| 摘要 |
PURPOSE:To reduce the pulse repetition rate without reducing the frame rate and improve the flow speed resolving power by making a plurality of ultrasonic beams emit alternately in division in at least two different directions. CONSTITUTION:2N-pieces of ultrasonic beams are divided into two groups of A1-AN and B1-BN, and ultrasonic beams are emitted alternately in the A1 and B1 directions. The reflection echo signal is processed by a receiving transmission wave circuit 2, and introduced into a B mode tomogram signal processing system 3 and a Doppler signal processing system 4. When the reflection echo data in each beam direction are obtained, these data are inputted into a flow speed calculation circuit 22, and the average blood flow, etc., are calculated. At this time, calculation is performed in time division for the data in the A1 and B1 directions. The obtained average blood current value is sent to a DSC 7, and superposed with the B mode tomogram data in the B mode tomogram signal processing system 3, and displayed on a CRT 8. The above- described operations are repeated in total N-times in the A2 and B2 directions, and a CFM image for one screen can be obtained. |
