| 摘要 |
PROBLEM TO BE SOLVED: To provide an ultrasonograph outputting easy-to-listen doppler sound by which spatial spread can naturally be felt. SOLUTION: The ultrasonograph has a direction separating circuit (10) for separating a positive frequency component P(t) and a negative frequency component N(t) of doppler signals I(t), Q(t) output from an orthogonal detecting circuit (3), a first filter (11) for attenuating a lower area to a higher area of the positive frequency component P(t), a second filter (12) for attenuating a higher area to a lower area of the positive frequency component P(t), a third filter (13) for attenuating a higher area to a lower area of the negative frequency component N(t), a fourth filter (14) for attenuating a lower area to a higher area of the negative frequency component N(t), an adder (15L) for adding the outputs of the first filter (11) and the third filter (13), and an adder (15R) for adding the outputs of the second filter (12) and the fourth filter (14). The right and left sound amount ratio is changed according to the frequency; thereby a sound source position is felt to be spread and can be naturally and easily listened in the ultrasonograph. COPYRIGHT: (C)2011,JPO&INPIT |
