Patent attributes
An SMA actuation apparatus moves a movable element, such as a camera lens element, relative to a support structure in any direction perpendicular to a notional primary axis using N pairs of SMA actuator wires extending perpendicular to said primary axis, where N is three or more. The SMA actuator wires of each pair extend parallel to each other and being connected at their ends in tension to the movable element and the support structure in opposition to apply a force to the movable element in opposite directions. The SMA actuator wires are arranged around the movable element such that they are capable of being selectively driven to move the movable element in any direction perpendicular to said primary axis. Accordingly, it is possible to drive movement with an apparatus that is compact along the primary axis.