| 摘要 |
PURPOSE: To obtain an ultrasonic diagnostic apparatus whose resolution is high irrespective of the distance of the depth of a display and the deflection angle of an ultrasonic beam and which can form the beam of good directivity by using two-dimensionally arranged vibrators constituting an ultrasonic probe. CONSTITUTION: Out of N×M pieces of two-dimensionally arranged vibrators constituting an ultrasonic probe 1, K×L pieces in the central part are used as vibrators 12 for both transmission and reception, the remaining vibrators in their circumference are used as vibrators 11 exclusively used for reception, a transmitting operation is performed by the vibrators 12 for both transmission and reception, and a receiving operation is performed by the vibrators 12 for both transmission and reception and by the vibrators 11 exclusively used for reception, i.e., by all the vibrators. Thereby, it is possible to obtain the ultrasonic diagnostic apparatus in which a beam width is slender and whose resolution is high. In addition, when the depth of a display is a short distance, the number of the vibrators performing the transmitting operation is reduced, and the number of the vibrators performing the transmitting operation is increased in the deflection direction when the deflection angle of an ultrasonic beam is large. |
