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.

Abstract: Structure and method for face form retention in eyeglasses and eyeglass frames for substantially preventing creep from altering the face form. The method comprises providing an eyeglass frame front having a space in the bridge region for receiving a metallic strip, providing the metallic strip having a width approximately matching the width of the space in the eyeglass frame front and a thickness that is less than its width, and fastening the metallic strip in the space in the bridge region so that the width of the metallic strip rigidifies the eyeglass frame front to retain its face form. Various specific methods and structures are disclosed.

Abstract: Structure and method for face form retention in eyeglasses and eyeglass frames for substantially preventing creep from altering the face form. The method comprises providing an eyeglass frame front having a space in the bridge region for receiving a metallic strip, providing the metallic strip having a width approximately matching the width of the space in the eyeglass frame front and a thickness that is less than its width, and fastening the metallic strip in the space in the bridge region so that the width of the metallic strip rigidifies the eyeglass frame front to retain its face form. Various specific methods and structures are disclosed.