摘要:
In an ultrasonic imaging device having an image synthesizing unit, correlation between images to be synthesized is computed for balancing between an improvement in contrast resolution and an improvement in spatial resolution, and an amount of displacement between the images is computed. When the amount of displacement is large, the signals after envelop detection are synthesized. When the amount of displacement is small, RF signals are synthesized. Alternatively, the mixing frequency may be variable according to the amount of displacement, and the balance between an improvement in spatial resolution and that in contract resolution is achieved according to a degree of the positional displacement.
摘要:
In an ultrasonic imaging device having an image synthesizing unit, correlation between images to be synthesized is computed for balancing between an improvement in contrast resolution and an improvement in spatial resolution, and an amount of displacement between the images is computed. When the amount of displacement is large, the signals after envelop detection are synthesized. When the amount of displacement is small, RF signals are synthesized. Alternatively, the mixing frequency may be variable according to the amount of displacement, and the balance between an improvement in spatial resolution and that in contract resolution is achieved according to a degree of the positional displacement.
摘要:
In an ultrasonic imaging device having an image synthesizing unit, correlation between images to be synthesized is computed for balancing between an improvement in contrast resolution and an improvement in spatial resolution, and an amount of displacement between the images is computed. When the amount of displacement is large, the signals after envelop detection are synthesized. When the amount of displacement is small, RF signals are synthesized. Alternatively, the mixing frequency may be variable according to the amount of displacement, and the balance between an improvement in spatial resolution and that in contract resolution is achieved according to a degree of the positional displacement.
摘要:
In an ultrasonic imaging device having an image synthesizing unit, correlation between images to be synthesized is computed for balancing between an improvement in contrast resolution and an improvement in spatial resolution, and an amount of displacement between the images is computed. When the amount of displacement is large, the signals after envelop detection are synthesized. When the amount of displacement is small, RF signals are synthesized. Alternatively, the mixing frequency may be variable according to the amount of displacement, and the balance between an improvement in spatial resolution and that in contract resolution is achieved according to a degree of the positional displacement.
摘要:
Means for measuring and evaluating a dynamic property of a blood flow in a superficial blood vessel of a living body are constructed.A physical stimulus is given to the blood flow, and an ultrasonic response from the blood flow to the physical stimulus is measured and evaluated, which allows the blood property to be evaluated noninvasively and dynamically. Therefore, a medical check and a lifestyle-related diseases prevention effect are promising.
摘要:
The present invention realizes a Doppler velocity detecting technique capable of performing velocity detection and analysis with a suppressed error while excellently distinguishing a clutter signal, and provides an ultrasonographic device using the technique. In a Doppler velocity detection device comprising means for transmitting/receiving pulse waves to/from a subject a plurality of times, and velocity analyzing means for analyzing a velocity of a moving reflector in the subject on the basis of a reception echo signal, the velocity analyzing means obtains a complex expansion coefficient by linearly connecting an expansion coefficient of an even-numbered degree term and an expansion coefficient of an odd-numbered degree term which is different from the even-numbered degree term by one degree, derived when reception echo time-series signals obtained by arranging reception echo signals of equal lapse time from pulse transmission times in order of the transmission times are expanded as components of a Legendre polynomial starting from the 0th degree, by using an imaginary unit as a coefficient, and obtains a signed velocity signal of a moving reflector in the subject on the basis of-the ratio between the magnitude of each complex expansion coefficient and the magnitude of an interval between the complex expansion coefficients.
摘要:
A transducer for transmitting and receiving ultrasonic waves to a diaphragm-based ultrasonic transducer device using silicon as a base material. An electro-acoustic transducer device which can have a first electrode formed on top of, or inside, a substrate and having a thin film provided on top of the substrate. The device can also have a second electrode formed on top of, or inside, the thin film. A void layer can be provided between the first electrode and the second electrode. A charge-storage layer can be provided between the first electrode and the second electrode. A source electrode and a drain electrode can also be provided for measuring a quantity of electricity stored in the charge-storage layer.
摘要:
This invention provides an ultrasonic imaging system that implements imaging by distinguishing sharply and definitely the echo components generated by scattering in a microbubble contrast medium, from the tissue harmonic components generated by nonlinear propagation of a transmitted pulse. This ultrasonic imaging system, constructed to transmit/receive ultrasonic pulses to/from a living body and form a contrast image of the inside of the living body by using the contrast-imaging microbubbles, repeats the transmitting/receiving operations four times in all, under the same transmitting/receiving focus conditions at different phase angles [(a)=0°, (b)=120°, (c)=−120°, (d)=180°] of the carrier of a transmitted pulse wave including a common envelope signal, sums up three time-series receive echo signals associated with (a), (b), (c), forms the contrast image, sums up two time-series receive echo signals associated with (a), (d), forms an image of the living body having a nonlinear pulse propagation property, and makes a superimposed display of the two kinds of images.
摘要:
To provide an ultrasonograph capable of generating a transmission beam comprising a main beam having a uniform width over a wide range in an ultrasonic wave propagation direction by one-time transmission of an ultrasonic pulse. A weighted mean value of a plurality of transmission delay time values corresponding to focal lengths of transmission pulse waves having a plurality of focal points which are set in the ultrasonic wave propagation direction is calculated for each of elements constituting a transmission aperture and used as the delay time. Waves are actually transmitted with the weighted mean value as delay time. As the weight used for obtaining the delay time mean value, first, a transmission effective aperture width according to each transmission focal length is selected, and a weight in the direction of the transmit aperture realizing the width is calculated and is used in a focal length direction. As a result, the curvature of a wave front of a wave transmitted is close to that of the wave front of a short focal length in the center portion of the transmit aperture, and is close to that of the wave front of a long focal length in the peripheral portion. Consequently, a non-cylindrical wave front is formed. Thus, a transmission beam including a relatively narrow main beam with a uniform width over a wide range in the ultrasonic wave propagation direction can be generated by one-time transmission of an ultrasonic pulse.
摘要:
In a semiconductor diaphragm type electro-acoustic transducer device having no necessity for a DC bias voltage applied as a result of a charge-stored layer being provide between electrodes, electro-mechanical conversion efficiency undergoes a change owing to time-dependent change in a quantity of stored electricity due to leakage of charge, and so forth. As for sensitivity of signal reception, provided by an ultrasonic array-transducer made up of the electro-acoustic transducer devices each as a basic unit, not only a main beam sensitivity undergoes drift as a result of drift in the electromechanical conversion efficiency, but also there result deterioration in an acoustic S/N ratio, and deterioration in directionality of an ultrasonic beam. In order to resolve those problems, there is provided an electro-acoustic transducer device comprising a first electrode formed on top of, or inside a substrate, a thin film using silicon or a silicon compound as a base material thereof, provided on top of the substrate, a second electrode formed on top of, or inside the thin film, a void layer provided between the first electrode and the second electrode, a charge-stored layer for storing charge given by the first electrode and the second electrode, provided between the first electrode and the second electrode, and a source electrode and a drain electrode, for measuring a quantity of electricity stored in the charge-storage layer.