A display device may include a display configured to emit light for displaying an image, a microlens array on the display and configured to collimate the image incident from the display so as to be delivered to the eyes of a user, the microlens array including a refractive index conversion layer in which a refractive index varies from region to region, and an optical path adjustment layer configured to collect light, emitted from the display and transmitted by the microlens array, and to space the display and the microlens array a preset distance apart from each other. Here, the refractive index conversion layer may include a polymer and liquid crystal molecules that interact with the polymer.