| 摘要 |
PURPOSE:To provide an ultrasonic diagnostic device with a high sensitivity by furnishing it with a vibrator consisting of a laminate of piezo elements made from solid solution type single-crystals of zinc-lead niobate-lead titanate. CONSTITUTION:Electrodes 2, 3 are formed on the surfaces of the first piezo element 1, and to the one 3, a second piezo element 4 is affixed, and leads 5 are drawn out of the electrodes 2, 3. A drive signal is impressed between these leads 5, and it is possible to transmit and receive ultrasonic signals in two frequency bands. The frequency ratio can further be widened by forming piezo element from solid solution type single-crystals of zinc-lead niobate-lead titanate having an electromechanical bond factor k'33 of 83% approximately. The ultrasonic probe equipped with a vibrator consisting of a laminate of such piezo elements 1, 4 made of single-crystals of solid solution type has a wider frequency band width on the high-frequency side than any conventional probe. This method further enhances the S/N of Doppler information, increases the depth of the view field of a CT image, and extending the region of diagnosis. |
