An optical actuator is disclosed. The optical actuator includes a seat bearing the optical element, a yoke comprising an end, a suspension system comprising at least one spring sheet connecting the seat and the end, and a driving device moving the seat relative to the yoke. The spring sheet constrains the movement of the seat. The spring sheet includes an inner connecting portion connected to the seat, an outer connecting portion surrounding the inner connecting portion and connected to the end, and a spring structure disposed between the inner and outer connecting portions and connecting the inner and outer connecting portions.