An embodiment comprises: a housing; a bobbin for mounting a lens, the bobbin being accommodated inside the housing; a first coil disposed on an outer circumferential surface of the bobbin; a magnet disposed in the housing; and a second coil disposed in the housing, wherein the second coil comprises a third coil and a fourth coil, a first signal is applied to the first coil, a second signal is applied to the fourth coil, and an induction voltage is generated in the second coil by a mutual induction operation between the first coil and the second coil.