Provided is a display device capable of reliably moving a micromirror to a parking position when operation is stopped. A head-up display device drives a DMD element on the basis of electric power from a battery power supply. The head-up display device is provided with: a DMD controller for performing control of the DMD element on the basis of the electric power from the battery power supply; a voltage monitoring circuit for monitoring the voltage of the battery power supply; and a backup power supply for supplying power to the DMD controller as a backup of the battery power supply. When the voltage of the battery power supply which has been monitored by the voltage monitoring circuit falls to or below a threshold value, the DMD controller moves the DMD element to the parking position on the basis of the electric power from the backup power supply.