Abstract:
An electromechanical transducer according to an embodiment of the present invention is capable of selectively performing a transmitting and receiving operation by using elements of different shapes. The electromechanical transducer has a plurality of cells, each of which has a vibrating film including two electrodes provided with a gap therebetween, two driving and detecting units, a potential difference setter, and a switch. Each of the driving and detecting units implements a transmitting and/or a receiving function. A first or second element includes first or second electrodes which are electrically connected and further connected to the common first or second driving and detecting unit, respectively. The potential difference setter sets a predetermined potential difference between the reference potentials of the first and second driving and detecting units, respectively, and the switch switches between the first and second driving and detecting units to perform the transmitting and receiving operation.
Abstract:
Various embodiments of an ultrasound probe for use with an ultrasound system are provided to enable local waveform generation with respect to the ultrasound probe. The ultrasound probe includes a plurality of transducer elements which are independently configured to transmit distinct waveforms. Certain embodiments include a variety of probes that house one or more waveform generators on application specific integrated circuits (ASICs).
Abstract:
For the purpose of reducing the load on hardware for driving a two-dimensional array ultrasonic probe having a multiplicity of transducers, an ultrasonic diagnostic apparatus includes programmable gain amplifiers a00-a99 for amplifying signal voltages e00-e99 from transducers in a two-dimensional array ultrasonic probe, voltage-to-current converters h00-h99 for converting the voltages into current signals i00-i99, a matrix switch M for outputting additive current signals I0-I9 obtained by dividing the current signals i00-i99 into groups and adding current signals in respective groups, current-to-voltage converters H0-H9 for converting the currents into voltage signals, programmable gain amplifiers A0-A9, A-D converters C0-C9, and a digital beamformer unit B for conducting reception beamforming using digital signals D0-D9 and outputting an acoustic line signal W.
Abstract:
An ultrasonic diagnostic apparatus is capable of displaying a three-dimensional image by performing three-dimensional scanning in an object with ultrasonic beams at rapid speed. Small transducer blocks are formed through selective connection on a two-dimensional transducer array of an ultrasonic probe. Driving pulse signals are modulated and these driving pulse signals, each having respectively different frequencies, are simultaneously provided to the selected small transducer blocks, causing said small transducer blocks to transmit ultrasonic beams to the interior of the object. Waves reflected from the interior of the object are received by each small transducer block. After the echo signals received by each small transducer block are demodulated, these signals are input to a phasing circuit to generate a plurality of received beam signals. The selected position of the small transducer blocks is moved at each repetition of ultrasonic transmission/repetition. The received beam signals are then image-processed image data, and thus displayed on a display.
Abstract:
A portable electronic device (100) includes a vibrating transducer having a resilient support and a first mass supported by the first resilient support forming a mechanical resonator, and an electrical circuit coupled to the first vibrating transducer to apply a drive signal. A plurality of tactile vibration transducers (130, 140) can work in unison to produce strong tactile stimulus (216, 228, 230).
Abstract:
For the purpose of reducing the load on hardware for driving a two-dimensional array ultrasonic probe having a multiplicity of transducers, the present invention comprises programmable gain amplifiers a00-a99 for amplifying signal voltages e00-e99 from transducers in a two-dimensional array ultrasonic probe, voltage-to-current converters h00-h99 for converting the voltages into current signals i00-i99, a matrix switch M for outputting additive current signals I0-I9 obtained by dividing the current signals i00-i99 into groups and adding current signals in respective groups, current-to-voltage converters H0-H9 for converting the currents into voltage signals, programmable gain amplifiers A0-A9, A-D converters C0-C9, and a digital beamformer unit B for conducting reception beamforming using digital signals D0-D9 and outputting an acoustic line signal W.
Abstract:
A mechanical resonator has an electronically adjustable resonance frequency and is especially adapted to be used as a tunable vibration absorber. The mechanical resonator includes an inertial mass mounted on a free end of a spring, which is secured at its other end to the structure that is to be vibrationally damped. In order to vary the resonant frequency of the resonator, an electromechanical converter such as a piezoelectric element is connected to the spring and/or the inertial mass, and a displacement and/or acceleration sensor provides a sensor signal that is dependent on the respective displacement and/or acceleration of the spring and/or the inertial mass. An electronic control circuit generates an actuating signal based on the sensor signal. The actuating signal is applied to the electro-mechanical converter, which responsively exerts an adjusting force onto the spring and/or the inertial mass. The control circuit may include one or more variable amplifiers, inverters, and phase shifters, to control the actuating signal such that the adjusting force exerted by the electromechanical converter either counteracts or reinforces the bending force exerted by the inertial mass on the spring. In this manner, the effective total spring constant of the resonator can be increased or decreased relative to the inherent spring constant of the spring, whereby the resonant frequency is adjusted.
Abstract:
A method for compensating for inoperative transducer elements in an ultrasound transducer. The transmit voltage of the driving signals applied to transducer elements that are adjacent an inoperative element is increased to compensate for the inoperative element. Preferably, a linear interpolation used whereby the power/gain of the signals to be applied to the inoperative element is divided equally among the adjacent operative elements. If an inoperative transducer element is adjacent more than one inoperative element, then the gain of the operative transducer element is increased accordingly for each such inoperative element. In addition, the gain of the echo signals produced by the adjacent transducer elements is increased to compete for the inoperative element.
Abstract:
An ultrasonic transducer array, and a method for manufacturing it, having a plurality of transducer elements aligned along an array axis in an imaging plane. Each transducer element includes a piezoelectric layer and one or more acoustic matching layers. The piezoelectric layer has a concave front surface overlayed by a front electrode and a rear surface overlayed by a rear electrode. The shape of each transducer element is selected such that it is mechanically focused into the imaging plane. A backing support holds the plurality of transducer elements in a predetermined relationship along the array axis such that each element is mechanically focused in the imaging plane.
Abstract:
A circuit for causing an element to produce a substantially linear response to an input signal comprising an element for providing a response, a transistor oscillator circuit for providing an electrical output signal of variable amplitude to excite the element in response to the input signal, the transistor oscillator circuit normally causing the electrical output signal to vary non-linearly with respect to the input signal, and microprocessor means for correcting the non-linear relationship between the input signal and the electrical output signal to thereby cause the electrical output signal to vary substantially linearly with respect to the input signal when the input signal is applied to the microprocessor means.