupling prism is a triangular prism, wherein an edge of the coupling prism formed by the prism surface and the coupling-in surface at acute angle is positioned adjacent to an edge of the light-transmitting substrate formed at acute angle by the slanted edge surface and one of the first and second major surfaces (26, 32). (a) a light-transmitting substrate having a plurality of surfaces including a planar first major surface and a planar second major surface parallel to said first major surface, said first and second major surfaces (26, 32) guiding image light within said substrate by internal reflection, said plurality of surfaces further comprising an edge surface; (b) a coupling-out arrangement comprising a plurality of planar partially-reflective surfaces deployed within said substrate, said partially-reflective surfaces being parallel to each other and obliquely angled relative to said first major surface so as to couple image light out of the substrate towards the eye of the viewer in facing relation to said first major surface; (c) an optical component (40, 61, 66, 90) comprising a display source (38, 64, 100) and collimating optics (40, 82) projecting a collimated image having a central image ray defining an image light output direction, wherein said optical component (40, 61, 66, 90) is optically coupled to said substrate via a coupling prism attached to said edge surface by a prism surface that is adjacent to the edge surface, said coupling prism providing a planar coupling-in surface substantially perpendicular to said image light output direction such that said image light is injected into said substrate along said image light output direction so as to undergo a first reflection after leaving said optical component (40, 61, 66, 90) at said second major surface of said substrate, characterized said edge surface is slanted at an oblique angle to said first major surface of the light-transmitting substrate and the coupling prism is a triangular prism, wherein an edge of the coupling prism formed by the prism surface and the coupling-in surface at acute angle is positioned adjacent to an edge of the light-transmitting substrate formed at acute angle by the slanted edge surface and one of the first and second major surfaces (26, 32).