Abstract: A tool (10) is disclosed for fine machining of optically active surfaces (F), with a base body (12) that can be attached to a tool spindle of a machine tool, and an elastic membrane (14) that has a machining section (16) to which connects a gaiter section (18) by means of which the membrane is attached to the base body such that it can be rotated therewith. The base body and the membrane delimit a pressure medium chamber (20) which via a channel (22) can be optionally pressurized with a pressure medium in order to apply a machining pressure via the machining section during machining of the optically active surface. A guide element (24) guided longitudinally mobile on the base body is actively connected with the machining section so that the machining section can be moved in the longitudinal direction of the guide element and held in the transverse direction to the guide element, although under an elastic deformation of the gaiter section it is tilt-mobile in relation to the guide element.

Abstract: A tool (10) is disclosed for fine machining of optically active surfaces (F), with a base body (12) that can be attached to a tool spindle of a machine tool, and an elastic membrane (14) that has a machining section (16) to which connects a gaiter section (18) by means of which the membrane is attached to the base body such that it can be rotated therewith. The base body and the membrane delimit a pressure medium chamber (20) which via a channel (22) can be optionally pressurized with a pressure medium in order to apply a machining pressure via the machining section during machining of the optically active surface. A guide element (24) guided longitudinally mobile on the base body is actively connected with the machining section so that the machining section can be moved in the longitudinal direction of the guide element and held in the transverse direction to the guide element, although under an elastic deformation of the gaiter section it is tilt-mobile in relation to the guide element.

Abstract: A tool for the precision processing of the optical surfaces of lenses has an elastic membrane (10), connected to a rigid holder (20), which incorporates a processing segment (11) and a bellows-type segment (12). Together, the membrane (10) and the holder (20) delimit a cavity (15), which is filled with a material (16) that becomes ductile under specific conditions, and which can be induced, at will, to form a flexible or rigid supporting layer for the membrane (10). When the material (16) is in its ductile state and the processing segment (11) contacts the optical surface, the bellows-type segment (12) exerts forces on the ductile material (16) which cause it to press the processing segment (11) against the optical surface, so that the tool retains its shape after the ductile material (16) has become rigid. As this tool can be used to shape any type of optical surface, it is particularly well-suited for the processing of prescription lens eyewear.