A holographic display device presents a holographic image within an external part for a vehicle such as a headlight assembly or an exterior rearview mirror assembly. An outer cover defines an interior cavity, with a transparent portion, such as a window, allowing a viewer to see into the interior cavity. A presentation surface inside the interior cavity is illuminated by an image source to display the holographic image, which appears as a 3-dimensional object within the interior cavity, and which appears to be suspended therein. The holographic image may be stationary or moving, and may include a logo, symbol, or other graphic. The image source is may be hidden from direct view. One embodiment includes two circular polarizer to prevent light directly from the image source from being visible, while allowing reflected light to become visible by being having the polarization direction reversed.