| 摘要 |
<p>A phased array acoustic imaging system including an array (0,1-127) of electromechanical transducers, a dedicated signal processing channel (60, 62) for each transducer and electronic control and delay circuits for them, transmits to and receives ultrasonic energy from a body in a controlled, steered and focused fashion. The electronic delay circuits use a unique cyclically symmetrical arrangement of identical delay cells (58), each with an electronically variable delay element (72, 74, 76) and each dedicated to a receive signal derived from at least one transducer, to form a summing delay line (56). The individual delay cells are switched under microprocessor control (54) for efficient combined linear/sector scanning or linear or sector scanning alone. The system includes means to achieve dynamic focusing (26, 46) and dynamic apodization (22, 40) in conjunction with the delay cell architecture.</p> |
