| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To equalize frequency response to low frequencies in the shorter axis direction of an ultrasonic probe. <P>SOLUTION: In the ultrasonic diagnostic system, a piezoelectric layer 2 includes: a piezoelectric layer 2-3 (first piezoelectric layer) of which one surface is an ultrasonic wave-outputting surface; a piezoelectric layer 2-4 (second piezoelectric layer) laminated on the other surface of the ultrasonic wave-outputting surface of the first piezoelectric layer; a common electrode 8 provided on a lamination boundary surface between the first piezoelectric layer and the second piezoelectric layer to which ultrasonic signals are supplied; a first ground electrode 7-1 provided on the ultrasonic wave-outputting surface of the first piezoelectric layer; and a second ground electrode 7-2 provided on a backside on the other side of the lamination boundary surface of the second piezoelectric layer. The first piezoelectric layer and the second piezoelectric layer are respectively formed in specified thickness. On the backside of the electrode in contact with the second piezoelectric layer, a regulation layer 9 is provided which comprises material having sound impedance similar to that of piezoelectric material composing the piezoelectric layer. The regulation layer is formed in such a way that its thickness in the shorter axis direction perpendicular to the arrangement direction of an ultrasonic vibrator gets gradually thicker from a center toward the end. <P>COPYRIGHT: (C)2009,JPO&INPIT</p> |
