| 摘要 |
PURPOSE:To suppress a lowering of resolving power without reducing the number of receiving vibrators even in their end part scanning and to obtain an image of a wide visual field width by deflecting the receiving directionality of an ultrasonic wave when the signal of the arrangement end part of the vibrators to be obtained. CONSTITUTION:When an end part image is obtained, control performing dynamic focusing while receiving directionality is turned to the outside is performed by a transmission system 2, a vibrator selection switch 11 and a digital receiving system 10. When receiving directionality is turned to the outside, control reducing the angle of deflection thereof with the depth of a covering point is also performed in the same way. The scanning direction of the (n-1)-th transducer is divided into fine sections in the same way as the scanning direction of the n-th transducer and 1-N is used from the vibrators 1-(N-M+1) of an array type probe to converge the beam to the fine sections. The same operation is repeated up to the n/2-th scanning and, in the (n/2+1)-th scanning, vibrators from 1-2 to 1-(M+1) are used to allow the centers of (M) vibrators to coincide with a scanning position. |
