Abstract: An ultrasonic wave transmitting and receiving apparatus comprises a plurality of electrical-acoustic converting elements arranged in the same plane; a clock pulse generator; a plurality of first switching circuits coupled between the clock pulse generator and each of the electrical-acoustic converting elements; a data signal receiving circuit; a plurality of second switching circuits coupled between the data signal receiving circuit and each of the electrical-acoustic converting elements; a first control circuit adapted to control the first switching circuit so as to radiate a beam of ultrasonic wave from the electrical-acoustic converring element into a to-be-measured subject by sequentially supplying the clock pulse of the clock pulse generator; and to control the second switching circuit so as to sequentially supply to the data signal receiving circuit an electric signal generated from the electrical-acoustic converring element which receives a beam of ultrasonic wave reflected from the subject; three memo

Abstract: In the illustrated embodiment the ultrasonic applicator is activated to emit ultrasonic pulses along a plurality of scan lines simultaneously, the echo signals of all simultaneously scanned lines being stored and then rapidly read out during ultrasonic scanning along a further set of lines, the individual lines of each set being displayed in sequence and the successive sets being correspondingly displaced on the image screen so as to reproduce the ultrasonic image.

Abstract: In an illustrated embodiment the line generator for the image display device is operated at a relatively high frequency such as 200 Hz while the actual ultrasonic scanning takes place at a pulse repetition rate of 50 Hz. Preferably alternately operable buffer memories store successive lines of ultrasonic echo signals, and then provide readout of the lines at a higher rate consistent with the display line frequency. In the example given, each stored echo line is read out twice in successive display line intervals. By suitable control of the readout timing, one set of staggered pairs of display lines may be displayed during one image cycle, and an interleaved set of display line pairs may be activated during alternate image cycles in conjunction with interlaced scanning operation of the ultrasonic applicator.

Abstract: An improvement to a pulse-echo ultrasonic-imaging system employing an acoustic focusing device occupying a fixed aperture to both illuminate internal structure of a visually opaque object with a scanning focused beam of ultrasonic energy and for returning a reflected signal portion of the scanning focused beam passed therethrough for detection. The improvement accomplishes real time scanning by scanning all of the image samples within a group of such samples in a time period not much longer, at most, than the round-trip travel time delay of the focused beam required to receive the reflected signal portion of only a single sample for detection. By way of example, this may be accomplished by a phased-array transducer arrangement.

Abstract: An improved pulse-echo ultrasonic-imaging system for scanning, in real time, objects such as soft tissue within a living human body. It employs a transducer including first and second parallel wave-energy generating electrodes extending linearly in a first direction and a linear array of image-spot detecting electrodes also extending in this first direction and is situated half-way between the first and second electrodes. Scanning in a second direction orthogonal to the first direction is provided by counter-rotating Risley prisms rotating at a predetermined rate. The distance between each of the first and second electrodes and the linear array is related to this predetermined rate such that reflected wave energy is always directed to the linear array.

Abstract: A B-scan ultrasonic imager produces a rectilinear image and has a linear transducer array with only one switch per element. Individual elements or overlapping transmit subarrays are selected sequentially to generate pulses of ultra-sound. Received echo signals are sequentially sent down a long shift register delay line, are tapped off at the pulse repetition rate, and delayed by different amounts in the several channels and summed to effect time delay focusing of the echoes. The video output signal is post-processed to improve the TV monitor picture; interpolated image lines are conveniently derived with this architecture.

Abstract: An ultrasonic imaging system for medical and industrial applications produces quantitative acoustic impedance distributions from reflection data. The method and scanner apparatus with analog computation circuitry herein described acquires echo pulses reflected from impedance discontinuities in the specimen and computes impedance projections. The ensemble of projections, as in other computerized tomography systems, is used for reconstruction of the images which in this case are impedance distributions in a thin slice of the specimen.

Abstract: An array of transducers is focussed by insertion of a means for providing a small variable delay between each transducer and a selected tap on a master delay line.

Abstract: N elementary transducers are distributed regularly along a line of scanni An ultrasonic frequency receiver is associated with phase lag means. The distribution over n successive elementary transducers of the phases corresponding to focusing at a predetermined distance or several successive distances from the line is stored. That distribution corresponds to several Fresnel zones. Switches first connect a generator to a group of n' transducers corresponding to the central Fresnel zone of said stored distribution and later connect a group of n transducers to the receiver direct and via the phase lag means according to the stored distribution(s). The groups of n' and n elementary transducers are shifted along the line at intervals of time. The phase lag means may consist of inverter means causing a phase angle of .pi..

