Disclosed is a display device including a transparent piezoelectric element having transparent electrodes coated on both surfaces thereof, bonded by transparent adhesive material on an inner surface of a transparent cover to be arranged in front of a display panel of the display device. The transparent cover works as a vibration generator of a sound source. The thickness of the transparent electrodes are selected to serve as an anti-reflection layer of the near ultraviolet light. Relative dimensions of and positional relation between the transparent cover and the piezoelectric element are limited in predetermined ranges to assure high quality of display characteristic and sufficient volume of sound.