Patent 5740128 Issued on April 14, 1998. Estimated Expiration Date: May 3, 2016. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
A method for imaging a target including a nonlinear contrast agent includes the steps of transmitting ultrasonic energy at a fundamental frequency and receiving reflected ultrasonic energy at a harmonic of the fundamental frequency. The ultrasonic energy is transmitted in power bursts, each having a respective envelope shape, wherein the envelope shapes rise gradually to a respective maximum value and fall gradually from the respective maximum value. Ultrasonic energy in the transmit beam is focused in an elongated high power region, as for example by means of a line focus.
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