Diagnostic ultrasound transducer
View Patent ↗An ultrasound transducer includes an array of PZT elements mounted on a non-recessed distal surface of a backing block. Between each element and the backing block is a conductive region formed as a portion of a metallic layer sputtered onto the distal surface. Traces on a longitudinally extending circuit board—preferably, a substantially rigid printed circuit board, which may be embedded within the block—connect the conductive region, and thus the PZT element, with any conventional external ultrasound imaging system. A substantially “T” or “inverted-L” shaped electrode is thereby formed for each element, with no need for soldering. At least one longitudinally extending metallic member mounted on a respective lateral surface of the backing block forms a heat sink and a common electrical ground. A thermally and electrically conductive layer, such as of foil, transfers heat from at least one matching layer mounted on the elements to the metallic member.
1. An ultrasound imaging transducer comprising:
an array of electro-acoustic elements;
a backing block with a planar, non-recessed distal surface on which the array is mounted;
for each electro-acoustic element, an area of electrically conductive material on a corresponding portion of a contact surface of the backing block and in electrical contact with the electro-acoustic element;
a substantially rigid printed circuit board (PCB) secured to the backing block and extending in a longitudinal direction substantially perpendicular to the contact surface;
for each electro-acoustic element, at least one electrically conductive trace on the circuit board and in electrical contact with the corresponding contact surface portion and thereby with the electro-acoustic element, a solder-free electrical signal path thereby being formed through the trace to the electro-acoustic element
metallic members mounted on opposing side surfaces of the backing block, each extending in a longitudinal direction at least as far distally as a distal surface of the electro-acoustic elements and forming a common electrical ground contact and a thermal path to an external heat sink.
2. The transducer of claim 1 , in which the circuit board is embedded within the backing block.
3. The transducer of claim 1 , in which the electrically conductive material is sputtered onto the contact surface of the backing block.
4. The transducer of claim 1 , in which the PCB is mounted on a lateral surface of the backing block.
5. The transducer of claim 1 , further comprising electrically insulating elements separating the metallic members from the electrically conductive material on the contact surface of the backing block.
6. The transducer of claim 1 , wherein both metallic members are substantially perpendicular to the contact surface.
7. The transducer of claim 6 , in which each metallic member is in physical contact with lateral surfaces of the electro-acoustic elements.
8. The transducer of claim 1 , further comprising at least one acoustic matching layer mounted on a transmitting surface of the electro-acoustic element.
9. The transducer of claim 8 , in which an edge region of each metallic member is in thermal contact with a respective edge portion of the matching layer.
10. The transducer of claim 9 , further comprising a thermally conductive, metallic layer between the matching layer and the electro-acoustic element, the thermally conductive, metallic layer being in contact with the metallic members.
11. The transducer of claim 1 , in which the electro-acoustic element is made of lead zirconate titanate (PZT).
12. The transducer of claim 1 , further comprising an acoustic lens mounted longitudinally outward on the matching layer(s).
13. The transducer of claim 1 , in which the metallic members are portions of a single metallic piece extending on either side of and across a proximal surface of the backing block.