248 New Patents

4676250 4677853

METHOD AND APPARATUS FOR ESTIMATING THE

ATTENUATION-VS-FREQUENCY SLOPE OF A PROPAGATION

MEDIUM FROM THE COMPLEX ENVELOPE OF A SIGNAL

Casper W Barnes assigned to North American Philips Corporation

An ultrasound attenuation scanner measures the local attenuation of tissues from pulse echo A- line data. An adaptive filter with a transfer func- tion which is the inverse of the tissue undergoing examination operates on the complex envelope of the RF signal.

4676251

IMPROVED METHOD AND DEVICE FOR MEASURING FREQUENCY DEPENDENT

PARAMETERS OF OBJECTS BY MEANS OF ULTRASOUND

ECHOGRAPHY

Jean-Luc Bernatets, Paris, France assigned to U S Philips Corporation

ULTRASONIC PROBE

Masami Kawabuchi, Yokohama, Japan as- signed to Matsushita Electric Industrial Co Ltd

An ultrasonic probe for use in an ultrasonic dia- gnosis device is disclosed. The ultrasonic probe of this invention comprises an oscillator unit having: a first rotatable composite oscillator which includes oscillators having inherent center frequencies different from each other, the oscil- lators being disposed back-to-back; and a second rotatable, frame-shaped composite oscil- lator which is disposed around the first com- posite oscillator and includes oscillators having inherent center frequencies different from each other, the oscillators being disposed back-to- back. The rotating shafts of the first and second composite oscillators are disposed concentrically in such a manner as to be freely brought into and out of mutual engagement. The oscillator unit is disposed together with an acoustic propagation liquid within an acoustic window, and circuitry for driving and controlling the respective oscil- lators or the oscillator unit are disposed within the box of the ultrasonic probe.

4677981

DEVICE FOR THE EXAMINATION OF OBJECTS BY ULTRASONIC

ECHOGRAPHY WITH ANGULAR FOCUSING

A device for the scanning of media by means of ultrasound echography, comprising at least one ultrasonic transducer (10) which is associated with a transmitter stage (50) and with a receiver- stage which comprises a conventional first pro- cessing circuit (101, 102, 103) and a second processing circuit which is connected parallel thereto and which comprises a series connection of a circuit (210) for automatic gain control as a function of the distance of the echos, a hetero- dyne circuit (230), and n parallel channels, each of which comprises a series connection of a cir- cuit for the correction of diffraction effects, a filter ( 240a . . . 240n) for selecting a narrow fre- quency band from the pass-band of the trans- ducer, a logarithmic amplifier ( 2 5 0 a . . . 250n) and a divider (260a . . . 260n) whose output is connected to one of the n inputs of a circuit (270) for determining values whose output is con- nected to the display device provided in the first processing circuit.

Roger H Coursant, Paris, France assigned to U S Philips Corporation

A device for examining objects by ultrasonic echography comprising a focusing network of n ultrasonic transducers and in which the ul- trasonic transducers (a,b,c . . . . i . . . . . n£31 1 ,n) are made of an electrostrictive material with non-remanent polarization, and the said polarization is effected by a polarization stage comprising: (1) a source ( + B 501+L ) of p polarization direct voltages, (2) a demultiplexing and branching circuit (+ B 502 + L ) receiving, on the one hand, the p polarization voltages and, in the other, combinations o f m bits selecting the said voltages in order to supply them to the transducers, (3) a circuit for the determination of a law of sensitivity (+ B 503 + L ), consisting of a counter (+ B 522 + L ) whose number of states corresponds at least to the numbers of directions to be explored and of a memory ( + B 521 + L ),