JPS6413452A - Method for measuring sound pressure distribution of ultrasonic wave - Google Patents

Abstract

PURPOSE:To exactly measure a sound pressure distribution by previously determining the calibration curve of the sound pressure and digital image data with a standard sample having the acoustic properties analogous to the acoustic properties of an object to be measured and processing the image data of the object to be measured by the calibration curve. CONSTITUTION:The sound pressure distribution of the ultrasonic waves in a solid is measured by a photoelastic ultrasonic visualizing device 3. Ultrasonic waves are previously radiated from a probe 10 to the standard sample 1 consisting of a transparent material having the acoustic properties analogous to the acoustic properties of the object to be measured and the image data is inputted via a television camera 17 to a digital image processor 4. An averaging processing of plural sets of the data and a processing to subtract the background are, thereupon, executed, by which noises, etc., are decreased and the calibration curve of the digital image data versus the sound pressure is formed. The object to be measured is similarly set to the photoelastic ultrasonic visualizing device 3 and the image data is inputted to the digital image processor 4. The image data is converted to the sound pressure data by using the calibration curve and the sound pressure distribution is outputted on a television monitor 5. Since the calibration curve is determined, the sound pressure distribution in the solid is quantitatively measured.