Beam former for ultrasonic diagnostic apparatus.

摘要

A beam former for a ultrasonic diagnostic apparatus is arranged to have low-bit analog-to-digital converters (4a, 5a) and enables to obtain an excellent echo signal from blood flow. The beam former further includes a sample and hold circuit (3a) for sampling an echo signal of a pulse reflected from the inside of a human body. A delaying circuit serves to delay the output of the sample and hold circuit (3a) by a delay time corresponding to an integer multiple of a transmitted pulse period and is subtracted from the output of the sample and hold circuit (3a). The subtracted output is analog-to-digital converted and is stored in a memory (7a). The memory (7a) reads out the data asynchronously with the storage. The delaying circuit is composed of an analog-to-digital converter (4a), a memory (6a) and a digital-to-analog converter (8a) and has a delay time corresponding to an integer multiple of the transmitted pulse period. <IMAGE>