1020 New Patents

4870972

MULTIPLE-FREQUENCY ACOUSTIC TRANSDUCER,

ESPECIALLY FOR MEDICAL IMAGING

Charles Maerfeld, Jean F Gelly, Antibes, France assigned to Thomson-CSF

Disclosed is a probe for medical echography wherein, between the piezoelectric transducers and the backing, there is inserted a half-wave strip at the natural resonance frequency of these transducers, thus enabling the use of the probe in two distinct frequencies, one of which is substan- tially equal to half the other, and thus providing for ordinary mode B imaging and DFM Doppler imaging with one and the same probe.

4873869

DEVICE FOR THE SCANNING OF OBJECTS BY MEANS OF

ULTRASOUND ECHOGRAPHY

Mathias Fink, Meudon, France assigned to U S Philips Corporation; Fujitsu Limit

An ultrasonic echography apparatus which comprises a first processing circuit (100) of a known type for the processing of the ultrasonic ethos in order to display an A-type echogram on a display device (103), and a second processing circuit (200) which is connected parallel to the first processing circuit and which consists mainly of an amplifier (210), a group of n parallel con- nected channels (220a . . , 220n) each of which comprises at least one band-pass filter (221a . .

221n) and one envelope detector (222a . . .222n), an arithmetic circuit (240) for calculating an in- dicator for the spread of the amplitudes of the signals of central frequency of each channel, and an evaluation circuit (250) which determines, again for display on the device (103), the value of the ultrasonic attenuation factor in the tissues examined, the evaluation being possible because of the fact that the calculated spread indicator is directly locally correlated to the attenuation fac- tor which is the slope of the curve of the variation of the ultrasonic attenuation as a function of the frequency in the tissues examined.

4873984

TECHNIQUES FOR CALCULATING ULTRASONIC INTEGRATEDBACKSCATTER USING FREQUENCY OR TIME

DOMAIN TECHNIQUES

Thomas J Hunt, James G Miller, Lewis J Thomas, Hewlett E Melton, Thomas Shoup as- signed to Hewlett-Packard Company

Apparatus for deriving signals indicating a con- dition of tissue within an area by launching spaced supersonic pulses into a body under ex- amination and detecting the power of supersonic waves scattered from locations along a plurality of known paths. Gain control elements are pro- vided for compensating for changes in amplitude of the scattered supersonic waves resulting from their passage through blood or tissue, the in- creased attenuation with frequency of the spectrum of the launched pulses and the focus- sing of the launched pulses. Compensation for ring-down and the attenuation of the chest wall is also provided.