Vehicle head-up display (HUD)

A vehicular head-up display for displaying an image to a user of a vehicle having a windshield includes an image projector outputting a collimated image and an optical aperture expander. The optical aperture expander includes a light-guide optical element (LOE) having two major external surfaces (30a, 30b). The image projectorinjects the collimated image so as to propagate within the LOE by internal reflection at the major external surfaces. The LOE also has a set of parallel partially-reflecting internal surfaces which progressively couple out the image illumination from the LOE. The optical aperture expander is deployed such that the image illumination coupled-out of the LOE follows a light path including a reflection from a surface associated with the windshield of the vehicle so as to be visible to the user while the user looks at a scene beyond the windshield.