| 摘要 |
An acoustic probe comprising a piezoelectric ceramic transducer element energisable to emit ultrasonic signals in a first direction and in a second direction opposite to the first, and mountable on a sample to be tested so as to transmit thereto signals emitted in the said first direction, is further provided, according to the invention, with a rod-shaped acoustic waveguide having one end coupled to the transducer element to receive signals emitted by the transducer element in the said second direction and to transmit them along the waveguide, with lossy cladding material acoustically coupled to the surface of the waveguide at least at a part thereof remote from its one end, and with coupling means surrounding and mechanically secured and acoustically coupled to the ceramic element and the said one end of the waveguide, the coupling means having a surface adapted to be secured to the sample to be tested and to transmit thereto signals emitted by the transducer element. |
