Abstract:
A transducer (102) comprising a longitudinal bar of piezoelectric material (200) having one longitudinal face substantially covered with a first electrode (202) and the opposite longitudinal face in contact with a predetermined plural number of separate electrodes (204-1, 204-2, ... 204-n) spaced along the length thereof, permits all detected echoes to be processed by a single low input impedance amplifier (206) permanently coupled to the first electrode.
Abstract:
A lens assembly (100) is comprised of a physical acoustic lens (106) having a fixed relatively short focal length serially spaced from an electronic acoustic lens (114) having any selected one of a plurality of different relatively long focal lengths. Such a lens assembly is suitable for use in a pulse-echo ultrasonic-imaging system for imaging a deep structure (102).
Abstract:
Transducer (100) completely immersed in ultrasonic propagating liquid (102) can be oscillated back and forth at a high rate, without producing significant turbulence in liquid, if oscillation velocity varies as a predetermined smooth continuous function of time.
Abstract:
Virtual image readout of relatively high intensity is obtained by employing two readout beams, one following the path of the reference beam and the other following the path of the object beam, and modulating at least one of the beams. Amplitude, intensity or phase modulation may be employed.
Abstract:
Transducer (100) completely immersed in ultrasonic propagating liquid (102) can be oscillated back and forth at a high rate, without producing significant turbulence in liquid, if oscillation velocity varies as a predetermined smooth continuous function of time.