Actuator for a Tunable Lens

A tunable lens comprising a lens element and an actuator configured to adjust a first position of the lens element, wherein the actuator comprises:

• a screw;
• a nut aligned with the screw;
• and
• first and second motor subassemblies configured to rotate the screw, wherein the first position of the lens element and a second position of the nut are adjusted when the screw is rotated and wherein each one of the first and second motor subassemblies comprises:
• a ring-shaped magnet with a plurality of sections having alternating polarity;
• a first coil;
• and
• a second coil, wherein the ring-shaped magnet is interposed between the first and second coils.

An actuator comprising:

• a housing;
• a screw enclosed by the housing;
• a nut enclosed by the housing and aligned with the screw;
• a stepper motor enclosed by the housing and configured to rotate the screw to adjust a position of the nut;
• and
• a homing sensor configured to sense when the nut is at a known home position, wherein the homing sensor comprises a conductive bar that moves in unison with the nut and at least one electrode on a wall of the housing.