A display device includes an image processing unit, a display unit, a power converter, and a transmission unit. The image processing unit is utilized for performing an image process on an image data generated by an electronic device. The display unit is coupled to the image processing unit for displaying the image data in real-time after the image process. The power converter is utilized for converting an external power generated by the electronic device to drive the image processing unit and the display unit. The transmission unit comprises a power port coupled to the power converter and the electronic device for receiving the external power.