| 摘要 |
An ultrasonic imaging device includes a transducer assembly for transmitting ultrasound pulses into a portion of a structure to be imaged and receiving ultrasound scattered by said structure portion and generating signals in response thereto, means to energize said transducer assembly to transmit said pulses, scanning means for progressively relating said transducer assembly to successive portions of said structure according to a scanning pattern, and receiver and signal processing means for assembling an image from said generated signals, the transducer assembly comprising separate transmitting and receiving transducers, one of said transducers being a simulated conical transducer having a line focus, and the other of said transducers having its axis in parallel alignment with said line focus, the scanning means being operative to move said line focus in relation to a structure to be imaged in accordance with said scanning pattern. The simulated conical transducer includes a transducer element and an associated acoustic reflector system such that an active surface of the transducer element is perceived at said line focus as a conical transducer having a surface of much larger area than said active surface and having a half angle such that rays converge on said line focus at a predetermined angle of at least 20 DEG to the latter. The transducer element may have a cylindrical active surface associated with a single conical reflector, a planar active surface associated with two conical reflectors.
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