| 摘要 |
PROBLEM TO BE SOLVED: To perform the three-dimensional sector scanning in a small number of delay circuits even with a probe having two-dimensionally arrayed vibrators. SOLUTION: Plural ring vibrators are selected in a concentric circle for the two-dimensionally arrayed vibrators 20, and elements constituting one ring vibrator are connected to a delay circuit so that the same delay time is given to each element. The pattern of selecting the ring vibrators 20 in a concentric circle, including the position of the center, is changed according to the position of the transmission focal point and the direction of the received beam. The direction dynamic focus for slanting the received beam toward the vibrator surface moves the ring vibrators continuously according to the position of the receiving focal point. |
