Handheld ultrasound imager
Described are ultrasound transducer modules and handheld ultrasound imagers including thermal and acoustic management features to produce high quality ultrasound images in a portable, handheld form factor.
1. A handheld ultrasound imager comprising:
a) a case;
b) an ultrasound transducer module disposed within the case and comprising an array of capacitive Micromachined Ultrasound Transducers (cMUTs) or piezoelectric Micromachined Ultrasound Transducers (pMUTs);
c) a first heatsink in contact with the ultrasound transducer module and associated with a first heat zone;
d) a plurality of receiver subsystems and transmitter subsystems disposed within the case and integrated into a multilayer stack;
e) a second heatsink in contact with the multilayer stack and associated with a second heat zone, wherein the second heatsink is coupled to the case, the multilayer stack, and first heatsink so as to serve as a primary structure providing an internal rigid structure for the handheld ultrasound imager;
f) an anisotropic thermally conductive material configured to move heat from the first heat zone to the second heat zone, wherein the anisotropic thermally conductive material reduces thermal coupling between the first heatsink and the second heat sink; and
g) logic to actively monitor an ultrasound procedure to manage ultrasound transducer module heating within transient heating limits by adjusting available user power to limit overheating.
2. The handheld ultrasound imager of claim 1 , wherein the anisotropic thermally conductive material comprises one or more heat pipes.
3. The handheld ultrasound imager of claim 1 , wherein the anisotropic thermally conductive material comprises one or more pyrolytic graphite sheets (PGSs).
4. The handheld ultrasound imager of claim 1 , wherein the handheld ultrasound imager is configured to generate one or more of a 2D, 3D, 4D, Doppler image with a power consumption under 11 W peak and under 7 W average.
5. The handheld ultrasound imager of claim 1 , wherein the first heatsink comprises a phase change material.
6. The handheld ultrasound imager of claim 5 , wherein the phase change material comprises paraffin, a metal matrix, or a combination thereof.
7. The handheld ultrasound imager of claim 1 , wherein the case is a multimaterial case comprising a high thermal conductivity material and a low thermal conductivity material, wherein the multimaterial case facilitates heat transfer from the first heat zone to the second heat zone.
8. The handheld ultrasound imager of claim 1 , further comprising a bezel configured to secure the ultrasound transducer module disposed within the case.
9. The handheld ultrasound imager of claim 8 , further comprising a bezel seal structure comprising spring structure to provide uniform force.
10. The handheld ultrasound imager of claim 1 , further comprising a compliant joint between the ultrasound transducer module and case to absorb force and improve drop resistance.
11. The handheld ultrasound imager of claim 1 , wherein the multilayer stack provides structural support to improve drop resistance.
12. The handheld ultrasound imager of claim 1 , wherein the case provides battery replacement access through a nondestructive case cut window which can be resealed with ultrasonic welding after battery replacement.
13. The handheld ultrasound imager of claim 1 , wherein an internal surface of the case comprises thermal insulation material that selectively insulates internal heat sources from an external surface of the case at user grip points.
14. The handheld ultrasound imager of claim 1 , wherein an interior surface of the case comprises thin film metalized shielding providing EMI shielding of electronics disposed within the case.
15. The handheld ultrasound imager of claim 1 , wherein an exterior surface of the case comprises a hydrophobic material.
16. The handheld ultrasound imager of claim 1 , further comprising a removable operator handle.
17. The handheld ultrasound imager of claim 16 , wherein the operator handle is customized to fit the hand of an individual operator.
18. The handheld ultrasound imager of claim 1 , wherein the second heatsink comprises a phase change material.
19. The handheld ultrasound imager of claim 18 , wherein the phase change material comprises paraffin, a metal matrix, or a combination thereof.