Patent application number | Description | Published |
20090146527 | PIEZOELECTRIC MICROSPEAKER USING MICROELECTROMECHANICAL SYSTEMS AND METHOD OF MANUFACTURING THE SAME - 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. | 06-11-2009 |
20090154735 | PIEZOELECTRIC MICROPHONE, SPEAKER, MICROPHONE-SPEAKER INTEGRATED DEVICE AND MANUFACTURING METHOD THEREOF - 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. | 06-18-2009 |
20090154736 | APPARATUS FOR GENERATING DIRECTIONAL SOUND AND MOBILE TERMINAL USING THE SAME - Provided are an apparatus for generating directional sound and a mobile terminal using the apparatus. The apparatus includes a signal controller for dividing and generating a reference signal into signals having three or more levels and phases, a first signal processor and a second signal processor for controlling a first signal and a second signal having levels and phases canceling each other among the signals generated from the signal controller, a central signal processor for controlling a signal having the same level and phase as the reference signal among the signals generated from the signal controller, a first speaker array and a second speaker array for converting signals output from the first signal processor and the second signal processor into sound signals and outputting the sound signals, and a central speaker for converting a signal output from the central signal processor into a sound signal and outputting the sound signal, and arranged between the first speaker array and the second speaker array. | 06-18-2009 |
20100080085 | FORCED ACOUSTIC DIPOLE AND FORCED ACOUSTIC MULTIPOLE ARRAY USING THE SAME - 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. | 04-01-2010 |
20110057458 | PIEZOELECTRIC ENERGY HARVESTER AND METHOD OF MANUFACTURING THE SAME - Provided are a piezoelectric energy harvester and a method of manufacturing the same. The piezoelectric energy harvester is configured to obtain primary voltage from a piezoelectric layer vibrated to generate voltage and secondary voltage from a magnetostrictive layer vibrated to induce a change in magnetic field and a coil surrounding the magnetostrictive layer. Thus, it is possible to obtain sufficient voltage to drive a power conditioning circuit (PCC). | 03-10-2011 |
20110140579 | ACTIVE PIEZOELECTRIC ENERGY HARVESTER WITH EMBEDDED VARIABLE CAPACITANCE LAYER AND METHOD OF MANUFACTURING THE SAME - 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. | 06-16-2011 |
20120068576 | ENERGY HARVESTING ELECTRIC DEVICE - Provided is an energy harvesting electric device capable of increasing output power. The energy harvesting electric device includes an energy harvester array including a plurality of energy harvesters, a single rectifier connected to the energy harvester array, and an output unit which is connected to the single rectifier and has a load resistance. The energy harvesters include a plurality of first energy harvesters connected to each other in parallel and a single second energy harvester connected in parallel to the first energy harvesters. The first energy harvesters have a first specific resistance higher than the load resistance and the second energy harvester has a second specific resistance higher than the first specific resistance. | 03-22-2012 |
20120133210 | HYBRID ENERGY HARVESTER AND PORTABLE DEVICE THE SAME - Disclosed are a hybrid energy harvester and a portable device including the same. The hybrid energy harvester according to an exemplary embodiment of the present disclosure includes: a thermoelectric/piezoelectric element part that includes a thermoelectric element layer generating a voltage by a temperature difference, and a piezoelectric element layer generating a voltage by any one of vibration, pressure and force; an energy source selection part that selects a voltage generated in the thermoelectric element layer or the piezoelectric element layer; and a voltage controlling part that stores the voltage in an energy storage device by controlling the voltage selected in the energy source selection part. | 05-31-2012 |
20120153773 | PIEZOELECTRIC ENERGY HARVESTING APPARATUS - Disclosed is a piezoelectric energy harvesting apparatus. The piezoelectric energy harvesting apparatus includes: a piezoelectric energy harvesting array that includes a plurality of piezoelectric energy harvesting devices converting an external vibration into electric energy; a plurality of switches that is connected in series to the piezoelectric energy harvesting devices, respectively, and fits the resonance frequency of the piezoelectric energy harvesting array to the frequency of the external vibration by adjusting the resonance frequencies of the piezoelectric energy harvesting devices through the operation of the switches; and at least one or more rectifiers that convert alternating voltage outputted from the piezoelectric energy harvesting array into direct voltage. | 06-21-2012 |
20130154439 | ENERGY HARVESTING DEVICES AND METHODS OF FABRICATING THE SAME - Energy harvesting devices are provided. The energy harvesting device includes a body, a proof mass spaced apart from the body, a cantilever extending from the body onto the proof mass, a first electrode layer on the cantilever opposite to the body, a first piezoelectric layer on the first electrode layer, a second electrode layer on the first piezoelectric layer, a second piezoelectric layer on the second electrode layer, a pair of third electrode layers on the second piezoelectric layer, and a magnetic layer between the second electrode layer and the second piezoelectric layer. Related methods are also provided. | 06-20-2013 |
20130313946 | PIEZOELECTRIC ENERGY HARVESTING ARRAY AND METHOD OF MANUFACTURING THE SAME - The inventive concept discloses a piezoelectric energy harvesting array and a method of manufacturing the same. The manufacturing method may include forming a plurality of piezoelectric energy harvesting devices; connecting masses to one side of the piezoelectric energy harvesting devices and connecting the other side of the piezoelectric energy harvesting devices facing the masses to a base; and individually tuning a resonant frequency of each of the piezoelectric energy harvesting devices to prevent mismatch of resonant frequency when the masses vibrate. | 11-28-2013 |
20140159542 | PIEZOELECTRIC ENERGY HARVESTING DEVICE AND METHOD OF FABRICATING THE SAME - A flexible piezoelectric energy harvesting device includes a first flexible electrode substrate, a piezoelectric layer disposed on the first flexible electrode substrate, and a second flexible electrode substrate disposed on the piezoelectric layer. The piezoelectric layer may include a plurality of first piezoelectric lines spaced apart from each other in one direction and a plurality of second piezoelectric lines respectively filling spaces between the first piezoelectric lines. | 06-12-2014 |