Catheter with acoustic lens arrangement for localized ultrasonic wave transmission

A catheter comprising:

• a tube;
• at least one transmission unit disposed at a distal end of the tube and comprising a first ultrasonic sensor, the transmission unit being configured to transmit ultrasonic waves;
• at least one reception unit disposed at the distal end of the tube and comprising a second ultrasonic sensor, the reception unit being configured to receive reflected waves of ultrasonic waves transmitted from the transmission unit;
• and
• at least one acoustic lens disposed so as to cover only the transmission unit among the transmission unit and the reception unit,
• wherein:
• each of the first ultrasonic sensor and the second ultrasonic sensor includes an oscillator configured to both transmit and receive ultrasonic waves,
• the acoustic lens is movable relative to the transmission unit and the reception unit, in a manner of selectively covering only a portion of all the oscillators,
• the tube includes a first tube and a second tube that rotate relative to each other,
• the acoustic lens rotates integrally with the first tube, and
• the transmission unit and the reception unit rotate integrally with the second tube.