In an imaging apparatus, a detection section 9 detects a beam L_F having passed through an aperture 5 in a first direction and a location designation beam L_B having passed through the aperture 5 in the opposite direction is made incident to a position (x,y) in a first light image IM1 on an image pickup surface corresponding to a specific position (x,y) in a second light image IM2, whereby the result of detection of the beam L_F detected at the detection section 9 indicates data at a specific position in an incoming light image designated by the location designation beam L_B, regardless of whether there is a mechanical error in movement of the aperture 5.