Ultrasonic probe device and its control method

摘要

An ultrasonic probe device includes capacitive micromachined ultrasonic transducers, a band control unit and a bias voltage change unit. Each of the transducers belongs to one of groups, each of the groups includes at least one of the transducers. The band control unit determines the bias voltage value which varies for each of the groups, and a timing to apply the direct-current bias voltage having the bias voltage value so that all frequencies included in an operating frequency are transmitted and/or received by the ultrasonic probe device during an operation period. The bias voltage change unit changes the direct-current bias voltage to be applied to the capacitive micromachined ultrasonic transducers in accordance with the bias voltage value and the timing.

主权项

1. An ultrasonic probe device comprising:
a plurality of ultrasonic transducers, wherein each of the plurality of ultrasonic transducers is configured to transmit and/or receive ultrasonic waves in a frequency range that varies with a bias voltage value of a bias voltage applied to the each of the plurality of ultrasonic transducers; and a band control unit configured to perform a determination function to determine the bias voltage value of the bias voltage applied to the each of the plurality of ultrasonic transducers during an operation period of the plurality of ultrasonic transducers such that a predetermined continuous frequency band is covered by a combination of the frequency ranges of the transmitted and/or received ultrasonic waves from the plurality of ultrasonic transducers, wherein the determination function comprises determining:
a first bias voltage value of a first bias voltage to be applied to a first ultrasonic transducer of the plurality of ultrasonic transducers such that the first ultrasonic transducer transmits and/or receives ultrasonic waves in a first frequency range, anda second bias voltage value of a second bias voltage to be applied to a second ultrasonic transducer of the plurality of ultrasonic transducers such that the second ultrasonic transducer transmits and/or receives ultrasonic waves in a second frequency range, at least a part of the second frequency range being different from the first frequency range.