Importance

Loading Importance Indicators...

Abstract

A method and apparatus for improving the penetration of the harmonic imaging while preserving the image uniformity by using signals from a similar frequency band to form a composite image. A near field image uses primarily tissue generated harmonic signal associated with a first transmitting event that has a center frequency of f.sub.1. Such tissue generated harmonic signal has a frequency band centered on 2f.sub.1. In the far field, fundamental echo signals from the second transmitting event that has a center frequency of f.sub.2 are primarily use. Since the center frequency f.sub.2 in the transmitting event is close to 2f.sub.1 and there is a significant overlap in frequency band between signals extracted from the first transmitting event and signals extracted from the second transmitting event, a composite image formed from these signals has similar speckle size across the whole image. The extracted signal from the second transmitting event is a fundamental component of the received echo and such signal has much larger amplitude than the tissue generated harmonic signal from the first transmitting event. Adding the fundamental signal from the second transmitting event in the far field improves the penetration of the harmonic imaging without sacrificing image uniformity.

Loading the Abstract Image...

First Claim