| 摘要 |
<p>A method for phase and/or amplitude aberration corrections in a pulse-echo imaging system. Common mid point signals are collected and corrected for near field effect. Phase errors are measured. These errors are corrected in image forming process to improve lateral resolution in the image. Near field signal redundancy method is also used to correct amplitude aberrations caused by attenuation inhomogeneity in media and imaging system errors in a pulse-echo ultrasound imaging-system. The method includes an algorithm which measures transmission and reception phase aberration profiles separately, guaranteeing arbitrary linear term error in each profile having the same steering angle term, thus avoiding reception/transmission focuses being at different directions after correction. Also included are: simultaneous transmission methods for an array where each element uses a different frequency band or coding, and methods for aberration measurements for arrays with elements which are sensitive in a large angular range.</p> |
