| 摘要 |
PURPOSE:To use a piezoelectric body itself as a probe and to increase an ultrasonic wave frequency by providing the piezoelectric body with plural electrodes and connecting them alternately, applying a voltage and canceling lateral oscillations between adjacent electrodes, and increasing thickness-directional oscillations of the piezoelectric body. CONSTITUTION:The ceramic piezoelectric body 3 is provided with plural electrodes 4, which are connected alternately through lead lines 1 and 2. When the voltage is applied to the lead lines 1 and 2, lateral oscillations occur between adjacent electrodes as shown by an arrow A1 and cancel each other, but thickness-directional ocsillations are high as shown by an arrow A2. An ultrasonic wave is transmitted from an electrode 6 provided to the piezoelectric body 5 to a lens 7 and focused as shown by dotted line. Then, the applied voltage is increased to increase the ultrasonic wave frequency up to about 400MHz. Thus, the piezoelectric body itself is used as the ultrasonic probe, the need for packing is eliminated, and the frequency is increased, so the probe is reduced in size and used suitably for diagnosis for insertion into the body. |
