title: Semicylindrical acoustic transducer from a dielectric elastomer film with compliant electrodes.
abstract: A semicylindrical acoustic transducer was constructed using a dielectric elastomer film with compliant electrodes that is an electroactive polymer composed of a polyurethane elastomer base and polyethylene dioxythiophene/polystyrene sulfonate electrodes. The use of this dielectric elastomer is advantageous because polyurethane is a common material that keeps its shape without any rigid frame. Because the dielectric elastomer films are essentially incompressible, electric-field-induced thickness changes are usually translated into much larger changes of the film area and side length. Here it is proposed that this change in side length can be utilized for sound generation when the film is bent into a semicylindrical shape. Accordingly, a semicylindrical acoustic transducer was fabricated using a film of thickness of 300 μm and its acoustic characteristics were investigated. The transducer can be operated at low applied voltages by reducing the film thickness, as long as the film is thick enough to generate sufficient force to overcome sound radiation impedance. The second harmonic distortion of the transducer was also investigated as a function of the ratio of the direct current bias voltage to the alternating current audio signal amplitude.
authors: NHK Science & Technology Research Laboratories, Setagaya-ku, Tokyo, Japan. sugimoto.t-fg@nhk.or.jp
authors: Takehiro
authors: T
authors: Sugimoto
authors: Kazuho
authors: K
authors: Ono
authors: Akio
authors: A
authors: Ando
authors: Yuichi
authors: Y
authors: Morita
authors: Kosuke
authors: K
authors: Hosoda
authors: Daisaku
authors: D
authors: Ishii
mesh_terms: D000162:Acoustics / Q000295:instrumentation*; D019086:Bridged Bicyclo Compounds, Heterocyclic; D003187:Compliance; D020724:Elastomers; D004553:Electric Conductivity; D004566:Electrodes; D004867:Equipment Design; D008962:Models, Theoretical; D009038:Motion; D011108:Polymers; D011137:Polystyrenes; D011140:Polyurethanes; D013016:Sound; D014159:Transducers; D014732:Vibration
chemical_list: D019086:Bridged Bicyclo Compounds, Heterocyclic; D020724:Elastomers; D011108:Polymers; D011137:Polystyrenes; D011140:Polyurethanes; C121383:poly(3,4-ethylene dioxythiophene); C003321:polystyrene sulfonic acid