The present invention realizes a display device with dummy pixel portions and a frame region required for the dummy pixel portions and code notation, in which the frame region is minimized while achieving code notation in required size.In a dummy pixel portion (122) of the present display device, the number of gate electrodes in a thin film transistor formed by a semiconductor layer (11) is reduced to two, so that distances from a contact hole (12) to another contact hole (13) and to a through-hole (14) can be shortened as compared to those in pixel formation portions (112a, 112b), making it possible to dispose the contact hole (13) and the through-hole (14) in a lower portion in the figure. In addition, provided in the vicinity of the center of the dummy pixel portion (122) is only an electrode equivalent to a storage capacitance line (170). Thus, a wide transparent region can be ensured to note a code (22) of a sufficient size in the dummy pixel portion (122).