Abstract: An objective lens actuator is provided. An objective lens holder is movably located on a ferromagnetic yoke with corresponding to inner yokes thereof to hold an objective lens. Tracking coils and focusing coils are respectively located on different two opposite sides of the lens holder and the latter are surrounded with the inner yokes. A magnetic element set is located on the ferromagnetic yoke corresponding to the coils to generate a magnetic field perpendicular to the optical axis of the lens. A suspension wire set is connected to the lens holder and the coils to hang the lens holder and channel current to the coils. A damper holder is located on a ferromagnetic yoke to allow the wire set to pass through. A printed circuit board is located on the damper holder and coupled with the wire set to provide the current to the coils, to drive the lens holder.

Abstract: An optical head to access data on an optical recording medium, which has two data storage densities, includes two sets of optical path systems to provide two optical paths that are crossed. Each optical path system includes a laser light generation unit, a light guiding unit, a converging objective lens and a photo detector. The light guiding unit is located on the optical path of the laser light generation unit, to direct the laser light to pass through the converging objective lens and focus on the data side of the optical recording medium to carry optical data signals from the data side. The laser light returns to the light guiding unit and travels along the optical path and is received by the photo detector.

Abstract: This specification discloses a piezoelectric ultrasonic motor with multi-layer thin disks. A buzzer disk made of a piezoelectric material is supplied with an alternate voltage to produce alternately expanding and shrinking deformation. An elastic vibration disk in connection with the buzzer disk produces standing waves to transport kinetic energy to the exterior. A driving module symmetric in the vertical or horizontal direction is also formed. This does not only reduce the abrasion among the components, but also provide homogeneous forward and reverse driving forces.