APODIZATION TECHNIQUES FOR TRANSDUCER ARRAYS (18-Jan-2010)

RP13284

BRIEF ABSTRACT

    The present invention discloses a technique for apodization to a transducer array such as, ultrasound transducers. The technique described herein utilizes pre-existing interconnect circuitry to perform the apodization as an additional function for systems that lack apodization capability.

KEYWORDS

    Apodization, transducer array, ultrasound transducer(s), interconnect circuitry, parasitic capacitance, parasitic loading and resistive loading

DETAILED DESCRIPTION

    In recent years, ultrasonic imaging techniques have become prevalent in clinical medical diagnosis. This technique has been used to measure and record the dimensions and position of deep lying organs and physiological structures throughout the body. A wide variety of ultrasound transducers and systems are used for imaging purposes. The systems range from a single element mechanically swept scanner, to linear arrays, to phased array sector scanners.

    Typically, various parallel piezoelectric transducer elements are arranged as parallel columns along the lateral direction of the transducer to form a phased array transducer. Further, this is supplemented with beam forming and steering control in the lateral direction.

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APODIZATION TECHNIQUES FOR TRANSDUCER ARRAYS

RP13284

    Apodization is one technique that is commonly performed by an ultrasound system in order to improve image quality through reduction of side lobes. The reduction of side lobes increases image contrast, which may in turn, improve the ability to detect certain targets. The apodization is usually performed within the ultrasound system, by the main beam former or by a processing chip.

    However, for systems in which apodization capability is not built in, such as low-cost or highly portable miniature systems, other methods are required for increasing the image contrast and to detect specific targets. Conventionally, there exists no technique for improving the image contrast without the built in capability of apodization. However, such a technique is attractive for its potential significant cost benefits and highly useful for portable systems. Therefore, there is a need in the state of art for developing a technique that provides increased image contrast even without any built in capability of apodization in a system.

    The present technique proposes the use of pre-existing interconnect circuitry for performing the apodization to a transducer array, i.e. ultrasound transducer array. Figure 1 illustrates an ultrasound system that comprises a system, an interconnect and a transducer. The apodization is achieved by designing the interconnect circuitry in such a way that the array elements are intentionally subject to differential parasitic loading consistent with a desired apodization pattern across the transducer array.

    In one aspect, the parasitic loading is a capacitiv...