摘要:
An ultra-small optical/magnetic head actuator includes: a swing arm movable in a horizontal direction (tracking direction) and a vertical direction (focusing direction) and having mounted thereon a head for reading and writing information on a disk. A tracking actuator moves the swing arm in the horizontal direction (tracking direction) and a pivot hinge adjusts a radius of rotation of the swing arm and guides the movement of the swing arm in the tracking direction. A focusing actuator moves the swing arm in the vertical direction (focusing direction), wherein the focusing actuator includes a focusing coil attached under the swing arm and a Halbach magnet array disposed under the focusing coil minimizes thickness. Friction or backlash can be avoided, and non-repetitive errors can be reduced. The thickness of the ultra-small storage device can be reduced due to the use of a Halbach magnet array.
摘要:
Provided is an active piezoelectric energy harvester, which can control a direct current voltage applied to an embedded variable capacitance layer to precisely adjust a resonance frequency in real time, and thus achieve a simpler structure and a smaller size compared to a conventional one that adjusts the resonance frequency using a separate variable capacitor provided outside. Further, the active piezoelectric energy harvester can precisely adjust the resonance frequency even when the frequency of vibration varies over time as in a real natural vibration environment or when it is degraded to undergo a variation in its own resonance frequency, and thus can continuously maintain optimal energy conversion characteristics.
摘要:
A piezoelectric microphone, a speaker, a microphone-speaker integrated device and a manufacturing method thereof are provided. The microphone-speaker integrated device includes a silicon substrate and an insulating layer deposited on the silicon substrate; a piezoelectric plate formed on the insulating layer; and a mating electrode formed on the piezoelectric plate. The mating electrode is patterned with a polarity arrayed in series.
摘要:
A piezoelectric microspeaker using microelectromechanical systems (MEMS) and a method of manufacturing the same are provided. The piezoelectric microspeaker includes a piezoelectric layer disposed on an elastic thin layer, and a resonance change unit patterned on one of a bottom surface of the elastic thin layer and a top surface of the piezoelectric layer.
摘要:
Provided are an acoustic multi-pole array and methods of packaging and controlling the same. The methods include packaging first and second sound devices constituting an acoustic multi-pole array to have different sound characteristics or the same sound characteristic, arranging the first and second sound devices in tandem, and then respectively inputting sound sources having the same magnitude and different phases to the first and second sound devices to improve forward directivity and reduce a backward radiation characteristic.
摘要:
A piezoelectric speaker and a method of manufacturing the same that can obtain a high sound pressure using a piezoelectric thin film are provided. The piezoelectric speaker includes a piezoelectric thin film, electrodes formed on an upper surface or upper and lower surfaces of the piezoelectric thin film, a damping material layer formed on the lower surface of the piezoelectric thin film, and a frame attached around at least one of the piezoelectric thin film and the damping material layer using an adhesive.
摘要:
Provided is a forced acoustic dipole capable of regulating phases and acoustic pressures of first and second acoustic signals output from first and second pole speakers to freely steer the direction of an acoustic lobe. In addition, a forced acoustic multipole array is constituted by a plurality of forced acoustic dipoles. When the phases and acoustic pressures of the first and second acoustic signals output from the forced acoustic dipoles are regulated to steer an acoustic lobe in a specific direction, sound can be heard from a desired direction only without disturbing others.
摘要:
A piezoelectric microphone, a speaker, a microphone-speaker integrated device and a manufacturing method thereof are provided. The microphone-speaker integrated device includes a silicon substrate and an insulating layer deposited on the silicon substrate; a piezoelectric plate formed on the insulating layer; and a mating electrode formed on the piezoelectric plate. The mating electrode is patterned with a polarity arrayed in series.
摘要:
Provided are an interdigitated electrode (IDE) for an electronic device, which includes a plurality of anodes and a plurality of cathodes arranged radially in an alternating fashion for electrical insulation from one another, and an electronic device using the same. The IDE in which the anodes and the cathodes are arranged radially in an alternating fashion is fabricated and applied to the electronic device, so that the entire fabrication process can be simplified compared to that of a typical electronic device in which an upper electrode is different from a lower electrode. Also, circular or polygonal IDEs can be applied to systems that are driven or measure values on their central axes, thereby enhancing the performance and efficiency of the systems. Furthermore, the circular or polygonal IDEs can be employed in systems such as acoustic sensors, pressure sensors, micro-speakers, biological sensors, and acceleration sensors, so that the structure and operation of the systems can be simplified.
摘要:
A polymer actuator containing graphene and a method of preparing the same are provided. The polymer actuator includes an ion-conductive polymer membrane, a metal electrode disposed on both surfaces of the ion-conductive polymer membrane, and graphene dispersed within the ion-conductive polymer membrane. As the graphene is dispersed within the polymer membrane, reverse ion migration due to an osmotic pressure occurring after solvent migration caused by electrostimulation in operation of the actuator can be prevented, and thus drivability of the polymer actuator can be improved.