Abstract: An ultrasonic focused transducer mainly used in biomedical technology, with its main frequency of 10MHz and the duration of one and a half periods, is described in detail in this paper. The following physical properties of this transducer are given: 1.The focused acoustic field recorded by an optical method; 2.The electric waveform for triggering the transducer and the related waveform received by another transducer; 3.The testing results of a sample.