| 摘要 |
PURPOSE:To prevent the disturbance in the sound field of the ultrasonic waves to be transmitted and to obtain excellent frequency characteristics by packing materials having a high attenuation rate into the region of an element exposed part where a matching layer is not formed, thereby radiating the uniform ultrasonic waves from all the regions of the aperture radiating the ultrasonic waves of a probe. CONSTITUTION:A layer 8 formed by mixing microballoons and cork powder which are the materials having the high attenuation rate of frequencies is packed onto the earth part, i.e., a conductor 7. The ultrasonic wave radiated from the region of the earth electrode of a piezoelectric element 2 are attenuated by the layers 8 and the ultrasonic waves are no longer radiated to the outside or are extremely weak, even when radiated. No influence is thus exerted at all on the transmission and reception characteristics of this probe. |
