Ultrasonic diagnostic device and ultrasonic probe
A plurality of transmission and reception circuits are connected to a plurality of vibration elements. The transmission and reception circuit includes a basic delay circuit and a fine delay circuit. The basic delay circuit delays a transmission signal and a reception signal for sub beamforming. The fine delay circuit is configured to be capable of performing delay finer than that of the basic delay circuit. A quantized delay error is compensated for by the fine delay circuit at the time of transmission.
1. An ultrasonic diagnostic device comprising:
a vibration element array which is provided within an ultrasonic probe and is constituted by a plurality of vibration elements arrayed two-dimensionally;
an element circuit array which is provided within the ultrasonic probe, is constituted by a plurality of element circuits connected to the plurality of vibration elements, and has a sub beamforming function; and
a control circuit that applies matrix control, which is a combination of row unit delay control and column unit delay control, to the element circuit array, wherein
each of the plurality of element circuits includes:
a basic delay circuit which delays a transmission signal; and
a fine delay circuit which is configured to be capable of performing delay finer than that of the basic delay circuit and delays an output of the transmission signal from the basic delay circuit;
the basic delay circuit operates in accordance with a basic clock; and
the fine delay circuit operates in accordance with a plurality of clocks having different phases and generated from the basic clock, wherein
a row control signal for compensating for a first quantized delay error occurring through the row unit delay control and a column control signal for compensating for a second quantized delay error occurring through the column unit delay control are given to each of the plurality of element circuits, and
the fine delay circuit delays the transmission signal in accordance with the row control signal and the column control signal, to thereby compensate for the first quantized delay error and the second quantized delay error.
2. The ultrasonic diagnostic device according to claim 1 , wherein
the fine delay circuit includes:
a delay device column to which the output from the basic delay circuit is input and which is constituted by a plurality of delay devices connected to each other in series; and
a selection device which selects any one candidate signal, from among a plurality of candidate signals output from the delay device column and delayed in a stepwise manner, as the transmission signal subjected to fine delay in accordance with the row control signal and the column control signal.
3. The ultrasonic diagnostic device according to claim 1 ,
wherein
the row control signal includes a first row control signal for compensating for a third quantized delay error occurring through the row unit delay control and a second row control signal for compensating for the first quantized delay error occurring through the row unit delay control
the column control signal includes a first column control signal for compensating for a fourth quantized delay error occurring through the column unit delay control and a second column control signal for compensating for the second quantized delay error occurring through the column unit delay control,
a basic delay controller which corrects a first delay amount of the basic delay circuit in accordance with the first row control signal and the first column control signal is provided, and
a fine delay controller which selects a second delay amount of the fine delay circuit in accordance with the second row control signal and the second column control signal is provided.
4. The ultrasonic diagnostic device according to claim 1 , further comprising:
a transmission main beamformer; and
a transmission sub beamformer group which is provided between the transmission main beamformer and the vibration element array, wherein
the element circuit array constitutes the transmission sub beamformer group.
5. The ultrasonic diagnostic device according to claim 1 , further comprising:
a transmission main beamformer; and
a plurality of transmission sub beamformers groups which are provided in a stepwise manner between the transmission main beamformer and the vibration element array, wherein
the element circuit array constitutes a first transmission sub beamformer group, among the plurality of transmission sub beamformers groups, that is closest to the vibration element array.
6. The ultrasonic diagnostic device according to claim 1 , wherein
the basic delay circuit is for transmission and reception, and
the fine delay circuit is for the transmission.
7. An ultrasonic probe comprising:
a vibration element array which is constituted by a plurality of vibration elements;
an element circuit array which is constituted by a plurality of element circuits connected to the plurality of vibration elements; and
a control circuit that applies matrix control, which is a combination of row unit delay control and column unit delay control, to the element circuit array, wherein
each of the plurality of element circuits includes
a basic delay circuit which delays a transmission signal, and
a fine delay circuit which is configured to be capable of performing delay finer than that of the basic delay circuit and delays an output of the transmission signal from the basic delay circuit;
the basic delay circuit operates in accordance with a basic clock; and
the fine delay circuit operates in accordance with a plurality of clocks having different phases and generated from the basic clock, wherein
a row control signal for compensating for a first quantized delay error occurring through the row unit delay control and a column control signal for compensating for a second quantized delay error occurring through the column unit delay control are given to each of the plurality of element circuits, and
the fine delay circuit delays the transmission signal in accordance with the row control signal and the column control signal, to thereby compensate for the first quantized delay error and the second quantized delay error.