A display includes: a substrate having a pixel region and a sensor region in which photo-sensor parts are formed; an illuminating section operative to illuminate the substrate from one surface side of the substrate; a thin film photodiode disposed in the sensor region, having at least a P-type semiconductor region and an N-type semiconductor region, and operative to receive light incident from the other surface side of the substrate; and a metallic film formed on the one surface side of the substrate so as to face the thin film photodiode through an insulator film, operative to restrain light generated from the illuminating section from being directly incident on the thin film photodiode from the one surface side, and fixed to a predetermined potential, wherein in the thin film photodiode, the width of the P-type semiconductor region and the width of the N-type semiconductor region are different from each other.