Ultrasonic diagnostic imaging with enhanced zoom

摘要

The ultrasonic diagnostic imaging system includes a scan-head containing a transducer array (42) which scans an image sector (10) and receives echoes from the area of the sector. The echo signals are filtered by a band-pass filter (62), and detected (64) to produce base-band echo signals. The echo signals are low-pass filtered by a variable low-pass filter (70) and stored in memory (80), and converted by a scan converter (90) into required format for display (100). A portion of an ultrasonic image can be selected for enlarged display as a "zoom" image. When the image portion is displayed in its enlarged format, the bandwidth of a filter in the ultrasonic information path is extended to increase the information content of the image portion when displayed in its enlarged format. The bandwidth is continuously optimized to maximize information content in consideration of the characteristics of the display while preventing the generation of scintillation artifacts caused by attempts to display information of an excessive bandwidth.