Abstract: A device in which focussed ultrasonic beams are used by way of binary distribution of the phase of the signals occurring in a mosaic of transducers. The material of which the transducers are made can be polarized, which enables the prefocussing of the ultrasonic beam to be transmitted or received, and also enables point-wise scanning and scanning by double focussing according to the X-direction and the Y-direction.

Abstract: A device for ultrasonic examination, comprising a flat mosaic of a row of transmission transducers and a number of rows of receive transducers which are symmetrically arranged with respect thereto. The device furthermore comprises means for applying actuation pulses to one transmission transducer at a time, and means for enabling receive transducers in the time interval following each actuation pulse, and for at the same time displaying on an image display device an image of a section of the examined body in a plane perpendicular to the plane of the mosaic and through the line of transmission transducers.

Abstract: Moving section plane pictures of a specimen are produced by contacting a predetermined peripheral portion of an ultrasonic transducer head with the specimen in the section plane. The transducer head has a circular internal cavity in which a wheel is mounted eccentrically for rotation about an axis. A plurality of ultrasonic transducers are mounted peripherally on the wheel. The gap formed between a transducer and the internal surface of the transducer head is a minimum along the peripheral portion where contact to the specimen occurs. Each transducer is energized only when passing through the sector subtended by the peripheral portion in contact with the specimen and echoes received by the transducer are displayed on a screen whose base line is synchronized to the movement of the ultrasonic beam.

Abstract: A method and apparatus for ultrasonic nondestructive testing of workpieces include automatic compensation of echo responsive electrical signals commensurate with preprogrammed test parameters. The test parameters include at least one of the following: depth dependent correction of the individual DGS (distance, gain, size) values for each respective probe; correction for material related properties of the workpiece and coupling medium; correction for temperature affecting the testing of the workpiece. Preferably, a compensating signal generated commensurate with the sum of the correction signals is used for varying either the gain of a receiver amplifier or a predetermined level provided to a comparator circuit or both. Embodiments disclosed are applicable for processing both analog and digital echo responsive electrical signals.

Abstract: There is disclosed an ultrasonic tomography apparatus of electronic scanning type in which an array of ultrasonic transducer elements are excited with desired time delays allotted for the transducer elements thereby to transmit and receive ultrasonic beams at a deflection angle corresponding to the desired time delays, and the received echo signal of the ultrasonic beams is displayed on a CRT display device in a form of a tomograph of a sample to which the ultrasonic beams are directed. The apparatus comprises a memory in which both of first signals representative of the time delays given to the transducer elements in dependence on given deflection angles and signals designating display position in the X- and Y-directions of the CRT are previously stored and read out for producing delays allotted for the transducer elements and displaying the received echo signal on the CRT.

Abstract: A real-time ultrasonic imaging system includes a display which is compensated for the non-ideal characteristics of the search beam profile. Echo responsive electrical signals are provided to a preprogrammed computing means for being processed to compensate for the characteristics of the test probe. The processed signals are displayed as being in focus at all distances from the probe, thereby resulting in an image exhibiting improved resolution.

Abstract: Combination Doppler and B-scan ultrasonic imaging apparatus is disclosed which includes visual display means for the simultaneous visual display of received ultrasonic Doppler and B-scan information. The apparatus includes first and second focused transducers associated with the Doppler and B-scan systems, which transducers are individually mounted for movement along parallel linear paths. The transducers each comprise a generally semi-cylindrical shaped body of piezoelectric material having opposite end faces upon which electrodes are disposed for connection to Doppler and B-scan transmitter and/or receiver units. The flat side walls of the piezoelectric bodies are positioned closely adjacent a mid-plane extending between the transducers, and means are provided for focusing the transducers at substantially the same depth for operation along a common focal region at, or adjacent, the mid-plane. One such focusing means includes acoustic lenses carried by the piezoelectric bodies.

Abstract: A technique of displaying information obtained by ultrasonic echoscopic examination of an object which comprises the steps of transmitting pulses of ultrasonic energy along a plurality of beams into the object and receiving echoes of said pulses reflected along the beams by acoustic impedance discontinuities within the object, the beams being directed from a plurality of spaced positions relative to the object and along a plurality of beam directions at each position, comprises forming a first display of information representative of the position of acoustic impedance discontinuities within the object from the echoes received along the plurality of beams as a compound scan of the object, and forming a second display of information from echoes received along selected beams of the plurality of beams as a simple scan of the object.