| 摘要 |
PURPOSE:To obtain an image sharp over the entire part of an image plane by transmitting a ultrasonic wave while automatically changing the focusing position with respect to the specimen. CONSTITUTION:The respective piezoelectric trasducers of an ultrasonic vibrator 10 are connected to the predetermined delay lines of a delay circuit 30 via a tap changeover circuit 20. The tap change-over control information of said circuit 20 is beforehand stored in a memory device 40 so that suitable delay amounts are given according to the ultrasonic waves of different kinds of focal lengths and frequencies in the respective scanning lines. The predetermined storage contents are successively selected with the signal from a control unit 60 by a selection circuit 50, and changing-over is accomplished according to the contents thereof. The excitation signal is applied via the delay circuit 30 to the ultrasonic vibrator 10. The received signal is applied to a display control circuit 120 via a receiving gate circuit 90, a filter circuit 100 and a signal processing circuit 110, to display on a display device 130. |
