| 摘要 |
<p>A real-time ultrasonic transducer (10) for use in a scanning system and a novel drive circuit therefor are provided. The transducer includes a housing (12) and a transducer assembly (64) mounted therein for movement in a predetermined manner. An electromagnet (34, 82) causes the transducer assembly (64) to move in such a predetermined manner. The drive circuit (86) reverses the polarity of the voltage applied to the electromagnet (82) when the transducer assembly (64) reaches a predetermined limit of movement thereby reversing the direction of movement thereof. The drive circuit (86) and the transducer assembly (64) are located within the transducer housing (12). The drive circuit (86) includes a set-reset (R-S) flip-flop that reverses the polarity of the voltage applied to the electromagnet (82). The two conventional collector resistors of the flip-flop are each replaced by a transistor circuit thereby providing the R-S flip-flop with power amplification capability. The ultrasonic transducer (10) can include a circuit for generating a signal related to the actual position of the transducer assembly (64). That signal is used by the scanning system to synchronize image creation with transducer assembly movement.</p> |
