AN ACTUATION MECHANISM FOR VARIABLE FOCAL LENGTH EYEGLASSES

摘要

Variable power eyeglasses of many shapes can be manufactured having a frame, a pair of lens assemblies and a linear actuation mechanism. Each lens assembly includes: a rigid substrate; a membrane support spaced from the rigid susbtrate; a flexible seal extending between the rigid substrate and the membrane support, where the flexible seal acts as a hinge at a first section and acts as a spring by allowing relative motion between the rigid substrate and the membrane support at a second section; a transparent elastomeric membrane sealed around a periphery to the membrane support; and a transparent liquid filling the space between the rigid substrate and the membrane forming a liquid lens. The linear actuation mechanism causes relative motion between the membrane and the rigid substrate so that both optical and prismatic power of the liquid lens change by varying a force applied to the flexible sealing means at the second section. The linear actuation mechanism is positioned within a plane of the lens assemblies and includes: a pair of sliders connected via a wire passing through a tube mounted onto the frame; a pair of cams with one of the cams attached to each end of the pair of sliders; and a pair of cam followers responsive to the cams causing relative motion in response to movement of the sliders.