Fluid-Filled Tunable Lens

An electronic device may include a lens module with a tunable lens. The tunable lens may include multiple adjustable fluid-filled bladders distributed around the periphery of the tunable lens. Fluid may be selectively added to and removed from each adjustable fluid-filled bladder to control a displacement of a lens element at a given position along the periphery. The fluid may be added to and removed from the adjustable fluid-filled bladders by fluid-controlling components. The fluid-controlling components may be positioned locally within a ring-shaped chassis portion and adjacent to a respective bladder or may be consolidated in an additional chassis portion and connected to the bladders using fluid channels through the ring-shaped chassis portion. The fluid-controlling components may include stepper motors with two subassemblies that each have a ring-shaped magnet between two coils.