PURPOSE: To provide a picture input device capable of supplying the various kinds of instructions from the top of a platen glass.

CONSTITUTION: This device is provided with plural reflection slits provided outside the picture valid area of the platen glass of a read part, an oscillation means for supplying oscillation signals to the platen glass, a reception means for receiving the oscillation signals from the oscillation means through reflection by the plural reflection slits of the platen glass, a detection means 13 for detecting an instructed area on the platen glass by the oscillation signals received at the reception means and a processing means 23 for performing a prescribed processing inside the area detected by the detection means 13.