木津 克夫¹, 土屋 健神¹, 遠藤 信行¹, 名取 道也²

Katsuo KITSU¹, Takenobu TSUCHIYA¹, Nobuyuki ENDOH¹, Michiya NATORI²

¹神奈川大学工学部電気工学科, ²国立大蔵病院

¹Department of Electrical Engineering, Kanagawa University Faculty of Engineering, ²National Okura Hospital

キーワード : Acoustic field, High power ultrasonic, Hydrophone, Laser light, Refraction

In order to measure acoustic pressure in demanding clinical applications, we describe a quantitative measurement method used a laser beam that passes through the medium. When a light beam whose width is less than the length of a sound wave, it is refracted by the acoustic field, because of the gradient of the refractive index generated by sound pressure in the medium. The laser beam refracted by acoustic pressure of the transducer can be used to measure its acoustic field generated by the transducer. To confirm the validity of the method, the measured acoustic field data obtained by a PZT disk and a focus transducer were compared with those obtained from a calibrated PVDF hydrophone.