Ultrasound imaging beam-former apparatus and method

Abstract

In some illustrative embodiments, an incoming signal from a transducer in an ultrasound imaging beam-former apparatus is applied to an in-phase sample-and-hold and a quadrature sample-and-hold. The quadrature sample-and-hold may be clocked a quarter period behind the in-phase sample-and-hold. The output of the sample-and-holds are applied to in-phase and quadrature analog-to-digital converters. A magnitude calculator receives the in-phase and quadrature digital values, and outputs a magnitude. A phase calculator receives the in-phase and quadrature digital values, and outputs a phase. An apodizer applies a difference between an amplitude of the outgoing signal and the magnitude and applies a first illumination to a image point in substantial proportion to the difference, and a phase rotator applies a second illumination to the image point in substantial proportion to the phase.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS [0001] The present application is National Stage filing under 35 U.S.C. 371 of International Applications No. PCT / US2004 / 000887 which claims priority to U.S. Provisional Application Ser. Nos. 60 / 440,020 filed on Jan. 14, 2003, 60 / 439,990 filed on Jan. 14, 2003, and 60 / 440,262 filed on Jan. 15, 2003 the entire disclosures of which are incorporated herein by reference.BACKGROUND [0002] 1. Field of the Invention [0003] The present invention relates to ultrasonic diagnostic imaging systems and methods. More specifically, the preferred embodiments relate to a device and method for ultrasound imaging beam-forming that may be incorporated in a substantially integrated hand-held ultrasonic diagnostic imaging instrument. [0004] 2. Introduction [0005] Medical imaging is a field dominated by high cost systems that may be so complex as to require specialized technicians for operation and the services of experienced medical doctors and nurses for image int...

AI Technical Summary

Problems solved by technology

Medical imaging is a field dominated by high cost systems that may be so complex as to require specialized technicians for operation and the services of experienced medical doctors and nurses for image interpretation.

However it makes ultrasound impractical for many of the routine tasks for which it would be clinically useful.

While far less expensive than high-end systems, these systems are still very sophisticated and require a well-trained operator.

Furthermore, at this price few new applications may be opened.

Commercial ultrasound systems have been limited to one-dimensional (1-D) or linear transducer arrays until fairly recently.

Providing separate multiplex and receive circuitry is manageable with this many transducers, albeit with significant use of expensive high-voltage switches.

Maintaining separate receive, transmit, and multiplex partitioning for the transducers in such an array creates a tremendous burden in terms of cost, space, and complexity.

The power consumption and heat dissipation of thousands high-voltage multiplexers is enough to discourage the use of two-dimensional arrays in portable ultrasound imaging systems.

Implementation of time delays requires sufficient memory to hold a few hundred samples per channel to implement an adequate delay envelope, constraining system complexity.

Time delay beam-forming requires significant fast memory to implement a reasonable delay envelope.

Using a demodulation based approach to generate I / Q data may necessitate significant extra circuitry on each channel, while use of the Hilbert transform may require a significant amount of memory to hold the raw RF data.

Accordingly, existing ultrasound systems with thousands of separate transmit and receive switches may be too expensive for many applications.

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