Abstract: A composition providing a two-part adhesive consists of an acrylate monomer and perester catalyst, comprising the polymerizable part, and a ferric ion-accelerated butyraldehyde/aniline activator comprising the other.

Abstract: A system for dispensing a radiation-curable adhesive substance employs a shutter for controlling the period of irradiation. A hand-held assembly, remote from the control unit of the system, permits convenient placement and curing of the adhesive deposit utilizing, respectively, a syringe for the containment of the substance and a light guide for transmitting the actinic radiation to the work site.

Abstract: An improved ultrasound transceiver providing enhanced imaging by selective filtering of the received signal to provide a variable frequency, constant bandwidth filtering of the received echo signals. The transceiver provides a constant bandwidth filtering by upconverting the received signals to a higher incremented frequency, which is thereafter detected. The resulting signals are then displayed wherein the number of false multiple images is reduced, and the signal quality from the deeper tissue discontinuities is enhanced. The resulting signal is thereafter post-processed to provide enhanced information which is used to display structural features.

Abstract: An ultrasound transceiver providing enhanced imaging by selective filtering of the received signal to provide a variable frequency, constant bandwidth filtering of the received echo signals. The resulting signals are then detected to produce a signal, which when displayed, has a reduced number of false multiple images and enhanced signal quality from the deeper tissue discontinuities. Additionally, the received signal is detected in quadrature by reference to a simulated carrier pilot tone having a nonconstant frequency relationship to the transmitted signal. The resulting signal is post-processed to provide information which is used to display structural features, and in addition, the velocity profile of blood flow. The structure and velocity image information is superimposed to provide a composite signal wherein the static and dynamic characteristic of a patient is completely reported to the observer.

Abstract: An ultrasound imaging probe suitable for concentric on-axis biopsy procedures. The probe according to the present invention includes an aperture through which a biopsy needle is inserted to sample a target tissue previously located by the ultrasound probe. In operation, the ultrasonic probe is first positioned on the subject over a target tissue. A cursor is moved to visually overlap the target tissue within the subject, and the depth is indicated on a corresponding display. A biopsy needle is selected and adjusted to extend to the indicated depth when inserted through the ultrasonic probe and transducer aperture into the subject. Thus the apparatus according to the present invention provides for the improved biopsy procedures through the use of a probe having a needle entranced through the source aperture, used for imaging, thus minimizing risk and error arising from conventional off-axis needle entrances.

Abstract: An ultrasound tranceiver providing enhanced imaging by selective filtering of the received signal to provide a variable frequency, constant bandwidth filtering of the received echo signals. The resulting signals are then detected to produce a signal, which when displayed, has a reduced number of false multiple images and enhanced signal quality from the deeper tissue discontinuities. Additionally, the received signal is detected in quadrature by reference to a simulated carrier pilot tone having a nonconstant frequency relationship to the transmitted signal. The resulting signal is post-processed to provide information which is used to display structural features, and in addition, the velocity profile of blood flow. The structure and velocity image information is superimposed to provide a composite signal wherein the static and dynamic characteristic of a patient is completely reported to the observer.

Abstract: An ultrasound probe includes an acoustical mirror that deflects an ultrasound beam generated by an ultrasound crystal toward an object under examination. The probe includes a thin flat motor whose rotor is controlled by a control system. The control system creates commutating signals that are applied to stator coils of the motor. An error signal that is related to the difference between the actual and desired positions of the object rotated by the motor is applied to the commutating signals to alter their amplitude or polarity to change the torque developed by the motor.

Abstract: A real-time ultrasonic transducer for use in a scanning system and a novel drive circuit therefor are provided. The transducer includes a housing and a transducer assembly mounted therein for movement in a predetermined manner. An electromagnet causes the transducer assembly to move in such a predetermined manner. The drive circuit reverses the polarity of the voltage applied to the electromagnet when the transducer assembly reaches a predetermined limit of movement thereby reversing the direction of movement thereof. The drive circuit and the transducer assembly are located within the transducer housing. The drive circuit includes a set-reset (R-S) flip-flop that reverses the polarity of the voltage applied to the electromagnet. The two conventional collector resistors of the flip-flop are each replaced by a transistor circuit thereby providing the R-S flip-flop with power amplification capability.

Abstract: The present invention provides an ultrasonic scanning transducer for use in an ultrasonic scanning system that examines an object by directing a series of ultrasonic waves into the object, receiving electrical signals related to the echoes generated by the ultrasonic waves when they strike acoustical interfaces within the object, and displaying the information borne by the electrical signals relating to the nature and location of acoustical interfaces within the object. The ultrasonic scanning transducer includes transducer elements secured to a permanent magnet mounted for rotational movement within the housing of the transducer and a stator assembly for rotating the transducers and magnet continuously in a single direction. The stator assembly receives a periodic signal having a zero average value and creates therefrom a unidirectionally rotating magnetic field which exerts a force on and rotates the permanent magnet.