A light controller includes a substrate that has an optical path opening; at least a pair of blades that is reciprocally supported on the substrate and opens and closes the optical path opening; and a driver unit that drives the opening and closing of the pair of blades. The pair of blades is displaced movably on the substrate between an open position where the optical path opening is opened and a closed position where the optical path opening is closed by overlapping with each other. The driver unit and the pair of blades are connected for driving by a transmission unit, and the transmission unit transmits drive power such that one of the pair of blades can be moved at a higher speed than the other blade within a predetermined travel range between the open position and closed position.