摘要:
Disclosed is a system of transferring wireless power using an ultrasonic wave, including: an ultrasonic wave generating device converting and transferring electric energy to an ultrasonic wave; and an ultrasonic wave receiving device receiving the ultrasonic wave to convert the ultrasonic wave to electric energy, wherein the ultrasonic wave generating device includes a radiation plate with a plurality of ultrasonic elements and controls an effective area of the radiation plate by turning on/off the plurality of ultrasonic elements so that the ultrasonic wave receiving device is disposed at a position minimizing dispersion effect due to a circular radiation of the ultrasonic wave.
摘要:
The present disclosure relates to security system and method based on sound field variation pattern. The present disclosure identifies a slow variation pattern of a acoustic transfer function occurring due to a gradual change in temperature and humidity of air according to a change in time and a change in a characteristic of an acoustic element, from a sudden sound field variation pattern within an internal space occurring due to an intrusion from an outside, activation of an air conditioning and heating device, and the like, or within a surveillance space induced by a change in an acoustic physical property. The present disclosure identifies sound field variation patterns occurring due to a change in an acoustic structure by an intrusion and a change in temperature and convection by air conditioning and heating. The present disclosure stores and verifies image information using an image obtaining apparatus.
摘要:
Provided is near-field optical probe including: a cantilever arm support portion that is formed of a lower silicon layer of a silicon-on-insulator (SOI) substrate, the cantilever arm support portion having a through hole formed therein at a side of the lower silicon layer; and a cantilever arm forming of a junction oxidation layer pattern and an upper silicon layer pattern on the SOI substrate that are supported on an upper surface of the lower silicon layer and each have a smaller hole than the through hole, a silicon oxidation layer pattern having a tip including an aperture at a vertical end, corresponding with the hole on the upper silicon layer pattern, and an optical transmission prevention layer that is formed on the silicon oxidation layer pattern and does not cover the aperture.
摘要:
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.
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:
In a folding-type directional speaker array module, when sound is output, the directionality of a high frequency band can be obtained through a center speaker module and the directionality of a low frequency band can be obtained through side speaker modules unfolded from both sides of the center speaker module. Accordingly, the speaker array module has excellent directionality in an entire frequency band. Furthermore, the folding-type directional speaker array module has high mobility and portability because the side speaker modules are folded and stored when the folding-type directional speaker array module is not used.
摘要:
In a piezoelectric speaker, an acoustic diaphragm is thicker than a piezoelectric thin film and is formed of a more flexible and higher elasticity material than the piezoelectric thin film, thereby greatly improving output sound pressure in a low frequency band and reducing sound distortion. Further, the piezoelectric thin film is attached to the acoustic diaphragm in an inclined structure in which the piezoelectric thin film is horizontally turned from the acoustic diaphragm, thereby preventing a standing wave from being created by structural symmetry and minimizing sound distortion.
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:
The present disclosure relates to security system and method based on sound field variation pattern. The present disclosure identifies a slow variation pattern of a acoustic transfer function occurring due to a gradual change in temperature and humidity of air according to a change in time and a change in a characteristic of an acoustic element, from a sudden sound field variation pattern within an internal space occurring due to an intrusion from an outside, activation of an air conditioning and heating device, and the like, or within a surveillance space induced by a change in an acoustic physical property. The present disclosure identifies sound field variation patterns occurring due to a change in an acoustic structure by an intrusion and a change in temperature and convection by air conditioning and heating. The present disclosure stores and verifies image information using an image obtaining apparatus.
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.