| 摘要 |
PROBLEM TO BE SOLVED: To provide an ultrasonograph wherein a reference signal is possible to be supplied without equipping the reference signal generating circuit exclusively for a continuous wave Doppler mode. SOLUTION: In the continuous wave Doppler mode, a transmitted signal generating circuit corresponding to a vibration elements group Tx for transmission becomes to be a generating circuit 44a used for transmission. Also, the transmitted signal generating circuit corresponding to the vibration elements group Rx for reception, which is not the generating circuit used for transmission, becomes to be the generating circuit 44b used for reception. A changeover circuit 48 outputs the transmitted signal from the generating circuit 44b used for reception to a Doppler detection member 18 directly as the first reference signal 50. A phase shifting circuit 90 carries out the 90°shifting of the phase of the first reference signal 50 and forms the second reference signal 52 which is supplied to a pair of mixer circuits 82a and 82b with the first reference signal 50. COPYRIGHT: (C)2004,JPO |
