This scanner head includes a case member (300b) having a first side wall (300f) and a second side wall (300y), an electric circuit board (105) placed inside the case member (300b), a terminal board (309) including a terminal to be connected to the main apparatus and placed outside the first side wall (300f), a wiring unit (305) for connecting the electric circuit board (105) and the terminal board (309) through a slit opening (300c) formed in the first side wall (300f), and a shield plate (102). This shield plate (102) couples the first side wall (300f) and the second side wall (300y).