Abstract

A rotary actuation mechanism for variable focus spectacles is disclosed. The spectacles include two variable focus lens units and a bridge therebetween. The actuation mechanism includes a rotary cam rotatably mounted on the bridge, a fingerwheel attached to the rotary cam to rotate it, a cam follower disposed in slidable contact with the peripheral surface of the rotary cam, and two elongated couplers pivotally mounted on the bridge. The peripheral surface of the rotary cam is spiral shaped to transfer the rotation of the rotary cam into a linear, or pivoting, motion of the cam follower. Each coupler has a proximate end in contact with or attached to the cam follower and a distal end coupled to a linkage anchor of a respective lens unit, to transfer the motion of the cam follower into simultaneous pivoting motions of the linkage anchors thereby adjusting the focal lengths of the lens units.

IPC Classes  ?

• G02C 9/02 - Attaching auxiliary optical parts by hinging