Optical apparatus (64) includes a stator assembly (47), which includes a core (78, 90, 91) containing an air gap and one or more coils (80, 92, 94, 116, 120) including conductive wire wound on the core so as to cause the core to form a magnetic circuit through the air gap in response to an electrical current flowing in the conductive wire. A scanning mirror assembly (45, 83, 85, 130) includes a support structure (68), a base (72), which is mounted to rotate about a first axis relative to the support structure, and a mirror (46), which is mounted to rotate about a second axis relative to the base. At least one rotor (76, 132) includes one or more permanent magnets, which are fixed to the scanning mirror assembly and which are positioned in the air gap so as to move in response to the magnetic circuit. A driver (82) is coupled to generate the electrical current in the one or more coils.