Matsushita Electric Industrial Co., Ltd.

Ikuo Sakai

Masami Kawabuchi

Yasuhiro Nakamura

Nobuaki Furuya

Koetsu Saito

Hideyuki Tanaka

Yasuhiko Nakayama

Hiroyasu Karimoto

Pulses of an ultrasonic wave beam are emitted into a body at a predetermined repetition period. Echo pulses of the ultrasonic wave beam are received via a pulrality of different channels. Each of the received pulses is converted into corresponding electric signals of the respective channels. A pair of adders invert signs of alternate ones of pairs of the electric signals of adjacent channels, summing the inverted sign electric signals with remaining non-inverted sign electric signals, converting the electric signals into a pair of complex signals having phases which are spatially different from each other by 90 degrees. An autocorrelation function of the complex signals is calculated. A component of a speed of moving matter within the body in a predetermined direction is calculated on the basis of the autocorrelation function. The moving matter causes the echo pulses. The predetermined direction is perpendicular to a direction of travel of the ultrasonic wave beam pulses.

Ultrasonic diagnostic apparatus

An ultrasonic Doppler blood flow velocity detection apparatus comprises: a signal producing circuit for producing trigger pulses, a sampling clock signal having a given phase relation with the trigger pulses, and a pair of quadrature signals of a given frequency in response to the trigger pulses. A transducer transmits also receives ultrasonic waves in response to the trigger pulses; The transducer also receives ultrasonic waves reflected back by an ultrasonic-wave reflective object and converts the received ultrasonic waves into an electric echo signal. A Doppler shift detection circuit, responsive to the pair of quadrature signals and the echo signal, detects the Doppler shift. An averaging circuit, responsive to the sampling clock, and the Doppler shift; averages plural time-different values of the Doppler shift, thereby producing a signal indicative of flow velocity of the ultrasonic-wave reflective object. The detection apparatus may further comprise a weighting circuit responsive to the output of the Doppler detection circuit and the sampling clock signal for weighting every value of the plural time-different values.

Ultrasonic doppler blood flow velocity detection apparatus

An ultrasonic Doppler blood flow detection apparatus of the invention comprises: a transducing circuit for emitting ultrasonic waves at a predetermined interval and for receiving reflected ultrasonic waves from an object in the blood vessel and converting the received signal into an electric echo signal; a frequency-difference signal producing circuit for producing frequency-difference components between the echo signal and first pair of quadrature signals of a frequency f1 in response to the echo signal and the first pair of quadrature signals; first and second Doppler signal detection circuit for detecting first and second Doppler signals of upper and lower sidebands of the frequency f1 from the frequency-difference components in response to second pair of quadrature signals of a frequency f2; and a frequency difference calculation circuit for calculating frequency difference between output signals from the first and second Doppler signal detection circuits. The frequency difference indicates compressed Doppler shift frequency which can detect a higher velocity of blood flow.

Ultrasonic Doppler blood flow velocity detection apparatus

An ultrasonic blood velocity detector comprises an ultrasonic probe emitting ultrasonic wave into an examined body and converting echoes of the emitted ultrasonic wave into an echo signal. The echo signal is processed into a detection signal through phase detection. A first Doppler signal and a second Doppler signal are derived from the detection signal. The first Doppler signal represents a flow of blood. The second Doppler signal mainly contains clutter components. A difference in phase between the first and second Doppler signals is calculated.

Ultrasonic blood velocity detector

Pulses of an ultrasonic wave beam are emitted into a body at a predetermined repetition period. Echo pulses of the ultrasonic wave beam are received via a plurality of different channels. Each of the received pulses is converted simultaneously into corresponding electric signals of the respective channels. A time-dependent change in a variation between the electric signals of the respective channels is derived. A component of a speed of moving matter within the body in a predetermined direction is calculated on the basis of the derived time-dependent change. The moving matter causes the echo pulses. The predetermined direction is perpendicular to a direction of travel of the ultrasonic wave beam pulses.

An ultrasonic Doppler blood flow velocity detection apparatus comprises: a pulse generation circuit for generating pulses at a predetermined interval; a transducer for transmitting ultrasonic waves in response to each of the pulses and for receiving reflected ultrasonic waves from a reflective object in the blood of a human body and converting the received ultrasonic waves into an electric echo signal; an extraction circuit for extracting signal components of first and second frequencies f1 and f2; a signal producing circuit for producing a signal having a frequency of .vertline.f1-f2.vertline. using output signals of the extraction circuit; a detection circuit for detecting amplitude of an output signal of the frequency difference signal producing circuit circuit and for phase-comparing the output signal with a reference signal; and a reference signal generation circuit for generating the reference signal of a predetermined frequency fr in response to each of the pulses, the predetermined frequency fr being approximately equal to the frequency difference .vertline.f1-f2.vertline.. The invention also discloses a method for detecting blood flow velocity.

Ultrasonic doppler blood flow velocity detection apparatus and a method

An ultrasonic probe includes a first group of one or more piezoelectric elements extending concentrically, and a second group of one or more piezoelectric elements extending concentrically and extending outward of the elements in the first group. The elements in the first and second groups form a front surface via which ultrasonic wave is transmitted and received. The elements in the first and second groups are separated by predetermined gaps. Areas of the respective elements in the second group over the front surface are substantially equal to each other within an accuracy corresponding to areas of the gaps over the front surfaces. Areas of the respective elements in the first group over the front surface are substantially equal to half the areas of the respective elements in the second group within an accuracy corresponding to the areas of the gaps.

Ultrasonic probe

An ultrasonic wave diagnostic apparatus having an array of electro-acoustic transducer elements and respective channels for supplying drive signals to the electro-acoustic transducer elements and amplifying received echo signals from these elements, with the respective overall gains of the channels being controlled by corresponding values of weighting data. A set of mutually independent D/A converters, smaller in number than the number of electro-acoustic transducer elements, produce weighting data for respective ones of the channels that are spaced apart by a fixed number of channels. Respective interpolated values of weighting data for the remaining channels are derived by analog operations executed upon each of successive pairs of D/A converter outputs.

Ultrasonic wave diagnostic apparatus employing interpolated values of

A magnetic amorphous alloy having a compositional formula

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Kawasaki, Japan

Ikuo Sakai